Vintage Synth Repair

Ethan,

Here's the link to the 4072 schematic:

http://www.netcontrol.fi/~jocke/arptech/pdf/4072.pdf

A lot of the submodule schematics are also there!!!

Good luck!

Matt

> > Hello,
> > 
> > I am trying to identify 
> > the two ICs on the ARP
> > 4072 submodule.  The
> > schematic shows no ICs
> > nor does the parts list.
> > 
> > TIA,
> > 
> > Ethan
> 
> Ethan, both IC's are linear types. One is the LM3900N (national 
> semiconductor) and the other is a LM1458 (also national part) you 
can 
> also use a RC4558 instead of the 1458. The LM3900 is drawn as 4 
> seperate amps in the schematic because there are four OP Omps in 
the 
> one 14 pin IC package.  You should be able to get these from 
Digikey 
> on line. (digikey.com?)
> 
> Regards,
> John