[sdiy] The fatman is finished...

[Gabriel Lindeborg]

Hi Scott!

Scott Gravenhorst wrote:

> Vss to Vcc ?  Do you mean Vcc to ground?  Noise should be rather low, well under
> 0.5 volts AC.

Vss is circuit ground, the same as GND as I understand it...

 > I see.  Well, a simple check would be to get a new 9 volt battery and 
 > test it. It should read very close to 9 volts with zero volts on the
 > AC scale. If not, the meter needs to be fixed, battery replaced or
 > used either as a wheel chock or as a target for pistol
 > practice.

Cheap dmms, as mine, show 9V-ish DC and 18V-ish AC (or 0V if switch the 
cables) on a 9V-ish battery. I think they just double the measurement 
and do some simple intregration. The AC power supply I'm using measures 
a fine 13V-ish AC. Anyway I could not hear any low frequency sound (I'm 
on 50Hz/230V-ish) with a signal tracer.

//Gabriel - Back to suspecting the eprom and scrutinizing the solderings 
and components.