Vintage Synth Repair

The 3821 is similar to the CA/LM3046 NPN transistor array, and can be substituted. Both 
chips were used in the Minimoog. If you just swap the two 3821's with one another you 
can see if the fault changes, ie: the VCO fault moves, and this will let you know if one of 
the chips is faulty. As I said before, watch the orientation as one chip will be upside down.


--- In vintagesynthrepair@yahoogroups.com, "martinreuter" <FrauReuter@...> wrote:
>
> --- In vintagesynthrepair@yahoogroups.com, "thirteentech" <thirteentech@> wrote:
> >
> > Probably the top CA3046 has failed on the VCO board. You can swap the 2 of them to 
see 
> 
> Uups.... I can only see two "3821" Chips - they are labeled "GG 3821N 7323". The other 
8 
> Chips seem to be all 741 OpAmps - is this right? They are looking different, two are on 
> sockets, six are directly soldered. Can I swap the 3821 with brandnew 3046?
> And: I found four Electrolyte Caps on my board - one 33µF, two 4,7 µF and one 2,2µF. 
All are 
> on the left side over the left contact-row....
> Board is marked "3251" with felt-marker.
> Thanks + Greetings
> Martin
>