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Schematic needed for square wave generator. Answered

I need a schematic and the code for a square wave generator, with the following specs (although it is a bit specific)
Repition Rate (external trigger, 20 Hz 200 Hz 2KHz 20 KHz 2 Mhz and 5 MHz) controlled by a rotory switch.
a vernier (pot) controlling pulses per second.)
a single shot button (N.O. push button)
external trigger (BNC Connector)
Delay (Rotary Switch)  .1, 1, 10, 100, 1k, and 10k microseconds
Vernier (pot) for the delay
a sync output (BNC Connector) with a toggle switch for polarity.
double or single pulse on the output (toggle switch)
polarity selection on the output (toggle switch)
gate on off (BNC connector and toggle switch)
10db step (on or off toggle)
50 ohm load on or off (toggle switch)
rise and fall time (pot)

Any help would be greatly appreciated, as this is a bit specific. I only need a schematic, and everything else i can take care of.

Once again, Thanks for the help.


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9 years ago

BTW, the easiest way to do it these days may be to program a microcontroller and send it configuration commands from a PC, rather than trying to deal with tweaking all of this at the analog level. Even with timer chips.

Of course you'd need a microcontroller fast enough to execute the control loop at the necessary frequency while watching any realtime inputs, and to respond with the required speed after your trigger event comes in. And programming for precise timing *and* interaction is tricky. But it still feels like it might be easier than implementing all those features in a more traditional manner.


9 years ago

What "orksecurity" said, and more. If you are trying to build a copy of something commercial, you are going to

(a) spend more on components, board fabrication and labor than the commercial unit costs;

(b) end up with something where you don't know the calibration;

(c) end up with something where you have to invest in troubleshooting and maintenance yourself, rather than having warranty support.

Unless you're the PI for your lab (and therefore make the budget decisions), I suggest you take this plan up the food chain a couple of steps and get it signed off.


9 years ago

It sounds like you're trying to avoid buying a very specific piece of lab equipment. Somewhat overspecified in terms of being a complicated object where you may not actually need all those features or need them in exactly that form -- "controlled by a rotary switch" probably does not actually matter, for example -- and underspecified in that you haven't said how precisely it needs to be calibrated or how stable it needs to be.

I have no idea what you mean by "double or single pulse" from a square wave generator, unless you mean you want the one-shot pulse button to also be able to produce two pulses.

It isn't at all clear what signal you want on the synch output..

If you *are* trying to reproduce a commercial object, why not just give us make and model number rather than making us try to guess?