Cheap tone generator (kinda funny)

[rake]

I was assembling a tone generator kit the other day and
my friend's nephew was hanging around. He has no male
influence in his family so he's kind of latched on to me.
He looks like "Brick" form the TV show "The Middle". He's 12.

Anyway, I explained to him what I was doing and why it was needed
and he looked at me puzzled for a good minute and then he says, "why
can't you just use that cheap little casio keyboard on the shelf over there"?
and points at one of them cheapo little keyboards.

So, why not is the question. LOL! 

[shooter]

why not is the question

as long as you can control amplitude, should be fine.  Frequency really isn't that important, as long as it's stable. 

[jjasilli]

This is a loaded question: tone generator vs. signal generator.  If all you want to do is test that signal is properly passing, you could use anything such as a guitar, keyboard, radio, cassette player, etc.  It would be better to use a source with a continuous output, so guitars and keyboards are not the best source, but better than nothing.  Except to test reverb, for which isolated spikes of signal is better (I use a Momentary On SW).


For more in-depth testing, you want a signal generator or function generator that can produce proper wave forms.

[PRR]

You really want to produce/reproduce a Musical Instrument.

Is the CasioTone a "musical instrument"? Opinions vary.

Maximum Sine Power and Frequency Response are really best done with a steady Sine. Even if the Casio's "organ" is steady, it is probably more reedy than Sine, throwing several octaves of overtones without plumping-out the fundamental.

But if you are familiar with the CasioTone sound on a good system, many faults in a System Under Test will be apparent to a player's ear.

And the keyboard technician won't yell at you for holding-down the Casio key with Vice-Grips.

[mwelch55]

I use my Smart Phone as a signal generator.  There are several free apps that do this.  Mine does Sine, Triangle, Saw tooth, Square Wave, and NSE (white noise, pink noise, and brown noise).

I made a cable that connects my phone's audio output to the input of the amp.  Works great.  No need to build a signal generator (unless you want to).