--- title: Frequently Asked Questions date: 2025-05-05T17:13:32Z modified: 2026-04-09T18:18:04Z permalink: "https://www.berkeleynucleonics.com/faq/" type: page status: publish excerpt: "" wpid: 30054 --- Pulse and Delay Generators [ a](#) #### Can Model 525 be used without a PC ? Yes, Model 525 can be powered by standard USB phone chargers and can run without the aid of a PC. A PC is only needed to set or change the pulse characteristics. [ a](#) #### Model 525 | What are the LEDs above the channel indicators (front) or under the indicators (back) for? Channel indicator illumination indicates the channel is enabled a/o pulsing. Front panel indicators are convenient if your control GUI is in a different location or you are running multiple software applications. [ a](#) #### Model 745T-20C | What if I need more than 20 channels of timing in my system? The Model 745T-20C offers 20 channels per enclosure and can be daisy chained with additional units to a single trigger. However, for complex multi-channel applications, contact the factory. We can offer a custom card-level solution which may be more cost effective. [ a](#) #### Model 765 | Are the rise and fall time the same? Yes. The Rise and Fall time for the Model 765 is 70ps. The amplitude is +/- 5V and there are 2 and 4 channel versions available. [ a](#) #### Model 765 | Can I obtain negative pulses? Yes. The Model 765 allows you to set the [pulse top](https://en.wikipedia.org/wiki/Pulse_generator) and pulse baseline from -2.5V to +2.5V. [ a](#) #### Can I use a voltage pulser to drive my laser or laser diode? You can, but there are some considerations to make. A current driver may be less problematic. See https://www.berkeleynucleonics.com/february-15th-2022-pitfalls-using-pulse-generator-drive-laser-diode for further reading. [ a](#) #### Model 577 | Can I order special outputs on just some of my channels? Yes. The Model 577 is customizable using the ‘Ordering Chart’. Select how many channels you would like for options such as high power outputs, optical isolation, impedance matching, etc. Channels are paired. [ a](#) #### What are the pitfalls of using a pulse generator to drive a laser diode? [https://www.berkeleynucleonics.com/february-15th-2022-pitfalls-using-pulse-generator-drive-laser-diode](/february-15th-2022-pitfalls-using-pulse-generator-drive-laser-diode) [ a](#) #### How do BNC digital delay generators synchronize multiple laser pulses in pump-probe experiments? In pump-probe spectroscopy and ultrafast laser experiments, BNC digital delay generators (Models 555, 575, 577) serve as the master timing hub. The DDG receives a single trigger — typically from a laser oscillator or sync output — and generates multiple independently delayed output pulses, each with picosecond-level timing resolution. These outputs trigger the pump laser, probe laser, shutter, detector gate, or camera in a defined sequence. The ability to set independent delays, widths, and polarity on each channel within a single instrument eliminates the need for multiple cascaded delay boxes, reducing jitter accumulation and simplifying the timing chain. [ a](#) #### What timing accuracy and jitter specifications should I expect from a BNC digital delay generator in a high-energy physics experiment? BNC digital delay generators deliver timing resolution as fine as 250 ps (Models 575, 577) with RMS jitter typically under 50 ps for standard configurations. For the most demanding accelerator and particle physics applications — where sub-100 ps jitter budgets are required across multiple channels — the Model 765 provides 70 ps rise time with 800 MHz bandwidth. Timing accuracy is also affected by the trigger source quality; BNC recommends using a stable, low-jitter external reference for the best system-level performance. Contact BNC’s applications team for a jitter budget analysis specific to your experiment. [ a](#) #### What is a digital delay generator and what distinguishes it from a standard pulse generator? A digital delay generator (DDG) produces precise, programmable time delays between trigger inputs and output pulses — often with picosecond-level resolution. While a standard pulse generator creates pulses with defined width and repetition rate, a DDG adds precise, independent delay control on each output channel. This is essential for synchronizing multiple instruments in laser experiments, LIDAR systems, particle accelerators, and pump-probe spectroscopy setups where timing relationships between events must be exact. [ a](#) #### How many output channels do I need in a pulse generator? Channel count depends on how many independent timing signals your experiment or system requires. Single-channel units work for simple trigger-delay applications, while multi-channel models (BNC offers up to 24 channels in the 588B) are used to synchronize cameras, lasers, shutters, detectors, and other instruments simultaneously. In multi-channel systems, outputs can typically be set with independent delays, widths, and amplitude levels per channel. Opt for a rackmount unit if channel density and stackability are priorities. Waveform Generators [ a](#) #### Model 645 | How can we provide a complex signal bit stream to the signal generator? Any user data would be downloaded from a host computer and stored in the arb memory. Any kind of zero-intersymbol-interference or spectral shaping filtering would be done mathematically on the PC before the download. [ a](#) #### Model 645 | How do I obtain FSK and BPSK modulation? Digital data from the rear panel External Trig/Gate/FSK/BPSK connector is the modulation source. [ a](#) #### Model 645 | What is the External Modulation In connector on the model 645 used for? This rear panel connector can be used to insert modulation signals onto a carrier. In conjunction with modes such as AM, FM, SSB, Ext Mod can even provide communication signals at the SIG OUT connector. [ a](#) #### Model PB-5 | What is the minimum amplitude adjustment (resolution) of the PB-5? 155 uV adjustments can be made on the key pad or spinner knob. Each “click” of the spinner makes this minimum adjustment. (Turning the spinner fast will allow it to slew millivolts or volts.) [ a](#) #### Model PB-5 | Can the NIM Pulser be operated remotely from a PC? Yes, a RS-232 port is available for this feature. Put the PB-5 in “remote” using the main menu. If the manual or PC commands are not available, type “help” and all commands will be listed. [ a](#) #### Model PB-5 | Is the “clamped mode” on the PB-5 a baseline restorer for high rate applications? No, the clamp simply preserves the amplitude of the pulse when the tail time is long compared to the desired rep rate. This feature is accomplished by clamping the pulse to the baseline before the exponential decay is completed thus allowing the next pulse to start from the baseline rather than some point on the tail. It is recommended that the delay time be set to 3 or 4 us to allow a full recovery to the base line. [ a](#) #### Model PB-5 | How do I run MCA linearity measurements? Best results are accomplished by multiple sweeps at the shortest ramp time (90 seconds). Set the number of sweeps to 999, giving a run time of just over 24 hours. For unusually demanding needs, the measurement can be repeated for several days. Since any temperature corrections are made between sweeps (not during the ramp), ramp times of 15 minutes may not give the required accuracy. Short ramps allow good random statistics for all channels as long as many sweeps are made. [ a](#) #### Model PB-5 | Why is the flat top pulse not symmetrical for minimum settings (rise time 50 ns / fall time 500 ns)? Symmetry would require a fast discharge of capacitors used to produce exponential tails. The critical issue in the PB-5 is to preserve exponential decay with a clean return to the baseline. The PB-5 meets the same fall time specification as the PB-4 with a cleaner signal as it decays to the baseline – allowing twice the rep rate (500 kHz) as the PB-4. [ a](#) #### Model PB-5 | How do I set up HyperTerminal for PB-5 remote remote operation ? Use the following settings for HyperTerminal – Baud rate: 9600, Data bits: 8, Parity: None, Stop bits: 1, Flow control: None, Emulation: VT 100 [ a](#) #### What is the difference between an arbitrary waveform generator and a function generator? A function generator produces standard periodic waveforms — sine, square, triangle, and ramp — at fixed shapes defined by the instrument. An arbitrary waveform generator (AWG) lets you define any custom waveform by uploading a point-by-point data file, making it possible to replicate real-world signals, simulate specific modulation schemes, or generate one-time transient pulses. AWGs are preferred whenever the signal shape is application-specific rather than standard. [ a](#) #### What sample rate and memory depth do I need for my AWG application? Sample rate determines the highest frequency component your waveform can accurately reproduce (you need at least 2–5x the highest signal frequency as sample rate). Memory depth determines how long a waveform can be before it repeats. For high-frequency radar or communications waveforms, models like the BNC 686 (20 GS/s, 14-bit) provide high fidelity. For lower frequency biomedical or motor control waveforms, the 645 (50 MHz) or 670C (180 MHz) are more appropriate and cost-effective. [ a](#) #### Can BNC arbitrary waveform generators output differential or balanced signals? Yes, select BNC AWG models support differential output configurations, which are important for driving differential input devices, reducing common-mode noise, and interfacing with high-speed ADCs or modulators. Contact BNC’s applications team to confirm which output topologies are available for your target model and frequency range. RF & Microwave [ a](#) #### What makes the Model 855B stand out? See this article for details – [https://www.berkeleynucleonics.com/july-5th-2022-model-855b-product-high…](/july-5th-2022-model-855b-product-highlight) [ a](#) #### RF Configuration Options | What are the differences between LN and LN+? The key difference between LN and LN+ is that LN+ will have better long-term performance—for example, a better Allan variance for a longer time. For short-time performance, they are identical. Here’s another example…Option LN adds a 100 MHz OCXO on the ref board, applying to all channels. Option LN+ will do the same. The only difference is that the OCXO will have better long-term stability. You can incorporate either LN or LN+. Options can’t be combined and priced per unit. [ a](#) #### Model 845 | Why is the front panel so small? The Model 845 is a small footprint benchtop Microwave Signal Generator with very high performance. The space saving packaging eliminates most of the front panel controls in favor of a software GUI that can be developed and enhanced over time. The low power requirements are equally resourceful, even allowing for a battery option. [ a](#) #### Model 855 | How many channels can you pack into a small enclosure? The Multi-Channel Model 855 allows for up to 4 channels in each 1U 19″ rack Mount enclosure. This design can be stacked as needed. We believe this is the most compact multi-channel offering with high performance on the market. [ a](#) #### Model 865 | Do I still need to order a Low Noise option on the 865? The Model 865 is a new product for 2018. The 1 GHz phase noise is extremely low in the standard unit (-87 dBc/Hz @ 10 Hz offset ). For even more demanding applications, we can install a special Low Noise option as in previous models. We believe the performance of the 865 with LN option is the market leading signal source in this class. (-100dBc/Hz @ 10 Hz offset) [ a](#) #### What Is Phase Noise? Phase noise is the noise produced by fast, short term fluctuations in a signal. Phase noise diminishes the signal quality and increases error rates in communication links. Although there is no such thing as “no” phase noise, the less you have, the better. [ a](#) #### Does Moore’s Law apply in Quantum Computing? This is a challenging concept. We took a look at the relationship between growth in traditional computing and quantum computing. Take a look – [January 11th 2022: Moore’s law vs quantum computing is comparing apples to oranges](/january-11th-2022-moore%E2%80%99s-law-vs-quantum-computing-it-comparing-apples-and-oranges) [ a](#) #### How do noise parameter measurements help a component manufacturer? Component manufacturers wants to bin parts (these could be transistors that are not designed for 50 ohm) based on their performance. A quick measurement of the minimum noise figure at just one frequency could allow binning parts by performance. [ a](#) #### Model 577 | Can I order special outputs on just some of my channels? Yes. The Model 577 is customizable using the ‘Ordering Chart’. Select how many channels you would like for options such as high power outputs, optical isolation, impedance matching, etc. Channels are paired. [ a](#) #### How would noise parameters help during an amplifier design? An engineer has an amplifier and wants to know whether its noise figure can be improved. The measurement of noise parameters would reveal how far away the amplifier noise figure is from the minimum possible noise figure. Noise parameters can then be used to determine what needs to be done (i.e. what “matching” network is needed) to improve the noise figure. [ a](#) #### I designed an amplifier, why do I want to measure Noise Parameters? If an engineer has developed an amplifier, he may want to know its noise figure given that an antenna is not exactly 50 ohm. The engineer measures noise parameters and then uses them to calculate the amplifier noise figure for a particular antenna. [ a](#) #### Model 7000 Series | What causes phase noise in a signal? Phase noise is the random, short term fluctuations in the phase of a waveform caused by time domain instabilities (jitter). Phase noise looks at the jitter within a single repetition. [ a](#) #### Why do I need to measure Noise Parameters when designing a receiver To design a receiver, engineers will need to select transistors for the design. You could obtain a sample of the transistor and perform noise parameter measurements while possibly setting the transistor to different power consumption settings and also varying the temperature. This gives the engineer complete information on how to select “matching” components (inductors and capacitors) that go at the input of the transistor to obtain the lowest noise figure and ultimately allows him to design the best performing receiver. [ a](#) #### Front Office | How do I order a product for fast delivery? To check price and delivery, to place a Purchase Order, or to expedite an existing order, please call 415-453-9955, email or fill out a [Get a Quote form](https://www.berkeleynucleonics.com/get-quote). Typical response time is less than 2 hours. [ a](#) #### What is a microwave signal generator and what is it used for? A microwave signal generator produces a precise RF or microwave frequency output — typically ranging from a few kHz to tens of GHz — that serves as a reference or stimulus signal in test setups. Engineers use them to characterize amplifiers, test receivers, simulate radar signals, verify satellite link budgets, and calibrate spectrum analyzers. BNC’s signal generators cover 100 kHz to 54 GHz and are widely used in defense, aerospace, quantum computing, and telecommunications R&D. [ a](#) #### What specifications matter most when choosing an RF signal generator? The most important specifications are frequency range, phase noise, output power range, and switching speed. Phase noise is especially critical for radar, communications, and quantum computing applications — lower phase noise (measured in dBc/Hz at a given offset) means a cleaner signal. For multi-channel setups, channel-to-channel isolation and phase coherence also matter. BNC offers dedicated low-noise (LN) and ultra-low-noise (LN+) options for demanding applications [ a](#) #### Can BNC signal generators be controlled remotely or integrated into automated test systems? Yes. All BNC signal generators support GPIB, USB, LAN (Ethernet), and in many cases RS-232 interfaces, and are compatible with SCPI command sets used in LabVIEW, Python, and MATLAB environments. Most models include a software GUI for PC control. For high-channel-count applications, multi-unit synchronization is available via external reference inputs (typically 10 MHz). Pulsed Power [ a](#) #### Can BNC pulse delay generators be used to drive pulsed power loads? Yes — while BNC’s pulse delay generators (such as the Model 577) are primarily designed as precision timing instruments, they are frequently used to trigger or gate high-voltage pulsed power systems. In these setups, the DDG provides the precise timing signal that initiates the pulsed power event, with the actual high-voltage switching handled by a separate driver stage. For applications requiring direct high-voltage pulsed output, BNC’s DEI division Pulsed Power product line (PVX and PCX series) is designed specifically for those loads. [ a](#) #### Can BNC’s pulsed power and delay generator products be used together in the same test system? Yes — BNC’s DEI pulsed power systems and digital delay generators are frequently integrated in the same test setups. The DDG (e.g. Model 577 or 588) provides precise timing control — triggering the pulsed power event at a defined delay and pulse width — while the DEI high-voltage unit (such as the EVO series power supply or PVX/PCX pulsers) delivers the actual high-current or high-voltage output. This combination is used in plasma research, semiconductor testing, laser diode characterization, and synchronization of multiple instruments. BNC’s applications team can assist with integration guidance. [ a](#) #### What is pulsed power and how does it differ from continuous power delivery? Pulsed power delivers high-energy electrical pulses over very short durations — typically nanoseconds to microseconds — producing instantaneous peak power levels far exceeding what continuous systems could safely sustain. This concentrated energy is used in applications like laser diode driving, plasma generation, EMC testing, pulsed electron beam systems, and high-energy physics experiments. Continuous power systems deliver steady-state current and voltage, whereas pulsed power systems store energy and release it in controlled, precisely timed bursts. [ a](#) #### What are the key safety considerations when operating high-voltage pulsed power equipment? High-voltage pulsed power systems require careful attention to electrical isolation, grounding, and discharge procedures. Key precautions include using properly rated cabling and connectors, ensuring all personnel are trained on lockout/tagout procedures, maintaining safe clearance distances, and never working alone near energized high-voltage circuits. BNC’s DEI division pulsed power equipment includes built-in safety interlocks and is designed to comply with relevant electrical safety standards. Always consult the product manual and your facility’s safety officer before installation. [ a](#) #### What types of loads can BNC pulsed power systems drive? BNC’s pulsed power product line (DEI division) is designed to drive resistive, inductive, and capacitive loads across a wide range of impedances. Common loads include laser diodes, Pockels cells, plasma chambers, solenoids, and spark gap electrodes. Models are available with bipolar output and high-current output for demanding laser diode driver applications. Specify your load impedance and required pulse parameters when requesting a quote. Radiation Detection & Isotope Identification [ a](#) #### Can the SAM 940+ detect and identify special nuclear material? Yes it can! See this article for details – [https://www.berkeleynucleonics.com/march-24th-2022-identifying-nuclear-and-special-nuclear-material-sam-940](/march-24th-2022-identifying-nuclear-and-special-nuclear-material-sam-940) [ a](#) #### How has Gamma Ray Spectroscopy evolved with respect to Isotope Identifiers? See this article – [https://www.berkeleynucleonics.com/december-23rd-2020-how-gamma-ray-spectroscopy-has-evolved](/december-23rd-2020-how-gamma-ray-spectroscopy-has-evolved) [ a](#) #### What are the similaritites between Cerium Bromide and Sodium Iodide detectors? See this article for details – [https://www.berkeleynucleonics.com/july-27th-2022-cerium-bromide-and-sodium-iodide-detectors](/july-27th-2022-cerium-bromide-and-sodium-iodide-detectors) [ a](#) #### When were neutrons discovered? See this article: [https://www.berkeleynucleonics.com/december-3th-2020-history-neutron-detection](/december-3th-2020-history-neutron-detection) [ a](#) #### Do you have a device that detects alpha, beta, gamma and x-ray radiation? The Model 907 measures alpha, beta, and gamma radiation. The device is a health and safety instrument that is optimized to detect low levels of radiation. [ a](#) #### Is your isotope identification equipment compatible with RadResponder? Our SAM III series of equipment (SAM 950, SAMpack and SAMmobile 150) is compatible with FEMA’s RadResponder network at no additional cost to the end user. [ a](#) #### Model 951 | Are there any ongoing maintenance procedures or parts need for the nukeALERT 951? No. The nukeALERT 951 recalibrates itself on power up and can be operated for many years simply by changing the battery. [ a](#) #### Model 951 | Is there any way to permanently set the sensitivity higher or lower to adjust for constant changes in background levels (around an X-Ray machine, etc)? The nukeALERT contains an Adjustment Switch that allows you to manually adjust the lowest level sensitivity of the detector. This should not be casually adjusted since it reduces the highest sensitivity of the detector. Usually, this switch is adjusted at the factory or by our tech support team. It is important to track your minimum settings so you don’t end up with 50 nukeALERT’s, each with different sensitivity settings. [ a](#) #### Model 951 | Why does the nukeALERT “recalibrate” as I travel around? When the nukeALERT is turned on, it calibrates itself to the natural radiation background. When the nukeALERT notices the background has reduced, it will recalibrate itself to improve the sensitivity. When you are traveling, your device may detect a lower natural background environment and recalibrates itself to ensure maximum detector sensitivity. You often see a reduced background count and a recalibration if you take the nukeALERT into a car or truck, for example. [ a](#) #### Model MetRad1 | How do you know if the alarm is radiation or metal? The MetRad1 has 2 different LED indicators and 2 different alarm tones to notify the operator which type of alarm is present. [ a](#) #### Model RD-150 SAMMobile | How can I determine if I need a 2x4x16 or a 4x4x16 inch NaI detector? BNC generally recommends a 2x4x16 inch detector unless greater efficiency is needed at high photon energies. For energies that include photons from U-235 and Pu-239 there is negligible difference between the two sizes. This means that the photons from both U-235 and Pu-239 are fully absorbed in either size detector. For isotopes like Cs-137 and U-238 some differences begin to show. The photon energy at 2615 keV (which is an indication of highly enriched material) is still easily detected in the 2x4x16 inch detector because the background is quite low in this region. Contact the factory for application specific support. The data for several common isotopes is shown below: ##### 2x4x16 - 100% absorption (abs) at 186 keV (includes all energies of U-235) - 87% abs at 414 keV (includes Pu-239 at 332, 375 and 414 keV) - 75% abs at 662 keV (Cs-137) - 67% abs at 1000 keV (U-238) - 52% abs at 2615 keV ##### 4x4x16 - 100% abs at 186 keV (includes all energies of U-235) - 98% abs at 414 keV (includes all energies of Pu-239) - 95% abs at 662 keV (Cs-137) - 89% abs at 1000 keV (U-238) - 76% abs at 2615 keV [ a](#) #### Model SAM 950 | What is the battery life of the SAM 950 RIID? The Model SAM 950 has a highly upgraded power source with rechargeable lithium-ion batteries. These batteries give reliable operation for over 8 hours before requiring recharge. [ a](#) #### SAM III Series | What are the advantages of smart phone technology? The smart phone technology lends itself to spectroscopy with a simplified and intuitive operation. The advantages are many fold: 1. Smart phone operation is wide spread allowing the user to quickly adapt to touch screen use and utilizing many cell phone features. 2. The device (PDA) is a quality product which gives the SAM III products reliable operation with many first-ever capabilities. The display has excellent linearity and resolution with color coded spectra and one-finger operation of the cursor. Many features are automated, for example, auto calibration and stabilization which are clearly displayed. 3. Detaching the PDA (SAM 945, RD120) allows convenient control of the instrument from a distance (bluetooth control). With the RD120 SAMpack monitoring can be clandestine with or without earphones. 4. When monitoring waste or highly active material the user can be at a safe distance (20 feet or more) and have complete control of the spectrometer which includes making measurements, taking multiple acquisitions, manipulating the spectrum, etc. Therefore, the ALARA safety practices are easily accomplished. 5. General cell phone features are incorporated into the operation of the SAM. For example, taking a picture and adding text or video describing details of the source being measured. This added information is included with the report and spectrum. [ a](#) #### SAM III Series | What is the maximum count rate for the SAM III instruments? The SAM III instruments have a maximum count rate of 100,000 CPS and 150,000 CPS depending on the amount of background and the number of energy peaks being processed. [ a](#) #### SAM III Series | What is the sigma trigger setting for? The sigma trigger allows a low threshold for sensing a radioactive source while being unaffected by false triggering due to changes in background (sigma indicates standard deviations over background). This provision automatically updates the current background which yields higher sensitivity while eliminating false triggers due to changing ambient background. This feature allows the user to survey a large area without needing to continuously stop and store a new and different background. A sigma setting of 4 is recommended. [ a](#) #### SAM III Series | What isotope libraries are supplied with the RIIDs and Backpack Systems? Berkeley Nucleonics provides the standard ANSI N42 compliant libraries for SNM, Medical, Industrial and NORM. Also a user defined library is provided. Finally, an expanded ANSI compliant library is available for CeBr and LaBr detector upgrades. New medical libraries and isotopes are updated through the product’s free apps, PeakGo and PeakAbout. [ a](#) #### SAM III Series | Why are some isotopes harder to identify at low dose rates/count rates? The example given here is for a typical background of 7 urem/hr (70 nSv/hr) which corresponds to about 250 gamma counts per second (cps). When a Ra-226 source is detected there will be an alarm at background levels but a firm ID will not occur until the cps reaches about twice the background level (500 – 600 cps for this example). This higher cps level for ID is expected since Ra-226 has many peaks and many are very low in abundance (sometimes referred to as Branching Ratio, Branching intensity or intensity of peaks.) In addition Ba-133 has similar peaks with much higher branching intensities (about 20 times higher) which add to the complexity of identifying Ra-226 especially at low cps. The library is carefully designed to take this into account but moving closer to the source or waiting a little longer for a solid ID is always important (Ba-133 ID may be seen momentarily but will cease as statistics improve). Identifying two or more isotopes each with low abundant lines (peaks) may also require moving closer to the source and possibly waiting longer to obtain good performance. U-238 is another example of a source with low abundant lines and may take up to 30 seconds or more to identify at minimum count rate (<500 cps). Users must realize that the basic specifications which are given for the Cs-137 standard is the result of a very high branching intensity (>85%) – whereas the branching intensity of U-238 lines are less than 1% of Cs-137. It is therefore expected that acquisitions on some sources will take a little longer but it is common practice to use acquisitions of at least 1 minute and to move closer to the source if possible. [ a](#) #### SAM III Series | Why is operation in the “Variable Alarm Mode” preferred and why is Auto Variable Trigger employed? When using the Variable Alarm Mode (as opposed to Fixed Alarm Mode) a low threshold can be set to start the acquisition during a search for radionuclides. A low threshold which triggers the start of an acquisition is important for achieving high sensitivity. However, changes in the background during surveillance can cause false triggers that may result in false identification of isotopes. To prevent false triggers from happening BNC uses a scheme called “Auto Variable Trigger”. This is a threshold adjustment that continuously optimizes the threshold setting automatically. Those performing environmental surveillance will find this mode especially valuable as it allows identification of NORM isotopes with the highest sensitivity possible during changes in NORM. [ a](#) #### What Types of Radiation Are There? Alpha radiation, beta radiation, gamma radiation, and x radiation. Neutron radiation is also encountered in nuclear power plants and high-altitude flight and emitted from some industrial radioactive sources. [ a](#) #### Sam 150 is good Nunc interdum lacus sit amet orci. Duis vel nibh at velit scelerisque suscipit. Pellentesque dapibus hendrerit tortor. Cras dapibus. Sed magna purus, fermentum eu, tincidunt eu, varius ut, felis. Nunc nonummy metus. Aenean posuere, tortor sed cursus feugiat, nunc augue blandit nunc, eu sollicitudin urna dolor sagittis lacus. Nam ipsum risus, rutrum vitae, vestibulum eu, molestie vel, lacus. Etiam ultricies nisi vel augue. Maecenas nec odio et ante tincidunt tempus. Donec pede justo, fringilla vel, aliquet nec, vulputate eget, arcu. Nulla facilisi. Aenean viverra rhoncus pede. Sed aliquam ultrices mauris. Etiam ut purus mattis mauris sodales aliquam. Fusce a quam. Vivamus elementum semper nisi. Nulla consequat massa quis enim. Vestibulum suscipit nulla quis orci. Fusce pharetra convallis urna. [ a](#) #### New FAQ SAM 950 Nunc interdum lacus sit amet orci. Duis vel nibh at velit scelerisque suscipit. Pellentesque dapibus hendrerit tortor. Cras dapibus. Sed magna purus, fermentum eu, tincidunt eu, varius ut, felis. Nunc nonummy metus. Aenean posuere, tortor sed cursus feugiat, nunc augue blandit nunc, eu sollicitudin urna dolor sagittis lacus. Nam ipsum risus, rutrum vitae, vestibulum eu, molestie vel, lacus. Etiam ultricies nisi vel augue. Maecenas nec odio et ante tincidunt tempus. Donec pede justo, fringilla vel, aliquet nec, vulputate eget, arcu. Nulla facilisi. Aenean viverra rhoncus pede. Sed aliquam