Vintage Synth Repair

http://www.matrixsynth.com/blog/media/Moog/MemorymoogSchematics/
 
all the 4051's have been swapped out by someone before me...in fact nearly every IC except for the expensive IC's have been swapped out in this synth. Everything is sockets...so it's easy to do.
 
Like I say it doesnt appear to be one pot...

--- On Fri, 29/8/08, paintingwithsound <cfmh@xtra.co.nz> wrote:

From: paintingwithsound <cfmh@...>
Subject: [vintagesynthrepair] Re: Memorymoog repair
To: vintagesynthrepair@yahoogroups.com
Date: Friday, 29 August, 2008, 3:47 AM






If one pot is doing it then check that pot and track leading to it. If
three are doing it then look for a dud 4051 or similar (haven't seen
the schematics - copy anyone?), if all pots are doing it then the a/d
is faulty.

--- In vintagesynthrepair@ yahoogroups. com, Philip <eggwheatis@ ...> wrote:
>
> Hi Scott, I'll look at that...but it doesnt seem to be caused by a
single pot...I have just sprayed every single pot...no difference. 
> Â 
> Another symptom: It shows the stored pot value on the left and the
actual value on the right. One pots stored value was 31...well i
started turning another pot whose stored value was 49 and as I turned
it slowly the stored value would flicker back to 31..if i turned it
slowly i could make it step between 31 and 49.  It's like data lines
are bleeding into one another. Or like a certain mix of positions of
pots confuse it....
> Â 
> It's hurting my head this one...
> 
> --- On Fri, 29/8/08, scott frye <painintheamp@ ...> wrote:
> 
> From: scott frye <painintheamp@ ...>
> Subject: [vintagesynthrepair ] Re: Memorymoog repair
> To: vintagesynthrepair@ yahoogroups. com
> Date: Friday, 29 August, 2008, 12:29 AM
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> If the same pot is the one that's sticking ( locking up the values)
Spray the heck out of it with some de-oxit.
> If that doesnt work, find out which A / D lines and IC connect to
THAT pot.
> Is the CLK strobing that chip properly? If it's sampled back at the
micro is the clock OK for the micro?
> Just some thoughts w/o looking at the schema.
> 
> Problems like that also occur on the SIEL DK600 and Opera.
> 
> 
> 
> 
> Scott  Frye
> AudioFixation
> Consumer / Pro Audio Repair
> Southern VT 
> 
> "Resistance is futile but.....
> Impedance is much more complex"
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Send instant messages to your online friends
http://uk.messenger .yahoo.com
>

 













Send instant messages to your online friends http://uk.messenger.yahoo.com