Model 400/500/555
Can I obtain high voltage outputs? The standard pulses are delivered on the front panel. One may choose, on a per channel basis, to select high voltage or TTL/CMOS or the adjustable amplitude output. When one selects the high voltage mode with the output on the rear panel, the front panel output for that channel provides a TTL/CMOS pulse whose timing approximates that of the 35V pulse. The 35V pulse is now calibrated for the right timing. The 35V pulse has an adjustable pulse width up to 1 us. (Back)
What are the shipping weights and dimensions of the 555 Digital Delay / Pulse Generators? For 2 and 4 channel units - 15"x12"x9", 8 lbs., for the 8 channel unit - 18"x12"x9", 8 lbs. (Back)
Can I software trigger the 555? Yes, there is a command in both RS232 and GPIB to trigger the unit. (Back)
Is the "Divide-by-N" feature in selectable in single integer steps? What is the range? Yes, you can input any integer( i.e. input 512 as N to get 1/512 the frequency). The range is 1-50,000. (Back)
Explain the Clock Out Feature? Clock Out, when enabled, provides a TTL 10 MHz clock that is phase locked to the internal 10 MHz clock. Push FUNCTION and MODE twice to get to the clock menu. (Back)
Explain the Clock In Feature? Clock in, when enabled, accepts a TTL 10 MHz clock that will be used as the internal 10 MHz reference clock. This allows the internal clock to be phase locked to an external source. Thus removing the jitter and drift between the two. The down side is that the system clock becomes 10 MHz rather that 80 MHz and therefore the external trigger to output jitter will be nominally 100ns instead of 12.5ns. Push FUNCTION and MODE twice to get to the clock menu. (Back)
Is a master/slave clock feature available on a Model 555? Yes. The clock connector on the rear panel may be set in a Clock Out or Clock In mode. (Back)
What is the threshold adjustment range for the Trigger/Gate Input? 100mV to 10V (Back)
How do I obtain a sub-multiple of the continuous pulses? The 500A has a Divide by N feature, whereby Channel 2"s output after N pulses from the other channels. What"s more Channel 2"s output can have a separate delay and width. The delay for channel 2 with the 500A is referenced to channel 1"s leading edge. (Back)
Can I see the delays and widths of ALL channels on one screen? Yes. The AUXILIARY command will show on one screen the delays and widths for the all the channels. (Back)
Explain the Channel menus? The Channel menus are specific to each channel. You first push the specific channel button. The CHANNEL menus include; Enable/Diable (you may disable or enable any channel), Timing Parameters (sets the width and delay for that channel relative to To), Pulse Configuration (sets polarity, output type and output level), Special Function (each channel may have different modes of operation with continuous, single shot, burst (with its own number of burst pulses) or divide by N (with its own N)), Gated Operation (each channel may be independently gated with its own gate polarity). (Back)
What is the SYSTEM command used for? It sets communication parameters, keypad properties, display properties. (Back)
What are the STORE and RECALL commands used for? Use the STORE command to save to memory entire configurations of instrument settings. Also, you may number and name that configuration accordingly. Use the RECALL command to recall any of the stored settings by number or name. (Back)
What does the RATE command do? The RATE sets the internal clock period that continuous, burst or duty cycle pulses occur at. (Back)
What does the GATE/TRIGGER command do? This selects the operation of the Gate/Trigger Input - it can be used as a trigger, gate or be disabled. You can change the Mode (select disable, edge triggered or level gated), Threshold (sets voltage level), Edge (selects rising or falling edge as trigger), Polarity (selects active high or active low gate). The External Trigger mode is particularly useful. Each External Trigger can start the continuous pulses, a single shot, a single burst or a single duty cycle. The mode that one commonly associates with externally triggering pulse and delay generators is, for the 555, the single shot mode. (Back)
Can I set up special modes of operation on a single channel or on all channels? Yes. The 555 provides features common to all channels and features specific to a single channel. Burst, divide by N, single shot and continuous can be selected commonly or specifically. The operating menus are common to all channels while the channel menus are channel-specific. (Back)
