Yahoo Groups archive

MOTM

Index last updated: 2026-04-28 23:35 UTC

Message

Re: MOTM 300 VCO help

2012-11-14 by gooboworks

Ok, I have more information.

It appears that the 1v/octave and the FM2 inputs and their respective pots are working correctly.

I have more info on the problem.   Whenever the EXP/LIN switch is in the EXP position, the FM1 pots has no affect along with the FM1 input voltage.

I noticed another issue.   The SINE wave sounded harsh and it is hot, it measures +14v to -14v.    Definitely something wrong there.

Any thoughts appreciated.

Thanks 
Andy Miller


--- In motm@yahoogroups.com, Richard Brewster <pugix@...> wrote:
>
> Obvious question:  Do the 1V/octave and FM2 inputs work as expected?  If 
> so, then it's just a problem with the FM1 Exp.  If those other 
> exponential inputs don't work, the problem is more central.
> 
> Richard Brewster
> http://pugix.com
> 
> On 11/13/12 12:37 PM, gooboworks wrote:
> > Folks, I just finished building a MOTM 300 VCO.  I have a problem.   the EXP/LIN switch is not acting correctly.  When I have a LFO control voltage in FM1 the oscillator appears to work fine when the switch is in the LIN position.   When I switch it to EXP, the oscillator will does not react, the oscillator acts as if nothing is inserted into the FM1 jack.
> >
> > I am an experienced builder and I have built MOTM 300's before. I know I can email Paul S. on this, but I wanted to hit the list first to see if anyone had any tips on where I might look for an issue.
> >
> > Any thoughts on what might be the problem and where I can look?
> >
> > Thanks
> > Andy Miller
> >
> >
> >
> >
>

Attachments

Move to quarantaine

This moves the raw source file on disk only. The archive index is not changed automatically, so you still need to run a manual refresh afterward.