ultrices mauris. Etiam ut purus mattis mauris sodales aliquam. Fusce a quam. Vivamus elementum semper nisi. Nulla consequat massa quis enim. Vestibulum suscipit nulla quis orci. Fusce pharetra convallis urna. [ a](#) #### Model 940 | How does SAM 940 GN neutron option work? For routine neutron confirmation, or applications where an integrated, clandestine device is required, BNC offers an Li6 solid state neutron detector internal to the gamma detector module. The benefits include a lower cost, light weight, smaller volume. This detector is available in the SAM 940-2GN and 940-3GN. The Li6 scintillator crystal (neutron detector) is embedded in the NaI scintillator crystal (gamma detector). Both scintillator crystals share the same power and amplification circuits. The MCA processes data from both materials and discriminates Neutron counts from Gamma counts. Secondary confirmation of Neutron counts can be accounted for quickly through the introduction of a tin or lead shield, or a slight retreat in the operator’s position. Contact the factory for additional training. [ a](#) #### Are there ways to increase the ruggedness of a detector for outdoor/field work? Yes – an important aspect of your product selection. See [https://www.berkeleynucleonics.com/february-23rd-2022-ruggedized-detectors-customized-scintillators-field](/february-23rd-2022-ruggedized-detectors-customized-scintillators-field) for further reading. [ a](#) #### What is the difference between SiPM and PMT readout methods? SiPMs are an alternative readout method to standard PMTs. With respect to signal processing and spectroscopic behavior, SiPMs behave differently compared to standard PMTs. The elements are typically 3×3 or 6×6 mm and can be combined into matrices. For applications where a small crystal size and low voltage operations are required SiPM readout can be a good choice. The energy resolution and noise level achievable with SiPM readouts depend on crystal dimensions, scintillation material, and how much area is covered by the SiPMs For larger scintillation crystals, it is important to strategically place as few SiPMs as possible. It is impractical to use too many SiPMs because the capacitive notice on the signal If you are interested in this readout method, please contact us [ a](#) #### What factors should I consider when customizing my scintillation detector? There is a great variety of choices to consider. Selecting the right material, geometry, readout and electronics are only a start. See [https://www.berkeleynucleonics.com/february-11th-2022-customizing-your-scintillation-detector](/february-11th-2022-customizing-your-scintillation-detector) for further reading. [ a](#) #### Does temperature affect the response of a scintillation detector? The light output (number of photons per MeV gamma) of most scintillators is a function of temperature. This is caused by the fact that in scintillation crystals, radiative transitions, responsible for the production of scintillation light, compete with nonradiative transitions (no light production). In most scintillation crystals, the light output is quenched (decreased) at higher temperatures. An example to the contrary is the fast component of BaF2 which the emission intensity is essentially temperature independent. The scintillation process usually involves three stages, production, transport and quenching centers. Competition between these three stages and all three behaving differently with temperature creates a complex temperature dependence for scintillation light output. Below is a chart with the temperature dependence of common scintillation crystals. ![](/wp-content/uploads/background_cebr3-1.png) ###### Temperature dependence of the scintillation yield of NaI(Tl), CsI(Tl), BGO and CeBr3 For most applications, the combination of the temperature dependent light output of the scintillator together with the temperature dependent amplification of the light detector should be considered. The doped scintillators NaI(Tl), CsI(Tl) and CsI(Na) show a distinct maximum in intensity whereas many undoped scintillators such as BGO show an increase in intensity with decreasing temperature. The temperature dependence of the Ce doped scintillators LBC, CeBr3 and YAP:Ce is significantly less than that of other scintillators. [ a](#) #### What wavelength is the light emission of a scintillator material? Each scintillation material has a characteristic emission spectrum, with wavelength and intensity. The shape of this emission spectrum is sometimes dependent on the type of excitation (photons/particles). ![](https://www.berkeleynucleonics.com/wp-content/uploads/wavelength_is_the_light_emission.jpg) ##### Emission spectra of NaI(Tl), CsI(Tl) and CeBr3, scaled on maximum emission intensity. Also a typical quantum efficiency curve of a bialkali photocathode and a Silicon Photomultiplier (SiPm) are shown above. This emission spectrum is of importance when choosing the optimum readout device (PMT / photodiode/SiPm) and the required window material. The graph above shows the emission spectrum of some common scintillation materials. [ a](#) #### What is Radiation Damage in Scintillators? Radiation damage is defined as the change in scintillation characteristics caused by prolonged exposure to intense radiation. This damage manifests itself by a decrease of the optical transmission of a crystal which causes a decrease in pulse height and deterioration of the energy resolution of the detector. Radiation damage other than radio-activation is usually partially reversible; i.e. the absorption bands often disappear slowly in time; some damage can be annealed thermally. In general, doped alkali halide scintillators such as NaI(Tl) and CsI(Tl) are rather susceptible to radiation damage. All known scintillation materials show more or less damage when exposing them to large radiation doses. The effects usually can only be observed clearly with thick (> 5 cm) crystals. A material is usually called radiation hard if no measurable effects occur at a dose of 10.000 Gray. Examples of radiation hard materials are CeBr3 and YAP:Ce. [ a](#) #### What is Thermal Neutron Detection? Neutrons do not produce ionization directly in scintillation crystals but can be detected through their interaction with the nuclei of a suitable element. In a 6LiI(Eu) scintillation crystal, for example, neutrons interact with 6Li nuclei to produce an alpha particle and a triton (tritium nucleus), which both produce scintillation light that can be detected. Another Li-containing scintillator is CLYC. Also enriched 6Li containing glass can be used, doped with Ce as an activator. Alternatively, Boron or Gadolinium containing inorganic scintillators can be used but these scintillators are not common. One alternative technique is to construct a large area thermal neutron detector using 6LiF/ZnS(Ag)screens. These can then be read out via green wavelength shifters by PMTs or SiPMs. [ a](#) #### What is Afterglow? To detect fast changes in transmitted intensity of X-Ray beams, such as in CT scanners or luggage X-ray detectors, crystals are required exhibiting low afterglow. Afterglow is defined as the fraction of scintillation light still present for a certain time after the X-Ray excitation stops. Afterglow originates within a millisecond and can last hours in long decay time components. Afterglow in most halide scintillation crystals can be as high as a 5-10 percent after 3 ms. The long duration afterglow in e.g. CsI(Tl) can be a problem for many applications. Afterglow in halides is believed to be intrinsic and correlated to certain lattice defects. BGO, CeBr3, and Cadmium Tungstate (CdWO4) crystals are examples of low afterglow scintillation materials. [ a](#) #### Can you explain the variety of mechanical, optical and scintillation properties of various materials? The most widely used scintillation material for gamma-ray spectroscopy is Sodium Iodide, NaI(Tl). It is hygroscopic and is only used in hermetically sealed metal containers to preserve its properties. All water-soluble scintillation materials should be packaged in such a way that they are not attacked by moisture. Some scintillation crystals may easily crack or cleave under mechanical pressure whereas others are plastic and only will deform like CsI(Tl). See our [Table of Properties](https://www.berkeleynucleonics.com/sites/default/files/products/datasheets/Scintillators%20Physical%20Properties_1.pdf) or [Table of Applications](https://www.berkeleynucleonics.com/sites/default/files/products/datasheets/Scintillators%20Common%20Applications_1.pdf) for material specific comments. [ a](#) #### What is the significance of Decay Time? Scintillation light pulses (flashes) are usually characterized by a fast increase of the intensity in time (pulse rise time) followed by an exponential decrease. The **decay time** of a scintillator is defined by the time after which the intensity of the light pulse has returned to 1/e of its maximum value. Most scintillators are characterized by more than one decay time and usually, the effective average decay time is mentioned. The decay time is of importance for fast counting and/or timing applications. [ a](#) #### What is the significance of Light Output (wavelength + intensity)? Because photoelectron statistics (or electron-hole pair statistics) play a key role in the accurate determination of the energy of the radiation, the use of scintillation materials with a high light output is preferred for all spectroscopic applications. The scintillator emission wavelength should be matched to the sensitivity of the light detection device that is used (PM, SiPm or photodiode). [ a](#) #### What is the significance of Density and atomic number (Z)? To detect y-rays efficiently, a material with a **high density and high effective Z (number of protons per atom) is required.** Inorganic scintillation crystals meet the requirements of stopping power and optical transparency. Their densities ranging from roughly 3 to 9 g/cm3 makes them very suitable to absorb penetrating radiation (γ-rays). Materials with high Z-values are used for γ-ray spectroscopy at high energies (> 1 MeV). [ a](#) #### What are the most important properties when selecting a scintillator for my application? - Density and atomic number (Z) - Light output (wavelength + intensity) - Decay time (duration of the scintillation light pulse) - Mechanical and optical properties - Cost [ a](#) #### What is a Scintillator? A scintillator is a material that exhibits scintillation, which refers to the emission of light when the material interacts with ionizing radiation. Scintillators are widely used in various fields, including radiation detection, medical imaging, and high-energy physics. Different types of scintillators exist, and some common examples include NaI (sodium iodide), LaBr (lanthanum bromide), CeBr (cerium bromide), and CsI (cesium iodide). These scintillators have distinct properties and are utilized in specific applications. Each of these scintillators has its advantages and suitability for specific applications, depending on factors such as energy resolution, light output, decay time, and cost. Researchers and engineers select the most appropriate scintillator based on the requirements of their particular application. Scintillation Detectors [ a](#) #### What are the similaritites between Cerium Bromide and Sodium Iodide detectors? See this article for details – [https://www.berkeleynucleonics.com/july-27th-2022-cerium-bromide-and-sodium-iodide-detectors](/july-27th-2022-cerium-bromide-and-sodium-iodide-detectors) [ a](#) #### When were neutrons discovered? See this article: [https://www.berkeleynucleonics.com/december-3th-2020-history-neutron-detection](/december-3th-2020-history-neutron-detection) [ a](#) #### Do you have a device that detects alpha, beta, gamma and x-ray radiation? The Model 907 measures alpha, beta, and gamma radiation. The device is a health and safety instrument that is optimized to detect low levels of radiation. [ a](#) #### What Types of Radiation Are There? Alpha radiation, beta radiation, gamma radiation, and x radiation. Neutron radiation is also encountered in nuclear power plants and high-altitude flight and emitted from some industrial radioactive sources. [ a](#) #### Are there ways to increase the ruggedness of a detector for outdoor/field work? Yes – an important aspect of your product selection. See [https://www.berkeleynucleonics.com/february-23rd-2022-ruggedized-detectors-customized-scintillators-field](/february-23rd-2022-ruggedized-detectors-customized-scintillators-field) for further reading. [ a](#) #### What is the difference between SiPM and PMT readout methods? SiPMs are an alternative readout method to standard PMTs. With respect to signal processing and spectroscopic behavior, SiPMs behave differently compared to standard PMTs. The elements are typically 3×3 or 6×6 mm and can be combined into matrices. For applications where a small crystal size and low voltage operations are required SiPM readout can be a good choice. The energy resolution and noise level achievable with SiPM readouts depend on crystal dimensions, scintillation material, and how much area is covered by the SiPMs For larger scintillation crystals, it is important to strategically place as few SiPMs as possible. It is impractical to use too many SiPMs because the capacitive notice on the signal If you are interested in this readout method, please contact us [ a](#) #### What factors should I consider when customizing my scintillation detector? There is a great variety of choices to consider. Selecting the right material, geometry, readout and electronics are only a start. See [https://www.berkeleynucleonics.com/february-11th-2022-customizing-your-scintillation-detector](/february-11th-2022-customizing-your-scintillation-detector) for further reading. [ a](#) #### Does temperature affect the response of a scintillation detector? The light output (number of photons per MeV gamma) of most scintillators is a function of temperature. This is caused by the fact that in scintillation crystals, radiative transitions, responsible for the production of scintillation light, compete with nonradiative transitions (no light production). In most scintillation crystals, the light output is quenched (decreased) at higher temperatures. An example to the contrary is the fast component of BaF2 which the emission intensity is essentially temperature independent. The scintillation process usually involves three stages, production, transport and quenching centers. Competition between these three stages and all three behaving differently with temperature creates a complex temperature dependence for scintillation light output. Below is a chart with the temperature dependence of common scintillation crystals. ![](/wp-content/uploads/background_cebr3-1.png) ###### Temperature dependence of the scintillation yield of NaI(Tl), CsI(Tl), BGO and CeBr3 For most applications, the combination of the temperature dependent light output of the scintillator together with the temperature dependent amplification of the light detector should be considered. The doped scintillators NaI(Tl), CsI(Tl) and CsI(Na) show a distinct maximum in intensity whereas many undoped scintillators such as BGO show an increase in intensity with decreasing temperature. The temperature dependence of the Ce doped scintillators LBC, CeBr3 and YAP:Ce is significantly less than that of other scintillators. [ a](#) #### What wavelength is the light emission of a scintillator material? Each scintillation material has a characteristic emission spectrum, with wavelength and intensity. The shape of this emission spectrum is