Found this circuit, what can i make out of this?

[PRR]

I think a basic audio signal source is *vital* for audio testing and experimentation. If I didn't already have several such gizmos handy, I'd use that one. But maybe I been doing this too long.

[armdnrdy]

I think a basic audio signal source is *vital* for audio testing and experimentation. If I didn't already have several such gizmos handy, I'd use that one. But maybe I been doing this too long.

I completely agree....you have been doing this too long! 

Seriously, Early on, I saw the need for certain test equipment. Service manuals for flangers and delay units that include factory calibration and set up procedures call for inserting a sine wave of a specific frequency and amplitude to calibrate bias, feedback, ect.

You can't do that strumming a guitar. 

[merlinb]

What the OP's question reminds me of: