[sdiy] Oberheim Xpander Res fail

[Csaba Zvekan]

OK I replaced tons of 4051's and 4053's and 4016's on the voice board just to find out that it still refuses to tune the "Res". After further investigating the problem It seems my problem is not around the voice board rather around the 5V generation of my DAC. So I'm trying to figure out what really is going on when "Res" is pressed and what components are involved after the Software is " .. .set for E9 and it's resonance control is at maximum (5Volts) " taken from the device manual page 22.
So I believe this is not even happening . How do I trouble shoot this "…E9" and where is this ???
And later it goes into "…frequency is set for E5 …"  ??? where and what is that.  
If I know what and where those lines are I'm getting closer.

Any help greatly appreciated 

Csaba



On 10 Jan 2012, at 13:21, Tom Wiltshire wrote:

> You might have found this already, but if not, here you go.
> 
> T.
> 
> 
> 
> <Xpander Service Manual.pdf>
> 
> On 9 Jan 2012, at 14:12, Csaba Zvekan wrote:
> 
>> Hi Group ,
>> 
>> My Oberheim Expander fails to tune the resonance section but it doesn't tell me what voice. If I force pass it then the synth works just like expected. Even the percussive patches with high resonance work excellent .
>> I'd like to look at some schematics in particular the auto tune feature perhaps some 4xxx CMOS is bad or something. Any suggestions ?
>> 
>> Best regards
>> 
>> Csaba
>> 
>> _______________________________________________
>> Synth-diy mailing list
>> Synth-diy at dropmix.xs4all.nl
>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>