sometimes dependent on the type of excitation (photons/particles). ![](https://www.berkeleynucleonics.com/wp-content/uploads/wavelength_is_the_light_emission.jpg) ##### Emission spectra of NaI(Tl), CsI(Tl) and CeBr3, scaled on maximum emission intensity. Also a typical quantum efficiency curve of a bialkali photocathode and a Silicon Photomultiplier (SiPm) are shown above. This emission spectrum is of importance when choosing the optimum readout device (PMT / photodiode/SiPm) and the required window material. The graph above shows the emission spectrum of some common scintillation materials. [ a](#) #### What is Radiation Damage in Scintillators? Radiation damage is defined as the change in scintillation characteristics caused by prolonged exposure to intense radiation. This damage manifests itself by a decrease of the optical transmission of a crystal which causes a decrease in pulse height and deterioration of the energy resolution of the detector. Radiation damage other than radio-activation is usually partially reversible; i.e. the absorption bands often disappear slowly in time; some damage can be annealed thermally. In general, doped alkali halide scintillators such as NaI(Tl) and CsI(Tl) are rather susceptible to radiation damage. All known scintillation materials show more or less damage when exposing them to large radiation doses. The effects usually can only be observed clearly with thick (> 5 cm) crystals. A material is usually called radiation hard if no measurable effects occur at a dose of 10.000 Gray. Examples of radiation hard materials are CeBr3 and YAP:Ce. [ a](#) #### What is Thermal Neutron Detection? Neutrons do not produce ionization directly in scintillation crystals but can be detected through their interaction with the nuclei of a suitable element. In a 6LiI(Eu) scintillation crystal, for example, neutrons interact with 6Li nuclei to produce an alpha particle and a triton (tritium nucleus), which both produce scintillation light that can be detected. Another Li-containing scintillator is CLYC. Also enriched 6Li containing glass can be used, doped with Ce as an activator. Alternatively, Boron or Gadolinium containing inorganic scintillators can be used but these scintillators are not common. One alternative technique is to construct a large area thermal neutron detector using 6LiF/ZnS(Ag)screens. These can then be read out via green wavelength shifters by PMTs or SiPMs. [ a](#) #### What is Afterglow? To detect fast changes in transmitted intensity of X-Ray beams, such as in CT scanners or luggage X-ray detectors, crystals are required exhibiting low afterglow. Afterglow is defined as the fraction of scintillation light still present for a certain time after the X-Ray excitation stops. Afterglow originates within a millisecond and can last hours in long decay time components. Afterglow in most halide scintillation crystals can be as high as a 5-10 percent after 3 ms. The long duration afterglow in e.g. CsI(Tl) can be a problem for many applications. Afterglow in halides is believed to be intrinsic and correlated to certain lattice defects. BGO, CeBr3, and Cadmium Tungstate (CdWO4) crystals are examples of low afterglow scintillation materials. [ a](#) #### Can you explain the variety of mechanical, optical and scintillation properties of various materials? The most widely used scintillation material for gamma-ray spectroscopy is Sodium Iodide, NaI(Tl). It is hygroscopic and is only used in hermetically sealed metal containers to preserve its properties. All water-soluble scintillation materials should be packaged in such a way that they are not attacked by moisture. Some scintillation crystals may easily crack or cleave under mechanical pressure whereas others are plastic and only will deform like CsI(Tl). See our [Table of Properties](https://www.berkeleynucleonics.com/sites/default/files/products/datasheets/Scintillators%20Physical%20Properties_1.pdf) or [Table of Applications](https://www.berkeleynucleonics.com/sites/default/files/products/datasheets/Scintillators%20Common%20Applications_1.pdf) for material specific comments. [ a](#) #### What is the significance of Decay Time? Scintillation light pulses (flashes) are usually characterized by a fast increase of the intensity in time (pulse rise time) followed by an exponential decrease. The **decay time** of a scintillator is defined by the time after which the intensity of the light pulse has returned to 1/e of its maximum value. Most scintillators are characterized by more than one decay time and usually, the effective average decay time is mentioned. The decay time is of importance for fast counting and/or timing applications. [ a](#) #### What is the significance of Light Output (wavelength + intensity)? Because photoelectron statistics (or electron-hole pair statistics) play a key role in the accurate determination of the energy of the radiation, the use of scintillation materials with a high light output is preferred for all spectroscopic applications. The scintillator emission wavelength should be matched to the sensitivity of the light detection device that is used (PM, SiPm or photodiode). [ a](#) #### What is the significance of Density and atomic number (Z)? To detect y-rays efficiently, a material with a **high density and high effective Z (number of protons per atom) is required.** Inorganic scintillation crystals meet the requirements of stopping power and optical transparency. Their densities ranging from roughly 3 to 9 g/cm3 makes them very suitable to absorb penetrating radiation (γ-rays). Materials with high Z-values are used for γ-ray spectroscopy at high energies (> 1 MeV). [ a](#) #### What are the most important properties when selecting a scintillator for my application? - Density and atomic number (Z) - Light output (wavelength + intensity) - Decay time (duration of the scintillation light pulse) - Mechanical and optical properties - Cost [ a](#) #### What is a Scintillator? A scintillator is a material that exhibits scintillation, which refers to the emission of light when the material interacts with ionizing radiation. Scintillators are widely used in various fields, including radiation detection, medical imaging, and high-energy physics. Different types of scintillators exist, and some common examples include NaI (sodium iodide), LaBr (lanthanum bromide), CeBr (cerium bromide), and CsI (cesium iodide). These scintillators have distinct properties and are utilized in specific applications. Each of these scintillators has its advantages and suitability for specific applications, depending on factors such as energy resolution, light output, decay time, and cost. Researchers and engineers select the most appropriate scintillator based on the requirements of their particular application. [ a](#) #### What is a scintillation detector and how does it work? A scintillation detector converts ionizing radiation (gamma rays, neutrons, or charged particles) into visible light pulses, which are then detected and measured by a photomultiplier tube (PMT) or silicon photomultiplier (SiPM). The material used for scintillation — such as NaI(Tl), CeBr3, or CLYC — determines the detector’s energy resolution, timing performance, and sensitivity to specific radiation types. BNC manufactures custom scintillation detectors across a wide range of crystal materials for research, defense, nuclear medicine, and environmental monitoring applications. [ a](#) #### How do I choose the right scintillation material for my application? Material selection depends on what type of radiation you’re measuring, required energy resolution, operating temperature range, count rate, and cost constraints. NaI(Tl) is the most widely used general-purpose gamma detector. CeBr3 offers superior energy resolution without requiring cooling. LaBr3 provides excellent timing and resolution but is more expensive. CLYC and CLLBC are dual-mode gamma/neutron detectors suitable for SNM detection. SrI2 delivers the highest resolution available in a room-temperature scintillator. BNC’s applications team can recommend the best material based on your specific requirements. BNC Scientific [ a](#) #### BrightSPEC | Is bGamma MCA software compatible with Macs or PCs? Yes. bGamma is a full spectroscopic package for NaI, HPGe and other spectroscopy applications. It is the only spectroscopy package that is Mac and Windows compliant. [ a](#) #### What are the pitfalls of using a pulse generator to drive a laser diode? [https://www.berkeleynucleonics.com/february-15th-2022-pitfalls-using-pulse-generator-drive-laser-diode](/february-15th-2022-pitfalls-using-pulse-generator-drive-laser-diode) Ordering Information / Contact Us [ a](#) #### Front Office | Where is the Berkeley Nucleonics headquarters? ur main headquarters is in California. Our address is 2955 Kerner Blvd, San Rafael CA 94901. We have sales offices throught the United States and in many European and Asian countries. We also have a nationwide network of approved trainers to handle product training and installation. Contact the factory at 415-453-9955 or for your closest resource. [ a](#) #### Front Office | How do I order a product for fast delivery? To check price and delivery, to place a Purchase Order, or to expedite an existing order, please call 415-453-9955, email or fill out a [Get a Quote form](https://www.berkeleynucleonics.com/get-quote). Typical response time is less than 2 hours. [ a #### Can both channels on the Model 765-HV output pulses simultaneously? ](#) Yes, both channels on the Berkeley Nucleonics Model 765-HV pulse generator are fully independent and can output pulses simultaneously. Each channel has its own pulse timing, amplitude, and width settings, so you can generate two different pulse waveforms at the same time. The channels share a common trigger input by default but can also be configured for independent triggering. This dual-channel independent operation is useful for applications requiring synchronized but different pulse outputs, such as pump-probe experiments, dual-sensor triggering, or differential pulse testing. [ a #### Can the Model 765 output 5V into a 50 Ohm load? ](#) Yes, the Berkeley Nucleonics Model 765 pulse generator is designed to deliver 5V output into a 50 Ohm termination, which is the standard impedance for most RF and high-speed test equipment. The Model 765 maintains its specified rise time and pulse fidelity when driving 50 Ohm loads. If your application requires higher voltage output into 50 Ohm — such as driving higher-threshold devices or longer cable runs — the Model 765-HV variant provides increased voltage swing while maintaining 50 Ohm drive capability. [ a #### Can the Model 765 output ±5V? ](#) Yes, the Berkeley Nucleonics Model 765 pulse generator supports output voltage swings of ±5V into high-impedance loads. The Model 765 provides adjustable output amplitude with both positive and negative voltage capability, making it suitable for applications requiring bipolar pulse outputs such as ultrasonic transducer driving, piezoelectric actuator control, and differential signal testing. For higher voltage requirements, consider the Model 765-HV variant. [ a #### Are the output channels on the Model 765 independent in multiple pulse mode? ](#) Yes, each output channel on the Berkeley Nucleonics Model 765 pulse generator operates fully independently, even in multiple pulse mode. In double pulse mode, for example, each channel has its own set of pulse parameters — pulse 1 and pulse 2 on channel 1 are completely independent of pulse 1 and pulse 2 on channel 2. This means you can configure different pulse widths, delays, and amplitudes on each output channel simultaneously. This independent channel architecture makes the Model 765 ideal for applications requiring synchronized but different pulse patterns across multiple outputs, such as multi-sensor triggering or complex timing sequences. [ a #### What is the difference between a pulse generator, current generator, delay generator, and signal generator? ](#) These four instrument types serve distinct purposes in electronic testing and measurement. A pulse generator creates precisely timed, short-duration electrical pulses used to trigger, stimulate, or test circuits and devices that respond to transient events — common in semiconductor testing, radar simulation, and laser triggering. A current generator (or current source) delivers a regulated, controllable electrical current independent of load impedance, essential for device characterization, sensor excitation, and electrochemical applications. A delay generator produces precisely timed trigger signals with programmable delays, used to synchronize multiple instruments in complex test setups — critical in time-resolved spectroscopy, particle physics, and multi-camera triggering. A signal generator creates continuous waveforms (sine, square, triangle, arbitrary) for testing amplifiers, filters, receivers, and communication systems. Berkeley Nucleonics manufactures pulse generators, delay generators (Model 577 Series), and arbitrary waveform generators (Models 670C through 686) — explore our full product line to find the right instrument for your application. [ a #### Model 577 | Can I order special outputs on just some of my channels? ](#) Yes. The Model 577 is customizable using the ‘Ordering Chart’. Select how many channels you would like for options such as high power outputs, optical isolation, impedance matching, etc. Channels are paired. [ a #### What is a digital delay generator and what distinguishes it from a standard pulse generator? ](#) A digital delay generator (DDG) produces precise, programmable time delays between trigger inputs and output pulses — often with picosecond-level resolution. While a standard pulse generator creates pulses with defined width and repetition rate, a DDG adds precise, independent delay control on each output channel. This is essential for synchronizing multiple instruments in laser experiments, LIDAR systems, particle accelerators, and pump-probe spectroscopy setups where timing relationships between events must be exact. [ a #### How many output channels do I need in a pulse generator? ](#) Channel count depends on how many independent timing signals your experiment or system requires. Single-channel units work for simple trigger-delay applications, while multi-channel models (BNC offers up to 24 channels in the 588B) are used to synchronize cameras, lasers, shutters, detectors, and other instruments simultaneously. In multi-channel systems, outputs can typically be set with independent delays, widths, and amplitude levels per channel. Opt for a rackmount unit if channel density and stackability are priorities. [ a #### Can I use a voltage pulser to drive my laser or laser diode? ](#) You can, but there are some considerations to make. A current driver may be less problematic. See https://www.berkeleynucleonics.com/february-15th-2022-pitfalls-using-pulse-generator-drive-laser-diode for further reading. [ a #### What are the pitfalls of using a pulse generator to drive a laser diode? ](#) [https://www.berkeleynucleonics.com/february-15th-2022-pitfalls-using-pulse-generator-drive-laser-diode](/february-15th-2022-pitfalls-using-pulse-generator-drive-laser-diode) [ a #### How do BNC digital delay generators synchronize multiple laser pulses in pump-probe experiments? ](#) In pump-probe spectroscopy and ultrafast laser experiments, BNC digital delay generators (Models 555, 575, 577) serve as the master timing hub. The DDG receives a single trigger — typically from a laser oscillator or sync output — and generates multiple independently delayed output pulses, each with picosecond-level timing resolution. These outputs trigger the pump laser, probe laser, shutter, detector gate, or camera in a defined sequence. The ability to set independent delays, widths, and polarity on each channel within a single instrument eliminates the need for multiple cascaded delay boxes, reducing jitter accumulation and simplifying the timing chain. [ a #### What timing accuracy and jitter specifications should I expect from a BNC digital delay generator in a high-energy physics experiment? ](#) BNC digital delay generators deliver timing resolution as fine as 250 ps (Models 575, 577) with RMS jitter typically under 50 ps for standard configurations. For the most demanding accelerator and particle physics applications — where sub-100 ps jitter budgets are required across multiple channels — the Model 765 provides 70 ps rise time with 800 MHz bandwidth. Timing accuracy is also affected by the trigger source quality; BNC recommends using a stable, low-jitter external reference for the best system-level performance. Contact BNC’s applications team for a jitter budget analysis specific to your experiment. [ a #### Model 745T-20C | What if I need more than 20 channels of timing in my system? ](#) The Model 745T-20C offers 20 channels per enclosure and can be daisy chained with additional units to a single trigger. However, for complex multi-channel applications, contact the factory. We can offer a custom card-level solution which may be more cost effective. [ a #### Model 525 | What are the LEDs above the channel indicators (front) or under the indicators (back) for? ](#) Channel indicator illumination indicates the channel is enabled a/o pulsing. Front panel indicators are convenient if your control GUI is in a different location or you are running multiple software applications. [ a #### Can Model 525 be used without a PC? ](#) Yes, Model 525 can be powered by standard USB phone chargers and can run without the aid of a PC. A PC is only needed to set or change the pulse characteristics. [ a #### Model 765 | Are the rise and fall time the same? ](#) Yes. The Rise and Fall time for the Model 765 is 70ps. The amplitude is +/- 5V and there are 2 and 4 channel versions available. [ a #### Model 765 | Can I obtain negative pulses? ](#) Yes. The Model 765 allows you to set the [pulse top](https://en.wikipedia.org/wiki/Pulse_generator) and pulse baseline from -2.5V to +2.5V. [ a #### What is the difference between an arbitrary waveform generator and a function generator? ](#) A function generator produces standard periodic waveforms — sine, square, triangle, and ramp — at fixed shapes defined by the instrument. An arbitrary waveform generator (AWG) lets you define any custom waveform by uploading a point-by-point data file, making it possible to replicate real-world signals, simulate specific modulation schemes, or generate one-time transient pulses. AWGs are preferred whenever the signal shape is application-specific rather than standard. [ a #### What sample rate and memory depth do I need for my AWG application? ](#) Sample rate determines the highest frequency component your waveform can accurately reproduce (you need at least 2–5x the highest signal frequency as sample rate). Memory depth determines how long a waveform can be before it repeats. For high-frequency radar or communications waveforms, models like the BNC 686 (20 GS/s, 14-bit) provide high fidelity. For lower frequency biomedical or motor control waveforms, the 645 (50 MHz) or 670C (180 MHz) are more appropriate and cost-effective. [ a #### Can BNC arbitrary waveform generators output differential or balanced signals? ](#) Yes, select BNC AWG models support differential output configurations, which are important for driving differential input devices, reducing common-mode noise, and interfacing with high-speed ADCs or modulators. Contact BNC’s applications team to confirm which output topologies are available for your target model and frequency range. [ a #### Model 645 | How do I obtain FSK and BPSK modulation? ](#) Digital data from the rear panel External Trig/Gate/FSK/BPSK connector is the modulation source. [ a #### Model 645 | How can we provide a complex signal bit stream to the signal generator? ](#) Any user data would be downloaded from a host computer and stored in the arb memory. Any kind of zero-intersymbol-interference or spectral shaping filtering would be done mathematically on the PC before the download. [ a #### Model 645 | What is the External Modulation In connector on the model 645 used for? ](#) This rear panel connector can be used to insert modulation signals onto a carrier. In conjunction with modes such as AM, FM, SSB, Ext Mod can even provide communication signals at the SIG OUT connector. [ a #### Model PB-5 | How do I set up HyperTerminal for PB-5 remote remote operation? ](#) Use the following settings for HyperTerminal – Baud rate: 9600, Data bits: 8, Parity: None, Stop bits: 1, Flow control: None, Emulation: VT 100 [ a #### Model PB-5 | What is the minimum amplitude adjustment (resolution) of the PB-5? ](#) 155 uV adjustments can be made on the key pad or spinner knob. Each “click” of the spinner makes this minimum adjustment. (Turning the spinner fast will allow it to slew millivolts or volts.) [ a #### Model PB-5 | Is the “clamped mode” on the PB-5 a baseline restorer for high rate applications? ](#) No, the clamp simply preserves the amplitude of the pulse when the tail time is long compared to the desired rep rate. This feature is accomplished by clamping the pulse to the baseline before the exponential decay is completed thus allowing the next pulse to start from the baseline rather than some point on the tail. It is recommended that the delay time be set to 3 or 4 us to allow a full recovery to the base line. [ a #### Model PB-5 | Why is the flat top pulse not symmetrical for minimum settings (rise time 50 ns / fall time 500 ns)? ](#) Symmetry would require a fast discharge of capacitors used to produce exponential tails. The critical issue in the PB-5 is to preserve exponential decay with a clean return to the baseline. The PB-5 meets the same fall time specification as the PB-4 with a cleaner signal as it decays to the baseline – allowing twice the rep rate (500 kHz) as the PB-4. [ a #### Model PB-5 | How do I run MCA linearity measurements? ](#) Best results are accomplished by multiple sweeps at the shortest ramp time (90 seconds). Set the number of sweeps to 999, giving a run time of just over 24 hours. For unusually demanding needs, the measurement can be repeated for several days. Since any temperature corrections are made between sweeps (not during the ramp), ramp times of 15 minutes may not give the required accuracy. Short ramps allow good random statistics for all channels as long as many sweeps are made. [ a #### Model PB-5 | Can the NIM Pulser be operated remotely from a PC? ](#) Yes, a RS-232 port is available for this feature. Put the PB-5 in “remote” using the main menu. If the manual or PC commands are not available, type “help” and all commands will be listed. [ a #### What is a microwave signal generator and what is it used for? ](#) A microwave signal generator produces a precise RF or microwave frequency output — typically ranging from a few kHz to tens of GHz — that serves as a reference or stimulus signal in test setups. Engineers use them to characterize amplifiers, test receivers, simulate radar signals, verify satellite link budgets, and calibrate spectrum analyzers. BNC’s signal generators cover 100 kHz to 54 GHz and are widely used in defense, aerospace, quantum computing, and telecommunications R&D. [ a #### What specifications matter most when choosing an RF signal generator? ](#) The most important specifications are frequency range, phase noise, output power range, and switching speed. Phase noise is especially critical for radar, communications, and quantum computing applications — lower phase noise (measured in dBc/Hz at a given offset) means a cleaner signal. For multi-channel setups, channel-to-channel isolation and phase coherence also matter. BNC offers dedicated low-noise (LN) and ultra-low-noise (LN+) options for demanding applications [ a #### What Is Phase Noise? ](#) Phase noise is the noise produced by fast, short term fluctuations in a signal. Phase noise diminishes the signal quality and increases error rates in communication links. Although there is no such thing as “no” phase noise, the less you have, the better. [ a #### Model 7000 Series | What causes phase noise in a signal? ](#) Phase noise is the random, short term fluctuations in the phase of a waveform caused by time domain instabilities (jitter). Phase noise looks at the jitter within a single repetition. [ a #### Can BNC signal generators be controlled remotely or integrated into automated test systems? ](#) Yes. All BNC signal generators support GPIB, USB, LAN (Ethernet), and in many cases RS-232 interfaces, and are compatible with SCPI command sets used in LabVIEW, Python, and MATLAB environments. Most models include a software GUI for PC control. For high-channel-count applications, multi-unit synchronization is available via external reference inputs (typically 10 MHz). [ a #### RF Configuration Options | What are the differences between LN and LN+? ](#) The key difference between LN and LN+ is that LN+ will have better long-term performance—for example, a better Allan variance for a longer time. For short-time performance, they are identical. Here’s another example…Option LN adds a 100 MHz OCXO on the ref board, applying to all channels. Option LN+ will do the same. The only difference is that the OCXO will have better long-term stability. You can incorporate either LN or LN+. Options can’t be combined and priced per unit. [ a #### Model 865 | Do I still need to order a Low Noise option on the 865? ](#) The Model 865 is a new product for 2018. The 1 GHz phase noise is extremely low in the standard unit (-87 dBc/Hz @ 10 Hz offset ). For even more demanding applications, we can install a special Low Noise option as in previous models. We believe the performance of the 865 with LN option is the market leading signal source in this class. (-100dBc/Hz @ 10 Hz offset) [ a #### Front Office | How do I get a quick quote or expedite an order? ](#) To check price and delivery, to place a Purchase Order, or to expedite an existing order, please call 415-453-9955, email or fill out a [Get a Quote form](https://www.berkeleynucleonics.com/get-quote). Typical response time is less than 2 hours. [ a #### Model 577 | Can I order special outputs on just some of my channels? ](#) Yes. The Model 577 is customizable using the ‘Ordering Chart’. Select how many channels you would like for options such as high power outputs, optical isolation, impedance matching, etc. Channels are paired. [ a #### Model 855 | How many channels can you pack into a small enclosure? ](#) The Multi-Channel Model 855 allows for up to 4 channels in each 1U 19″ rack Mount enclosure. This design can be stacked as needed. We believe this is the most compact multi-channel offering with high performance on the market. [ a #### Model 845 | Why is the front panel so small? ](#) The Model 845 is a small footprint benchtop Microwave Signal Generator with very high performance. The space saving packaging eliminates most of the front panel controls in favor of a software GUI that can be developed and enhanced over time. The low power requirements are equally resourceful, even allowing for a battery option. [ a #### What makes the Model 855B stand out? ](#) The Model 855B is BNC’s flagship multi-channel RF/microwave signal generator, offering up to 4 phase-coherent channels in a 1U rack enclosure from 300 kHz to 42 GHz. Its standout features include industry-leading phase noise, independent per-channel control, and a compact form factor. \[Full product overview →\] – [https://www.berkeleynucleonics.com/july-5th-2022-model-855b-product-high…](/july-5th-2022-model-855b-product-highlight) [ a #### Does Moore’s Law apply in Quantum Computing? ](#) Moore’s Law and quantum computing follow fundamentally different scaling paths Moore’s Law tracks transistor density, while quantum computing scales by qubit count and error rate. \[Learn more on our Quantum Computing Course →\] [https://academy.berkeleynucleonics.com/p/quantum-computing](https://academy.berkeleynucleonics.com/p/quantum-computing) [ a #### How are noise parameters used in RF component and amplifier design? ](#) Noise parameters describe a device’s noise performance versus source impedance, including key values like **Fmin** and optimal source impedance (**Zopt**), which define the lowest achievable noise. They help engineers determine how close an amplifier is to its minimum noise and guide the design of **matching networks** to improve performance, especially when the source (e.g., an antenna) is not 50 ohms. They are also used by manufacturers for **transistor binning**, allowing components to be grouped based on noise performance. [ a #### Why do I need to measure Noise Parameters when designing a receiver? ](#) To design a receiver, engineers will need to select transistors for the design. You could obtain a sample of the transistor and perform noise parameter measurements while possibly setting the transistor to different power consumption settings and also varying the temperature. This gives the engineer complete information on how to select “matching” components (inductors and capacitors) that go at the input of the transistor to obtain the lowest noise figure and ultimately allows him to design the best performing receiver. [ a #### What is the difference between the PVX-4141 and PVX-4141B? ](#) The PVX-4141 and PVX-4141B are functionally identical high-voltage pulsers with the same electrical specifications, performance characteristics, and output capabilities. The ‘B’ suffix denotes a chassis or packaging revision — not a change in electrical design or functionality. Both models are interchangeable in any application. If you are replacing an existing PVX-4141 unit, the PVX-4141B is a direct drop-in replacement with no changes needed to your setup or wiring. [ a #### Can multiple DC power supplies be combined to achieve higher voltage or current? ](#) Whether multiple DC power supplies can be combined for higher voltage or current depends on the specific model and its output topology. Some power supplies support series connection (for higher voltage) or parallel connection (for higher current), but this requires compatible output stages and proper load balancing. Not all models are designed for stacking — connecting incompatible units can damage the supplies or create unsafe conditions. Berkeley Nucleonics offers the Heinzinger EVO Series, which is adding multi-unit stacking capability. Contact our engineering team to determine the best configuration for your voltage and current requirements. [ a #### Does Berkeley Nucleonics offer service agreements for pulsed power products? ](#) Berkeley Nucleonics offers service agreements for many pulsed power products, with availability depending on the specific instrument and its value. Higher-value units such as PVX high-voltage pulsers, EVO power supplies, and PCX laser diode drivers are typically covered under multi-year service agreements that include calibration, preventive maintenance, and repair. For lower-cost accessories and modules, individual repair and calibration services are available on a per-incident basis. Contact Berkeley Nucleonics to discuss service agreement options and pricing for your specific instruments. [ a #### What is the maximum output voltage of the PCX-7500-EX? ](#) The PCX-7500-EX pulsed laser diode driver