Schematic wanted: Crest ultrasonic cleaner

[Gary Walters]

Crest model 4G-250-3, early 90's vintage.

Part numbers have been sanded off all ICs.

It would be great to find a schematic...

Thanks.

 

[N_Cook]

On 28/05/2014 21:54, Gary Walters wrote:

Crest model 4G-250-3, early 90's vintage.

Part numbers have been sanded off all ICs.

It would be great to find a schematic...

Thanks.

So they will not have released a schematic.
Perhaps Google/Images with something like
"ultrasonic cleaner" pcb
and maybe find something rebadged, with extant markings.
As the power side of UCs seems to be unsually IC free, even more likely
in 1990s, any ICs would probably be just for timing and control, so
isolatable if lucky

 

[N_Cook]

Plus side of IC grinding is that they probably used industry standard
CMOS/555/etc rather than ASICs/PICs and similar that would need no
sanding off

 

[Gary Walters]

Plus side of IC grinding is that they probably used industry standard
CMOS/555/etc rather than ASICs/PICs and similar that would need no
sanding off

The DIP-8 I'm focusing on right now looks like it might be a standard dual
op-amp. Analyzing the circuit to see if there's anything special that the
op-amp needs to handle...