Re: FG-504 not-so odd behavior


keantoken
 

10*10^2=1KHz, so it seems to be partly working. All functions should be 1KHz so something is off.
Check that the oscillation is coming from the oscillator. The oscillator may be behaving normally and the output amp is oscillating on it's own. If they are both oscillating at 25MHz then I would look at the decoupling caps or a broken ground causing feedback between the output amp and the oscillator.
I would try a little harder to identify the fault in the non functional one. It could be that when you find the problem it will suddenly work fine with no issues. On Saturday, July 11, 2020, 09:51:04 AM CDT, John Ferguson via groups.io <jferg977=aol.com@groups.io> wrote:

with the FG 504 set at start freq 10, stop freq 40, multiplier at 10^2,
sweep off,

measured on my 2445b, Sine freq 982.3 Hz, Sawtooth 975.9 Hz and Square
wave 24.5 mHz.

The square wave is an asymmetrical  sine wave, not the Sawtooth I was
expecting.

Since I have two of these things and this one at least does this, and
also the sweeps and other functions, all except a square wave, and the
other one does nothing, this might be the one to fix.

What do you think?


john

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