has a maximum output voltage of 110V. This higher voltage capability makes the PCX-7500-EX suitable for driving laser diode arrays and high-compliance-voltage diodes that require more voltage headroom than standard drivers provide. For applications requiring different voltage ranges, Berkeley Nucleonics offers the full PCX family of pulsed current drivers with various voltage and current configurations. Contact us with your laser diode specifications for a driver recommendation. [ a #### Which Berkeley Nucleonics laser diode driver supports 15 amp, 50 volt diodes? ](#) The Berkeley Nucleonics Model PCM-7140-200 pulsed current driver is designed to handle laser diodes requiring up to 15 amps at 50 volts. The PCM-7140-200 is part of the PCX/PCM family of pulsed laser diode drivers, which offer precise current control with nanosecond-level pulse width capability. For diodes with different current or voltage requirements, Berkeley Nucleonics offers a full range of drivers from milliamps to hundreds of amps. Contact us with your specific diode specifications for a recommendation. [ a #### Can the PVX Series be controlled with LabVIEW? ](#) The PVX Series high-voltage pulsers do not include native LabVIEW drivers, but they can be controlled indirectly through LabVIEW by automating the external power supply and pulse generator that drive them. The exception is the PVX-4000-2kV with internal high voltage, which can be interfaced directly with LabVIEW using a custom-built driver. For fully automated test setups, Berkeley Nucleonics can recommend compatible power supplies and pulse generators that include standard LabVIEW instrument drivers. [ a #### Is the PCX-7500 laser diode driver still available? ](#) The PCX-7500 pulsed laser diode driver remains available from Berkeley Nucleonics. As a specialized high-current driver, the PCX-7500 is produced in limited builds, and lead times may vary depending on component availability. Current estimated lead times are typically in the range of several months. For the most accurate delivery timeline and pricing, contact Berkeley Nucleonics directly with your quantity and delivery requirements. [ a #### What is the difference between the PVX-4140 and the PVX-4141? ](#) The PVX-4140 and PVX-4141 high-voltage pulsers are functionally equivalent, sharing the same electrical specifications and switching performance. The differences are mechanical: the PVX-4141 uses an updated chassis design. Current-production PVX-4140 units also include an updated front-panel PCB and remote signal interface that matches the newer PVX-4150/PVX-4151 design family. For practical purposes, both models are interchangeable in applications. If you are specifying a new purchase, the PVX-4141 represents the current-production chassis revision. [ a #### Do PVX high-voltage pulsers have CE or UL certification? ](#) Certification markings vary across the PVX high-voltage pulser family. The PVX-4000 series — both the PVX-4000-2kV-Int (internal power) and PVX-4000-2kV-Ext (external power) — carry CE certification. Most other PVX models, including the PVX-4110, PVX-4130, PVX-4140, and PVX-4150, do not currently carry CE, UL, or other regulatory markings. If your application requires specific certifications for compliance, contact Berkeley Nucleonics to confirm which models meet your regulatory requirements. [ a #### Do all PVX high-voltage pulsers require an external power supply? ](#) Almost all PVX Series high-voltage pulsers require an external high-voltage power supply. The single exception is the PVX-4000-2kV-Int, which has an integrated internal high-voltage source. For all other models — including the PVX-4110, PVX-4130, PVX-4140, PVX-4150, and PVX-4170 — you will need a separate DC power supply rated to the pulser’s input voltage specification. Berkeley Nucleonics offers the Heinzinger EVO Series as a matched power supply for PVX pulsers, and can recommend the right combination for your application. [ a #### Is the pulse width adjustable on Berkeley Nucleonics laser diode drivers? ](#) Yes, most Berkeley Nucleonics pulsed laser diode drivers offer adjustable pulse width, allowing you to tune the optical pulse duration to match your application requirements. The PCX Series drivers provide continuously variable pulse widths, typically ranging from nanoseconds to microseconds depending on the model. Some compact PCO Series modules have fixed pulse widths optimized for specific applications. Consult the datasheet for your specific model to confirm the pulse width range, or contact Berkeley Nucleonics to discuss which driver best matches your pulse width requirements. [ a #### What is the difference between the EVO 1500-1400 and the EVO 1500-1400 FLO? ](#) The EVO 1500-1400 and EVO 1500-1400 FLO are the same high-voltage power supply with one key difference: output grounding. The standard EVO 1500-1400 has a ground-referenced output, meaning one terminal is tied to earth ground. The FLO (floating output) version has an isolated output where neither terminal is referenced to ground. Floating output is required when your load is not ground-referenced — for example, the Berkeley Nucleonics PVX-2506 high-voltage pulser requires a floating output power supply. If you are unsure whether your application needs floating output, contact Berkeley Nucleonics engineering for guidance. [ a #### What cables and connectors are included with the PVX-4110? ](#) The PVX-4110 high-voltage pulser ships with the following cables and accessories: three high-voltage cables (part number 6050-0061) — two are used for high-voltage DC input connections and one for the pulsed output connection; and one 6-foot AC power cord (part number 1950-0002). No additional cables are required for basic operation, though you may need to provide BNC or SMA trigger cables depending on your signal source. Replacement cables and additional accessories are available separately from Berkeley Nucleonics. [ a #### Does the PVX-4130 come with a calibration certificate? ](#) The PVX-4130 high-voltage pulser ships with a checkout sheet that documents functional verification testing performed before delivery. A formal calibration certificate with traceable measurements is included with every calibration service return, and can also be requested at the time of new unit purchase at no additional charge. Berkeley Nucleonics recommends annual calibration for PVX units in active use. To request a calibration certificate with your new PVX-4130 order, include the request at the time of purchase. [ a #### Can I use one EVO Series power supply for two different voltages simultaneously? ](#) No, a single EVO Series high-voltage power supply can only deliver one output voltage at a time. Applications requiring two simultaneous voltage levels need two separate EVO units. This is because each EVO has a single regulated output stage — there is no internal switching between voltage setpoints during operation. Berkeley Nucleonics engineers can help you configure a multi-unit setup, including synchronized operation with PVX high-voltage pulsers that require dedicated power supplies. Contact us for application-specific recommendations. [ a #### Is the 24 VDC power supply included with the PVM-4210? ](#) No, the PVM-4210 does not include a 24 VDC power supply. The standard PVM-4210 shipment includes a control cable with D-Sub connector and two coaxial output cables. The external 24 VDC power supply required for operation must be purchased separately. Berkeley Nucleonics can recommend a compatible 24 VDC supply rated for the PVM-4210’s power requirements — contact us when ordering to ensure you have all necessary components for your setup. [ a #### What does a laser diode driver do? ](#) A laser diode driver is an electronic instrument that precisely controls the electrical current delivered to a laser diode, enabling stable, repeatable, and safe optical output. It regulates both current amplitude and voltage to protect the diode from overcurrent damage — even brief current spikes can permanently destroy a laser diode. Pulsed laser diode drivers, like the Berkeley Nucleonics PCX Series, add precise timing control with nanosecond-level pulse widths and adjustable repetition rates, which is essential for applications in LIDAR, time-resolved spectroscopy, medical instrumentation, rangefinding, and materials processing. [ a #### What cables are included with the Heinzinger EVO Series power supply? ](#) Each Heinzinger EVO Series high-voltage power supply ships with a high-voltage output cable featuring a male connector on one end and an unterminated end for custom connection to your load or instrument. The EVO unit itself has a female high-voltage connector. When you purchase an EVO together with a Berkeley Nucleonics PVX high-voltage pulser, the cables are pre-configured — one PVX input cable is spliced to the EVO output cable, providing a ready-to-use power connection. If you need additional or replacement cables, contact Berkeley Nucleonics for compatible cable assemblies. [ a #### Why buy a PCX-7401/7421 instead of building a custom laser diode driver? ](#) Building a custom pulsed laser diode driver requires significant electrical engineering expertise in high-speed current regulation, diode protection, and thermal management — a single design error can destroy expensive laser diodes. The Berkeley Nucleonics PCX-7401 and PCX-7421 provide professionally engineered, tested, and calibrated drivers with features that are difficult to replicate in custom builds: precision bias pulse capability for pre-conditioning the diode junction, accurately controlled low-current outputs with minimal overshoot, built-in protection circuits against overcurrent and reverse voltage, and calibrated output with documented specifications. For most applications, purchasing a proven driver is faster, safer, and more cost-effective than designing and validating a custom solution. [ a #### Does a new PVX unit include an accessory kit? ](#) Yes, every new PVX high-voltage pulser ships with a standard accessory kit included at no additional cost. The accessory kit contains the cables and connectors needed for initial setup and operation. If you need replacement parts or additional accessories, Berkeley Nucleonics also sells accessory kits separately as spare parts. Contact us for accessory kit contents specific to your PVX model. [ a #### What is pulsed power and how does it differ from continuous power delivery? ](#) Pulsed power delivers high-energy electrical pulses over very short durations — typically nanoseconds to microseconds — producing instantaneous peak power levels far exceeding what continuous systems could safely sustain. This concentrated energy is used in applications like laser diode driving, plasma generation, EMC testing, pulsed electron beam systems, and high-energy physics experiments. Continuous power systems deliver steady-state current and voltage, whereas pulsed power systems store energy and release it in controlled, precisely timed bursts. [ a #### What types of loads can BNC pulsed power systems drive? ](#) BNC’s pulsed power product line (DEI division) is designed to drive resistive, inductive, and capacitive loads across a wide range of impedances. Common loads include laser diodes, Pockels cells, plasma chambers, solenoids, and spark gap electrodes. Models are available with bipolar output and high-current output for demanding laser diode driver applications. Specify your load impedance and required pulse parameters when requesting a quote. [ a #### Can BNC pulse delay generators be used to drive pulsed power loads? ](#) Yes — while BNC’s pulse delay generators (such as the Model 577) are primarily designed as precision timing instruments, they are frequently used to trigger or gate high-voltage pulsed power systems. In these setups, the DDG provides the precise timing signal that initiates the pulsed power event, with the actual high-voltage switching handled by a separate driver stage. For applications requiring direct high-voltage pulsed output, BNC’s DEI division Pulsed Power product line (PVX and PCX series) is designed specifically for those loads. [ a #### Can BNC’s pulsed power and delay generator products be used together in the same test system? ](#) Yes — BNC’s DEI pulsed power systems and digital delay generators are frequently integrated in the same test setups. The DDG (e.g. Model 577 or 588) provides precise timing control — triggering the pulsed power event at a defined delay and pulse width — while the DEI high-voltage unit (such as the EVO series power supply or PVX/PCX pulsers) delivers the actual high-current or high-voltage output. This combination is used in plasma research, semiconductor testing, laser diode characterization, and synchronization of multiple instruments. BNC’s applications team can assist with integration guidance. [ a #### What are the key safety considerations when operating high-voltage pulsed power equipment? ](#) High-voltage pulsed power systems require careful attention to electrical isolation, grounding, and discharge procedures. Key precautions include using properly rated cabling and connectors, ensuring all personnel are trained on lockout/tagout procedures, maintaining safe clearance distances, and never working alone near energized high-voltage circuits. BNC’s DEI division pulsed power equipment includes built-in safety interlocks and is designed to comply with relevant electrical safety standards. Always consult the product manual and your facility’s safety officer before installation. [ a #### Is the PIM-MINI-20 available from Berkeley Nucleonics? ](#) The PIM-MINI-20 is a specialized pulsed current monitor with limited stock availability. Berkeley Nucleonics does not maintain standard inventory of this model, so lead times and minimum order quantities vary based on production schedules. If you need a PIM-MINI-20 or an equivalent pulsed current measurement solution, contact Berkeley Nucleonics with your application requirements, quantity needed, and desired delivery timeline so we can provide accurate availability and pricing. [ a #### Which Heinzinger power supply is compatible with SiPM detectors? ](#) The Heinzinger PNC 600-300 (600V, 300mA) is not typically required for SiPM-based detectors, which operate at much lower voltages. Berkeley Nucleonics recommends the following Heinzinger power supplies matched to specific detector configurations: for SiPM detectors with integrated electronics (-E3 option), use the PTN 16-10 (0-16V, 0-10A) — these detectors require 5V to 16V at 2-20mA; for SiPM detectors without integrated electronics, use the PTN 65-2 (0-65V, 0-2A) — these require approximately 40-45V at 2-20mA; for PMT-based detectors, use the PNC 1500-40 (0-1500V, 0-40mA) — PMTs require 500-1500V at 2-20mA. Contact Berkeley Nucleonics to confirm the optimal power supply for your specific detector model. [ a #### What is the minimum order quantity for the PCO Series? ](#) The PCO Series laser diode driver modules have a standard minimum order quantity (MOQ) for standalone purchases. However, Berkeley Nucleonics may offer flexibility on minimum quantities when PCO modules are purchased as part of a larger system or bundled with other BNC instruments such as PVX pulsers or Heinzinger power supplies. Contact Berkeley Nucleonics with your specific quantity needs and system requirements for a customized quote. [ a #### What are the similarities between Cerium Bromide and Sodium Iodide detectors? ](#) See this article for details – [https://www.berkeleynucleonics.com/july-27th-2022-cerium-bromide-and-sodium-iodide-detectors](/july-27th-2022-cerium-bromide-and-sodium-iodide-detectors) [ a #### What