[sdiy] Welcome to the Twilight Zone

[Peter Grenader]

Late had nothin; to do with this one...i wasn't dreamin!


> Here's the clue :
>> Thought I'd share a bit of bizarro behavior which occurred late last night.
> 
> ____________________________________________________________^^^^^^^^^^^^^^^
> 
> I never do anything that late because by brain starts thinking things should
> be the other way around to what they are, or are around the other way to
> what they should be.
> 
> Either that, or you accidently shorted out an inverter in the input summer.
> this thing is vero after all.
> 
> Ken
> 
>> When putzing around with the prototype Plan B (vector board) all of the
>> knobs except the PWM and FM attenuator - the Freq, fine tune, even the two
>> bipolar freq VC attenuators - suddenly operated in reverse.  Turning the
>> freq pot CCW made the pitch higher.  Turning a freq VC attenuation pots
>> fully CCW processed the VC fully positive (should be the other way around).
>> 
>> Turned the power off - still there.  repeated that a few times - still
>> there.  So then I put my VC Input through an external processor to invert in
>> before it went to the VCO to see if I could fake the VCO out and when
>> turning the offset knob on that processor in a  positive (more voltage)
>> direction, I suddenly noticed that the controls returned the 'normal'
>> operation on the VCO.
>> 
>> They are all running off the same supply.  However, in the name of science
>> and unparalleled universes, all of the effected controls do run through the
>> same op amp internally (they are summed).
>> 
>> Too weird and yes, I did check for flying donkeys outside and no, my cat did
>> not begin to bark during this time.
>> 
>> Now off sign to going I'm,
>> 
>> 
>> - P
>> 
>> 
> _______________________________________________________________________
> Ken Stone   sasami at hotkey.net.au or sasami at cgs.synth.net
> Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
>