Low cost programmable signal generator

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What is the difference between a 100MHz sin and 100MHz triangle?

You'll be happy if you can find a megabuck one.

As Frank says, I don't think there are any. The low cost "function" generators seem to stop at around 20MHz.

It would probably be cheaper to get a low cost function generator (sine, sawtooth, square) up to 20MHz, and a separate low cost "signal generator" (sine only) up to 100MHz+.

Of course there are new things coming out all the time, so I may be out of date. There are reasonably priced DDS chips capable of this, so perhaps someone has packaged one into a modern, low cost instrument.

I have been looking at the new Tektronix arbitrary function generators

These would do what you want and much more, and are competitively priced for their product class. But hardly student priced (thousands of $) :(

Same as the difference between a 1Hz sine and 1Hz triangle.

Ian

At least a 200Mhz and a 400MHz overtone, likely more.

You'll have a hard time finding a commercial unit that does 100MHz, and if you did you can't afford it. Why do you need 100MHz?

The ones with a keypad to enter the frequency will be a DDS (Direct Digital Synthesis) type.

There are some low cost function gens on eBay like this one:

If you want to roll your own for not much cost then you can try the MAX038 chip for an analog solution, like this one:

Or there are a few DDS chips around for a digital solution like this one:

Analog devices have "demo boards" for their high frequency DDS chips that will give you 100MHz if you *really* need sort of frequency, they cost a couple of hundred dollars and are PC driven only unless you design you own interface.

At $1300, the new Goodwill GFG-3015 is an excellent example of a low cost fully optioned function generator:

Dave :)

for such a wide range, look at the range of NCO's available, you will have to also use a micro to drive them and other odds & sods

enjoy

Have a look around on ebay

You can find some good stuff there ,i got me a working hp3325A ( 0.1hz

Johan

aye, i can recommend soemthing up to 44khz, your soundcard, though u might need a ghz or 2 cpu to keep up. theres plenty of signal generators around,