is Thermal Neutron Detection? ](#) Neutrons do not produce ionization directly in scintillation crystals but can be detected through their interaction with the nuclei of a suitable element. In a 6LiI(Eu) scintillation crystal, for example, neutrons interact with 6Li nuclei to produce an alpha particle and a triton (tritium nucleus), which both produce scintillation light that can be detected. Another Li-containing scintillator is CLYC. Also enriched 6Li containing glass can be used, doped with Ce as an activator. Alternatively, Boron or Gadolinium containing inorganic scintillators can be used but these scintillators are not common. One alternative technique is to construct a large area thermal neutron detector using 6LiF/ZnS(Ag)screens. These can then be read out via green wavelength shifters by PMTs or SiPMs. [ a #### What Types of Radiation Are There? ](#) Alpha radiation, beta radiation, gamma radiation, and x radiation. Neutron radiation is also encountered in nuclear power plants and high-altitude flight and emitted from some industrial radioactive sources. [ a #### When were neutrons discovered? ](#) See this article: [https://www.berkeleynucleonics.com/december-3th-2020-history-neutron-detection](/december-3th-2020-history-neutron-detection) [ a #### How has Gamma Ray Spectroscopy evolved with respect to Isotope Identifiers? ](#) Gamma ray spectroscopy has evolved from large lab-bound NaI(Tl) systems requiring external MCAs, to compact handheld RIIDs with on-board isotope libraries and smartphone interfaces. Modern detectors like the SAM 940+ offer sub-2% energy resolution with real-time field identification. \[Read the full history →\] – [https://www.berkeleynucleonics.com/december-23rd-2020-how-gamma-ray-spectroscopy-has-evolved](/december-23rd-2020-how-gamma-ray-spectroscopy-has-evolved) [ a #### Is your isotope identification equipment compatible with RadResponder? ](#) Our SAM III series of equipment (SAM 950, SAMpack and SAMmobile 150) is compatible with FEMA’s RadResponder network at no additional cost to the end user. [ a #### SAM III Series | What are the advantages of smart phone technology? ](#) The smart phone technology lends itself to spectroscopy with a simplified and intuitive operation. The advantages are many fold: 1. Smart phone operation is wide spread allowing the user to quickly adapt to touch screen use and utilizing many cell phone features. 2. The device (PDA) is a quality product which gives the SAM III products reliable operation with many first-ever capabilities. The display has excellent linearity and resolution with color coded spectra and one-finger operation of the cursor. Many features are automated, for example, auto calibration and stabilization which are clearly displayed. 3. Detaching the PDA (SAM 945, RD120) allows convenient control of the instrument from a distance (bluetooth control). With the RD120 SAMpack monitoring can be clandestine with or without earphones. 4. When monitoring waste or highly active material the user can be at a safe distance (20 feet or more) and have complete control of the spectrometer which includes making measurements, taking multiple acquisitions, manipulating the spectrum, etc. Therefore, the ALARA safety practices are easily accomplished. 5. General cell phone features are incorporated into the operation of the SAM. For example, taking a picture and adding text or video describing details of the source being measured. This added information is included with the report and spectrum. [ a #### SAM III Series | Why is operation in the “Variable Alarm Mode” preferred and why is Auto Variable Trigger employed? ](#) When using the Variable Alarm Mode (as opposed to Fixed Alarm Mode) a low threshold can be set to start the acquisition during a search for radionuclides. A low threshold which triggers the start of an acquisition is important for achieving high sensitivity. However, changes in the background during surveillance can cause false triggers that may result in false identification of isotopes. To prevent false triggers from happening BNC uses a scheme called “Auto Variable Trigger”. This is a threshold adjustment that continuously optimizes the threshold setting automatically. Those performing environmental surveillance will find this mode especially valuable as it allows identification of NORM isotopes with the highest sensitivity possible during changes in NORM. [ a #### SAM III Series | What is the sigma trigger setting for? ](#) The sigma trigger allows a low threshold for sensing a radioactive source while being unaffected by false triggering due to changes in background (sigma indicates standard deviations over background). This provision automatically updates the current background which yields higher sensitivity while eliminating false triggers due to changing ambient background. This feature allows the user to survey a large area without needing to continuously stop and store a new and different background. A sigma setting of 4 is recommended. [ a #### SAM III Series | Why are some isotopes harder to identify at low dose rates/count rates? ](#) The example given here is for a typical background of 7 urem/hr (70 nSv/hr) which corresponds to about 250 gamma counts per second (cps). When a Ra-226 source is detected there will be an alarm at background levels but a firm ID will not occur until the cps reaches about twice the background level (500 – 600 cps for this example). This higher cps level for ID is expected since Ra-226 has many peaks and many are very low in abundance (sometimes referred to as Branching Ratio, Branching intensity or intensity of peaks.) In addition Ba-133 has similar peaks with much higher branching intensities (about 20 times higher) which add to the complexity of identifying Ra-226 especially at low cps. The library is carefully designed to take this into account but moving closer to the source or waiting a little longer for a solid ID is always important (Ba-133 ID may be seen momentarily but will cease as statistics improve). Identifying two or more isotopes each with low abundant lines (peaks) may also require moving closer to the source and possibly waiting longer to obtain good performance. U-238 is another example of a source with low abundant lines and may take up to 30 seconds or more to identify at minimum count rate (<500 cps). Users must realize that the basic specifications which are given for the Cs-137 standard is the result of a very high branching intensity (>85%) – whereas the branching intensity of U-238 lines are less than 1% of Cs-137. It is therefore expected that acquisitions on some sources will take a little longer but it is common practice to use acquisitions of at least 1 minute and to move closer to the source if possible. [ a #### SAM III Series | What is the maximum count rate for the SAM III instruments? ](#) The SAM III instruments have a maximum count rate of 100,000 CPS and 150,000 CPS depending on the amount of background and the number of energy peaks being processed. [ a #### SAM III Series | What isotope libraries are supplied with the RIIDs and Backpack Systems? ](#) Berkeley Nucleonics provides the standard ANSI N42 compliant libraries for SNM, Medical, Industrial and NORM. Also a user defined library is provided. Finally, an expanded ANSI compliant library is available for CeBr and LaBr detector upgrades. New medical libraries and isotopes are updated through the product’s free apps, PeakGo and PeakAbout. [ a #### Can the SAM 940+ detect and identify special nuclear material? ](#) Yes. The SAM 940+ is capable of detecting and identifying special nuclear material (SNM), including HEU and plutonium, using its high-resolution NaI(Tl) or optional CsI detector and on-board isotope library. It meets ANSI N42.34 Type C performance requirements. \[Detailed application note →\] [https://www.berkeleynucleonics.com/march-24th-2022-identifying-nuclear-and-special-nuclear-material-sam-940](/march-24th-2022-identifying-nuclear-and-special-nuclear-material-sam-940) [ a #### Model 940 | How does SAM 940 GN neutron option work? ](#) For routine neutron confirmation, or applications where an integrated, clandestine device is required, BNC offers an Li6 solid state neutron detector internal to the gamma detector module. The benefits include a lower cost, light weight, smaller volume. This detector is available in the SAM 940-2GN and 940-3GN. The Li6 scintillator crystal (neutron detector) is embedded in the NaI scintillator crystal (gamma detector). Both scintillator crystals share the same power and amplification circuits. The MCA processes data from both materials and discriminates Neutron counts from Gamma counts. Secondary confirmation of Neutron counts can be accounted for quickly through the introduction of a tin or lead shield, or a slight retreat in the operator’s position. Contact the factory for additional training. [ a #### Model SAM 950 | What is the battery life of the SAM 950 RIID? ](#) The Model SAM 950 has a highly upgraded power source with rechargeable lithium-ion batteries. These batteries give reliable operation for over 8 hours before requiring recharge. [ a #### Model RD-150 SAMMobile | How can I determine if I need a 2x4x16 or a 4x4x16 inch NaI detector? ](#) BNC generally recommends a 2x4x16 inch detector unless greater efficiency is needed at high photon energies. For energies that include photons from U-235 and Pu-239 there is negligible difference between the two sizes. This means that the photons from both U-235 and Pu-239 are fully absorbed in either size detector. For isotopes like Cs-137 and U-238 some differences begin to show. The photon energy at 2615 keV (which is an indication of highly enriched material) is still easily detected in the 2x4x16 inch detector because the background is quite low in this region. Contact the factory for application specific support. The data for several common isotopes is shown below: ##### 2x4x16 - 100% absorption (abs) at 186 keV (includes all energies of U-235) - 87% abs at 414 keV (includes Pu-239 at 332, 375 and 414 keV) - 75% abs at 662 keV (Cs-137) - 67% abs at 1000 keV (U-238) - 52% abs at 2615 keV ##### 4x4x16 - 100% abs at 186 keV (includes all energies of U-235) - 98% abs at 414 keV (includes all energies of Pu-239) - 95% abs at 662 keV (Cs-137) - 89% abs at 1000 keV (U-238) - 76% abs at 2615 keV [ a #### Model MetRad1 | How do you know if the alarm is radiation or metal? ](#) The MetRad1 has 2 different LED indicators and 2 different alarm tones to notify the operator which type of alarm is present. [ a #### Model 951 | Is there any way to permanently set the sensitivity higher or lower to adjust for constant changes in background levels (around an X-Ray machine, etc)? ](#) The nukeALERT contains an Adjustment Switch that allows you to manually adjust the lowest level sensitivity of the detector. This should not be casually adjusted since it reduces the highest sensitivity of the detector. Usually, this switch is adjusted at the factory or by our tech support team. It is important to track your minimum settings so you don’t end up with 50 nukeALERT’s, each with different sensitivity settings. [ a #### Model 951 | Are there any ongoing maintenance procedures or parts need for the nukeALERT 951? ](#) No. The nukeALERT 951 recalibrates itself on power up and can be operated for many years simply by changing the battery. [ a #### Do you have a device that detects alpha, beta, gamma and x-ray radiation? ](#) The Model 907 measures alpha, beta, and gamma radiation. The device is a health and safety instrument that is optimized to detect low levels of radiation. [ a #### Model 951 | Why does the nukeALERT “recalibrate” as I travel around? ](#) When the nukeALERT is turned on, it calibrates itself to the natural radiation background. When the nukeALERT notices the background has reduced, it will recalibrate itself to improve the sensitivity. When you are traveling, your device may detect a lower natural background environment and recalibrates itself to ensure maximum detector sensitivity. You often see a reduced background count and a recalibration if you take the nukeALERT into a car or truck, for example. [ a #### Does Berkeley Nucleonics sell LaBr3 scintillation detectors? ](#) Yes, Berkeley Nucleonics can supply LaBr3 (lanthanum bromide) scintillation detectors. However, for most applications we recommend considering CLLBC as an alternative. CLLBC offers comparable energy resolution to LaBr3, adds dual-mode gamma and neutron detection capability, and currently provides better pricing and shorter lead times. LaBr3 remains the preferred choice when the absolute best energy resolution is required (as good as 2.8% FWHM at 662 keV) and neutron detection is not needed. Contact Berkeley Nucleonics to discuss which scintillator material best fits your application requirements. [ a #### What are the key specifications of BGO scintillators? ](#) Bismuth Germanate (Bi₄Ge₃O₁₂), commonly known as BGO, is a high-density inorganic scintillator valued for its exceptional gamma-ray stopping power. Key specifications include: very high density (7.13 g/cm³), providing the highest photo-fraction among common scintillators; high effective atomic number (Z=75), making it extremely efficient for gamma-ray photoelectric absorption; excellent chemical resistance and mechanical durability; non-hygroscopic, requiring no hermetic packaging unlike NaI(Tl); and a refractive index of 2.15. BGO is the preferred scintillator for applications requiring maximum detection efficiency in compact volumes, such as Compton spectrometers, PET scanners, and high-energy physics calorimeters. Important supply note (2025): Chinese export restrictions on bismuth, germanium, and other heavy elements have constrained BGO crystal availability, particularly for large sizes. Raw material costs are rising, and some manufacturers have temporarily limited large-format BGO production. Contact Berkeley Nucleonics for current BGO availability and alternative scintillator recommendations. [ a #### What are key specifications of NaI(Tl) scintillation material? ](#) NaI(Tl) — sodium iodide doped with thallium — is the most widely used scintillation material in nuclear spectroscopy and the industry standard for gamma-ray detection. Key specifications include: high light yield (approximately 38,000 photons/MeV), making it one of the brightest inorganic scintillators; density of 3.67 g/cm³, providing efficient stopping power for gamma rays; scintillation decay time of 250 ns, suitable for moderate count rate applications; typical energy resolution of 6.5-7.5% FWHM at 662 keV; and emission wavelength peaked at 415 nm, well-matched to standard PMT photocathodes. NaI(Tl) is readily available in a wide range of standard sizes and is the most cost-effective option for routine gamma spectroscopy. Berkeley Nucleonics offers NaI(Tl) detector assemblies in standard and custom configurations. [ a #### What are common applications for scintillation detectors? ](#) Scintillation detectors are used across a wide range of industries and research disciplines where radiation detection, identification, or quantitative measurement is required. Common applications include: nuclear medicine imaging and PET scanning for medical diagnostics, radiation detection and environmental monitoring at nuclear facilities, high-energy physics experiments and cosmic ray research, homeland security screening and radiological threat detection at ports and borders, oil and gas well logging for geological characterization, X-ray and gamma-ray spectroscopy for material analysis, radiation therapy beam monitoring and patient dosimetry, and industrial process control involving