Explain the Operating Menu commands? This menu is common to all channels. The items are; MODE - selects the timing pattern, Continuous - essentially a free-running mode, Single Shot - provides one pulse at the push of the Run button or at the application of an External Trigger, Burst - provides a single burst of N pulses when initiated by the Run pushbutton or External Trigger, Duty Cycle - sets the number of pulses that are on and the number of pulses that are off. A single duty cycle is initiated by the Run pushbutton or External Trigger. This is in effect a divide by N function that is common to all channels. (Back)
How does the Model 555 Menu System work? The human interface was well designed to shorten your start-up time. There are two types of menus - operating menus and channel menus. The operating menus are accessed by pushing the blue (function) button and then the button associated with Mode, Rate, Gate/Trigger, System, Store, Recall or Auxiliary. The channel menus are accessed by pushing a particular channel button (Channel A, Channel B, etc..) (Back)
Can I pull the 555 out of the box and immediately get pulses out? The 555 arrives with a factory default setting programmed into the unit. You will get pulses out immediately upon turning on the instrument and pushing the RUN button. (Back)
Can I use one Model 555 on a bench and in a rackmount? The rackmount on the 555 can be removed and reinstalled in the field easily. You can use one instrument for both benchtop and rackmount applications. (Back)
Can I use one Delay Generator to combine multiple pulses for flash lamps, Q-switches, shutters and cameras? Yes, because the need often exists to have synchronized timing control signals. Also typical is the need for multiple pulses at a node while other nodes have only one pulse. An example of such an application exists is fluid dynamic studies where cameras, shutter, flash lamps and Q-switches are all synchronized to each other. (an example using one Model 555-8c to generate 8 pulses, some combined at a node, some independent -- you can select either an External Trigger or the Internal Trigger generator to give you 8 independent pulses. Some pulses go to independent inputs. The remaining pulses are summed using series diodes to couple the pulses to a common input.) (Back)
Are the units CE marked? Yes, the 400, 500 and 555 are CE marked. (Back)
Can I obtain high voltage outputs? The 555"s offer a 35 Volt option. This option will give you both 35V pulses on the rear panel connectors and the standard pulses on the front panel. (Back)
Can the Digital Delay / Pulse Generators provide long delays and periods? The 400 series provides intervals as long as 100,000,000 seconds. (Back)
I need narrow pulses…What is the minimum pulse width? Risetime? Minimum pulse width is based on slew rate. For example, with 5ns edges, the 555"s TTL output will produce 5ns FWHM pulses. The 400 and 500 are slower devices. If you can tolerate a 1V pulse, the 400 and 500 have a 5ns FWHM. At 10 V, this jumps to a 50ns FWHM. (Back)
How do I obtain complex burst sequences? Modification to the unit allows for insertion of bursts within bursts, nested bursts and looping. (Back)
Can I re-synchronize my free-running pulses to an External Trigger? Pulse trains occur continuously at programmed rate, delay and width settings. A modified unit provides continuous pulses whose sequences are resync"ed to the Ext Trig. (Back)
What is Divide by N? This mode allows a specific channel"s output to be a sub-multiple of the standard continuous pulse rate. When you select Divide by N and specify an N, that channel outputs a single pulse for every N continuous pulses. The Divide by N feature is selected of a per channel basis and the value of N may differ from channel to channel. In addition, the Divide by N pulses may have its own delay and width. (Back)
How do I obtain the lowest jitter? If the lowest jitter is important to you, use one channel to initiate your event and the other channels will be finely synchronized to that one channel. The jitter from the Ext Trig to the outputs is higher than the jitter between channels. (Back)
Can I alternate outputs with each trigger? We provide the option of alternating the signal from any set of connectors with each trigger. This is a modification to the standard unit. With a "two channel" modification, channel 1 outputs every odd trigger and channel 2 outputs every even trigger. (Back)
What is the Storage Setup and Recall Procedure?"’’" Storage Setup and Recall Procedure (Back)
Can I input several triggers and get one delayed pulse for each trigger? We have a modified 500 that does that. It takes up to 5 triggers and provides a delay to each trigger, a delayed OR if you will. The 8-channel 500 can be modified to accept up to 9 inputs to do the same thing. (Back)
Are Labview drivers available? Our customers have succeessfully integrated labview drivers using our product. Send us your requirements. (Back)
