SergeModular

<sigh> Me and my beat up Serge panel....

Now I'm suspicious of the power supply. I hooked it up today, just to check
the basic functionality of the PS, and lo and behold: When I hook a DVM to
any of the PS pins - + 12, -12, or even 5 V - I hear an audible change in
the oscillator pitch. PS voltages look ok, if not well calibrated: they're
off by ~100 mV, not symmetric. But that doesn't bother me anywhere near as
much as the oscillator pitch change.

How much current should I expect a single panel to draw? My supply is
supposed to supply 400mA at both + and - 12 v. Seems like it should be
enough.


Jim Johnson
jamos@...

Could the problem possibly be with the DVM?
Try putting like a 5k resistor between +12 and ground, see if that makes the
oscillator drift.

John P.

Jim Johnson wrote:

>Could the problem possibly be with the DVM?
>Try putting like a 5k resistor between +12 and ground, see if that makes
>the
>oscillator drift.

My god, I have to worry about the DVM too? :')

Good point, though. I'll try that, and will try another DVM too.

BTW, what lead me here was observing that turning certain pots (filter
frequency, wave multiplier VC pot) full clockwise caused the pitch to drop
about a semitone.

Jim

*********** REPLY SEPARATOR ***********

On 10/1/02 at 8:08 AM John Papiewski wrote:

>Could the problem possibly be with the DVM?
>Try putting like a 5k resistor between +12 and ground, see if that makes
>the
>oscillator drift.
>
>John P.
>
>Jim Johnson wrote:
>
>> <sigh> Me and my beat up Serge panel....
>>
>> Now I'm suspicious of the power supply. I hooked it up today, just to
>check
>> the basic functionality of the PS, and lo and behold: When I hook a DVM
>to
>> any of the PS pins - + 12, -12, or even 5 V - I hear an audible change
in
>> the oscillator pitch. PS voltages look ok, if not well calibrated:
>they're
>> off by ~100 mV, not symmetric. But that doesn't bother me anywhere near
>as
>> much as the oscillator pitch change.
>>
>> How much current should I expect a single panel to draw? My supply is
>> supposed to supply 400mA at both + and - 12 v. Seems like it should be
>> enough.
>>
>> Jim Johnson
>> jamos@...
>>
>>
>> To unsubscribe from this group, send an email to:
>> SergeModular-unsubscribe@yahoogroups.com
>>
>> Keep on Patchin'!
>>
>>
>> Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
>
>
>
>To unsubscribe from this group, send an email to:
>SergeModular-unsubscribe@yahoogroups.com
>
>Keep on Patchin'!
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/


Jim Johnson
jamos@...