I know that this does not have to do with arduino, but....
I want to make sure before i buy this, that this function generator is capable of making an AC signal.
Output Waveforms: 5V TTL Square Wave and selectable Sine or Triangle Wave
I could easily be wrong here, but I think the above means DC only. Perhaps if there was a way to do the Sine wave, but subtract 2.5V from it, so instead of 0 to 5V, it goes from -2.5V to +2.5V. But that's not what you get out of a wall socket if that's what you want.
Good luck!
You can see in the schematic that it has a 1/2 VCC virtual ground circuit and the output of that is being used as one side of the signal output terminals. That would allow a signal to swing above and below the virtual ground. In fact, following the links on that Sparkfun page to Nuxie's website leads you to a page that states:
The redesign includes a buffered virtual ground circuit provided by the LM741 Op Amp, which sets a fixed voltage half way between the input voltage and ground. This is then used as the virtual ground for the sine and triangle wave outputs from the "WAVE_OUT" connector, providing an output centred around 0V.
So it IS capable of producing AC with no extra hardware, Right?
What's so great about an AC output?
Simply by connecting a signal through a capacitor (this is known as AC coupling) any single ended signal (0 to +v) becomes an AC signal (-v to +v).
A few comparators, a 555, some RC circuits and a few trimpots can do sine, square, triangle and sawtooth generation. I got a sub-400 kHz circuit going in a few hours ;D
What do you mean by "AC Signal"?