radioactive sources. The optimal scintillator material — NaI(Tl), CLLBC, BGO, or LaBr3 — depends on your specific requirements for energy resolution, detection efficiency, count rate, and neutron sensitivity. Berkeley Nucleonics manufactures complete detector systems for all of these applications. [ a #### Is a NaI(Tl) scintillation detector temperature stabilized? ](#) Yes, NaI(Tl) scintillation detectors can be temperature stabilized, and stabilization is important for maintaining accurate energy calibration. NaI(Tl) crystals exhibit a light output that varies with temperature — approximately -0.2% to -0.3% per degree Celsius — which means the detector’s energy calibration will drift as ambient temperature changes. Common stabilization approaches include digital gain stabilization electronics that automatically compensate for temperature-induced gain shifts, thermoelectric coolers (TECs) for active temperature regulation in controlled environments, and thermally insulated housings for passive stabilization in field deployments. Berkeley Nucleonics offers detectors with built-in digital gain stabilization for applications where temperature fluctuations are unavoidable. [ a #### What are key specifications of CLLBC scintillators? ](#) CLLBC (Cs₂LiLa(Br,Cl)₆:Ce) is an advanced scintillator material with several key specifications: energy resolution as good as 4.1% FWHM at 662 keV, which is superior to the ~7% typical of NaI(Tl) detectors; dual-mode detection capability for both gamma rays and thermal neutrons in a single crystal, eliminating the need for separate detector systems; good light yield and proportional response across a wide energy range; and compatibility with both PMT and SiPM readout. Compared to LaBr3, CLLBC currently offers shorter lead times and more competitive pricing while providing comparable gamma detection performance plus the added benefit of neutron sensitivity. Berkeley Nucleonics integrates CLLBC crystals into complete detector assemblies for radiation spectroscopy, nuclear security, and research applications. [ a #### What is a scintillation detector and how does it work? ](#) A scintillation detector converts ionizing radiation (gamma rays, neutrons, or charged particles) into visible light pulses, which are then detected and measured by a photomultiplier tube (PMT) or silicon photomultiplier (SiPM). The material used for scintillation — such as NaI(Tl), CeBr3, or CLYC — determines the detector’s energy resolution, timing performance, and sensitivity to specific radiation types. BNC manufactures custom scintillation detectors across a wide range of crystal materials for research, defense, nuclear medicine, and environmental monitoring applications. [ a #### What is a Scintillator? ](#) A scintillator is a material that exhibits scintillation, which refers to the emission of light when the material interacts with ionizing radiation. Scintillators are widely used in various fields, including radiation detection, medical imaging, and high-energy physics. Different types of scintillators exist, and some common examples include NaI (sodium iodide), LaBr (lanthanum bromide), CeBr (cerium bromide), and CsI (cesium iodide). These scintillators have distinct properties and are utilized in specific applications. Each of these scintillators has its advantages and suitability for specific applications, depending on factors such as energy resolution, light output, decay time, and cost. Researchers and engineers select the most appropriate scintillator based on the requirements of their particular application. [ a #### What is the significance of Density and atomic number (Z)? ](#) To detect y-rays efficiently, a material with a **high density and high effective Z (number of protons per atom) is required.** Inorganic scintillation crystals meet the requirements of stopping power and optical transparency. Their densities ranging from roughly 3 to 9 g/cm3 makes them very suitable to absorb penetrating radiation (γ-rays). Materials with high Z-values are used for γ-ray spectroscopy at high energies (> 1 MeV). [ a #### What is the significance of Light Output (wavelength + intensity)? ](#) Because photoelectron statistics (or electron-hole pair statistics) play a key role in the accurate determination of the energy of the radiation, the use of scintillation materials with a high light output is preferred for all spectroscopic applications. The scintillator emission wavelength should be matched to the sensitivity of the light detection device that is used (PM, SiPm or photodiode). [ a #### What is the significance of Decay Time? ](#) Scintillation light pulses (flashes) are usually characterized by a fast increase of the intensity in time (pulse rise time) followed by an exponential decrease. The **decay time** of a scintillator is defined by the time after which the intensity of the light pulse has returned to 1/e of its maximum value. Most scintillators are characterized by more than one decay time and usually, the effective average decay time is mentioned. The decay time is of importance for fast counting and/or timing applications. [ a #### What is Afterglow? ](#) To detect fast changes in transmitted intensity of X-Ray beams, such as in CT scanners or luggage X-ray detectors, crystals are required exhibiting low afterglow. Afterglow is defined as the fraction of scintillation light still present for a certain time after the X-Ray excitation stops. Afterglow originates within a millisecond and can last hours in long decay time components. Afterglow in most halide scintillation crystals can be as high as a 5-10 percent after 3 ms. The long duration afterglow in e.g. CsI(Tl) can be a problem for many applications. Afterglow in halides is believed to be intrinsic and correlated to certain lattice defects. BGO, CeBr3, and Cadmium Tungstate (CdWO4) crystals are examples of low afterglow scintillation materials. [ a #### What wavelength is the light emission of a scintillator material? ](#) Each scintillation material has a characteristic emission spectrum, with wavelength and intensity. The shape of this emission spectrum is sometimes dependent on the type of excitation (photons/particles). ![](https://www.berkeleynucleonics.com/wp-content/uploads/wavelength_is_the_light_emission.jpg) ##### Emission spectra of NaI(Tl), CsI(Tl) and CeBr3, scaled on maximum emission intensity. Also a typical quantum efficiency curve of a bialkali photocathode and a Silicon Photomultiplier (SiPm) are shown above. This emission spectrum is of importance when choosing the optimum readout device (PMT / photodiode/SiPm) and the required window material. The graph above shows the emission spectrum of some common scintillation materials. [ a #### Can you explain the variety of mechanical, optical and scintillation properties of various materials? ](#) The most widely used scintillation material for gamma-ray spectroscopy is Sodium Iodide, NaI(Tl). It is hygroscopic and is only used in hermetically sealed metal containers to preserve its properties. All water-soluble scintillation materials should be packaged in such a way that they are not attacked by moisture. Some scintillation crystals may easily crack or cleave under mechanical pressure whereas others are plastic and only will deform like CsI(Tl). See our [Table of Properties](https://www.berkeleynucleonics.com/sites/default/files/products/datasheets/Scintillators%20Physical%20Properties_1.pdf) or [Table of Applications](https://www.berkeleynucleonics.com/sites/default/files/products/datasheets/Scintillators%20Common%20Applications_1.pdf) for material specific comments. [ a #### What is the difference between SiPM and PMT readout methods? ](#) SiPMs are an alternative readout method to standard PMTs. With respect to signal processing and spectroscopic behavior, SiPMs behave differently compared to standard PMTs. The elements are typically 3×3 or 6×6 mm and can be combined into matrices. For applications where a small crystal size and low voltage operations are required SiPM readout can be a good choice. The energy resolution and noise level achievable with SiPM readouts depend on crystal dimensions, scintillation material, and how much area is covered by the SiPMs For larger scintillation crystals, it is important to strategically place as few SiPMs as possible. It is impractical to use too many SiPMs because the capacitive notice on the signal If you are interested in this readout method, please contact us [ a #### Does temperature affect the response of a scintillation detector? ](#) The light output (number of photons per MeV gamma) of most scintillators is a function of temperature. This is caused by the fact that in scintillation crystals, radiative transitions, responsible for the production of scintillation light, compete with nonradiative transitions (no light production). In most scintillation crystals, the light output is quenched (decreased) at higher temperatures. An example to the contrary is the fast component of BaF2 which the emission intensity is essentially temperature independent. The scintillation process usually involves three stages, production, transport and quenching centers. Competition between these three stages and all three behaving differently with temperature creates a complex temperature dependence for scintillation light output. Below is a chart with the temperature dependence of common scintillation crystals. ![](/wp-content/uploads/background_cebr3-1.png) ###### Temperature dependence of the scintillation yield of NaI(Tl), CsI(Tl), BGO and CeBr3 For most applications, the combination of the temperature dependent light output of the scintillator together with the temperature dependent amplification of the light detector should be considered. The doped scintillators NaI(Tl), CsI(Tl) and CsI(Na) show a distinct maximum in intensity whereas many undoped scintillators such as BGO show an increase in intensity with decreasing temperature. The temperature dependence of the Ce doped scintillators LBC, CeBr3 and YAP:Ce is significantly less than that of other scintillators. [ a #### What are the similarities between Cerium Bromide and Sodium Iodide detectors? ](#) See this article for details – [https://www.berkeleynucleonics.com/july-27th-2022-cerium-bromide-and-sodium-iodide-detectors](/july-27th-2022-cerium-bromide-and-sodium-iodide-detectors) [ a #### What are the most important properties when selecting a scintillator for my application? ](#) - Density and atomic number (Z) - Light output (wavelength + intensity) - Decay time (duration of the scintillation light pulse) - Mechanical and optical properties - Cost [ a #### How do I choose the right scintillation material for my application? ](#) Material selection depends on what type of radiation you’re measuring, required energy resolution, operating temperature range, count rate, and cost constraints. NaI(Tl) is the most widely used general-purpose gamma detector. CeBr3 offers superior energy resolution without requiring cooling. LaBr3 provides excellent timing and resolution but is more expensive. CLYC and CLLBC are dual-mode gamma/neutron detectors suitable for SNM detection. SrI2 delivers the highest resolution available in a room-temperature scintillator. BNC’s applications team can recommend the best material based on your specific requirements. [ a #### What factors should I consider when customizing my scintillation detector? ](#) There is a great variety of choices to consider. Selecting the right material, geometry, readout and electronics are only a start. See [https://www.berkeleynucleonics.com/february-11th-2022-customizing-your-scintillation-detector](/february-11th-2022-customizing-your-scintillation-detector) for further reading. [ a #### Are there ways to increase the ruggedness of a detector for outdoor/field work? ](#) Yes – an important aspect of your product selection. See [https://www.berkeleynucleonics.com/february-23rd-2022-ruggedized-detectors-customized-scintillators-field](/february-23rd-2022-ruggedized-detectors-customized-scintillators-field) for further reading. [ a #### What is Thermal Neutron Detection? ](#) Neutrons do not produce ionization directly in scintillation crystals but can be detected through their interaction with the nuclei of a suitable element. In a 6LiI(Eu) scintillation crystal, for example, neutrons interact with 6Li nuclei to produce an alpha particle and a triton (tritium nucleus), which both produce scintillation light that can be detected. Another Li-containing scintillator is CLYC. Also enriched 6Li containing glass can be used, doped with Ce as an activator. Alternatively, Boron or Gadolinium containing inorganic scintillators can be used but these scintillators are not common. One alternative technique is to construct a large area thermal neutron detector using 6LiF/ZnS(Ag)screens. These can then be read out via green wavelength shifters by PMTs or SiPMs. [ a #### What is Radiation Damage in Scintillators? ](#) Radiation damage is defined as the change in scintillation characteristics caused by prolonged exposure to intense radiation. This damage manifests itself by a decrease of the optical transmission of a crystal which causes a decrease in pulse height and deterioration of the energy resolution of the detector. Radiation damage other than radio-activation is usually partially reversible; i.e. the absorption bands often disappear slowly in time; some damage can be annealed thermally. In general, doped alkali halide scintillators such as NaI(Tl) and CsI(Tl) are rather susceptible to radiation damage. All known scintillation materials show more or less damage when exposing them to large radiation doses. The effects usually can only be observed clearly with thick (> 5 cm) crystals. A material is usually called radiation hard if no measurable effects occur at a dose of 10.000 Gray. Examples of radiation hard materials are CeBr3 and YAP:Ce. [ a #### What are the pitfalls of using a pulse generator to drive a laser diode? ](#) [https://www.berkeleynucleonics.com/february-15th-2022-pitfalls-using-pulse-generator-drive-laser-diode](/february-15th-2022-pitfalls-using-pulse-generator-drive-laser-diode) [ a #### BrightSPEC | Is bGamma MCA software compatible with Macs or PCs? ](#) Yes. bGamma is a full spectroscopic package for NaI, HPGe and other spectroscopy applications. It is the only spectroscopy package that is Mac and Windows compliant. [ a #### Are service agreements available for Heinzinger power supplies? ](#) Yes, Berkeley Nucleonics offers multi-year service agreements for Heinzinger high-voltage and low-voltage power supplies, including the EVO and PTN series. A standard 3-year service agreement covers calibration, preventive maintenance, and repair services. Service agreements are currently available for customers within the United States. Contact Berkeley Nucleonics for a service agreement quote specific to your Heinzinger power supply model and configuration. [ a #### Front Office | How do I get a quick quote or expedite an order? ](#) To check price and delivery, to place a Purchase Order, or to expedite an existing order, please call 415-453-9955, email or fill out a [Get a Quote form](https://www.berkeleynucleonics.com/get-quote). Typical response time is less than 2 hours. [ a #### Front Office | Where is the Berkeley Nucleonics headquarters? ](#) ur main headquarters is in California. Our address is 2955 Kerner Blvd, San Rafael CA 94901. We have sales offices throught the United States and in many European and Asian countries. We also have a nationwide network of approved trainers to handle product training and installation. Contact the factory at 415-453-9955 or for your closest resource.