Cgs synth

Not sure if this is the best way to do this ? but figured if someone in the future searches better to have a few problems in 1 thread.

Anyhow, i have 1 (1/2 of the board) of my dusg's working perfectly and the other not working at all as expected.
The problem is no recognition of a trigger input or signal in for that matter unless i have the fall pot full cw then it seems to go into a slow self cycling.It needs a trigger to start this but does not sync with the trigger at all.As soon as i back off to about 2-3 o'clock it stops.

These are the things i have checked/verified against the working half:

-All ic;s getting and sending the same voltages as working half
-Diode orientations
-resitor values
-Transistor orientation,proper part,voltages the same as working half
-continuity through path of trig in to output
-checked for solder bridges

I'm out of ideas so i will really appreciate it if someone has some advice !

Thanks, Tony

--- In cgs_synth@yahoogroups.com, richmolindarius@... wrote:
>
> Fully agreed. The USG is my fave by far with the SSG following up in a close 2nd. :D
>
> On 2012-10-11, at 12:06 AM, Stephen Richards wrote:
>
> > My all time favourite Serge function block , DUSG rocks.
> >
> > ________________________________
> > From: Rico Loverde
> > To: cgs_synth@yahoogroups.com
> > Sent: Thursday, October 11, 2012 1:51 PM
> > Subject: Re: [cgs_synth] Re: CGS114 DUSG problems/troubleshooting
> >
> > awesome!!!
> >
> > On Wed, Oct 10, 2012 at 7:26 PM, ch1nard wrote:
> >
> > > **
> > >
> > >
> > >
> > > okay awesome, that was totally it
> > >
> > > Now other than the fact that i have the pots wired backwards DUSG seems
> > > functional!
> > >
> > > --- In cgs_synth@yahoogroups.com, "ch1nard" wrote:
> > > >
> > > > ah yes, you appear to be correct good sir :)
> > > > this would be reverse orientation for all trannies? (2N3904 and 2N3906)
> > > >
> > > > i will switch them around after i get home from work and see if that
> > > fixes things up.
> > > >
> > > > might need to hit up the parts store on the way home in case i pooched
> > > any of them from being in backwards
> > > >
> > > > --- In cgs_synth@yahoogroups.com, sasami@ wrote:
> > > > >
> > > > > Also make sure you are using the right sort of tranny! I had people
> > > with
> > > > > this problem on another project - and they had used the wrong sort of
> > > tranny.
> > > > >
> > > > > >Are the trannies situated like the silk screen on the pcb or
> > > reversed? They
> > > > > >should be reversed.
> > > > > >
> > > > > >
> > > > > >
> > > > > >On Tuesday, October 9, 2012, ch1nard wrote:
> > > > > >
> > > > > >> **
> > > > > >>
> > > > > >>
> > > > > >> Okay, i have been staring at this for almost a week without making
> > > any
> > > > > >> progress so its time to start asking around for help on figuring
> > > out what
> > > > > >> might be wrong with my DUSG build
> > > > > >>
> > > > > >> I am running this off +/-15v power supply and i have all the
> > > connections
> > > > > >> appear to be correct with no magic smoke escaping
> > > > > >>
> > > > > >> What is happening is that the output lights are lit up constantly.
> > > > > >> When i hook it up to a scope it appears that both halves are cycling
> > > > > >> (triangle) at about only 300mV p/p
> > > > > >> -fiddling with the rise/fall gives minor variations but is still a
> > > > > >> triangle. (never hits saw or ramp)
> > > > > >> -feeding LFO into VC in shows the same minor variances as fiddling
> > > with
> > > > > >> the rise/fall knobs. bipolar control seems to work
> > > > > >> -feeding a signal IN combines the signal with this triangle
> > > oscillation
> > > > > >> -trig and end do nothing
> > > > > >>
> > > > > >> now everything 'appears' to be wired up correctly and there were a
> > > couple
> > > > > >> of lifted pads that i was able to jumper patch around.
> > > > > >> building this as part of a 'best of cgs' BOG panel, so the wiring
> > > is well
> > > > > >> documented.
> > > > > >>
> > > > > >> I have verified +/- voltage being delivered to all the TL072's and
> > > > > >> verified + voltage for the LM3900's
> > > > > >> ground appears to be delivered as well.
> > > > > >> all the trans are correct value and orientation (2N3904 and 2N3906)
> > > where
> > > > > >> applicable
> > > > > >>
> > > > > >> Anyways, eyes are too tired to look at this anymore tonight...
> > > > > >> time to smoke a bowl and watch some doctor who.
> > > > > >>
> > > > > >>
> > > > > >>
> > > > > >
> > > > > >
> > > > > >--
> > > > > >________________
> > > > > >rico loverde
> > > > > >415.596.6255
> > > > > >ricoloverde.com
> > > > > >
> > > > > >
> > > > > >[Non-text portions of this message have been removed]
> > > > > >
> > > > > >
> > > > > >
> > > > > >------------------------------------
> > > > > >
> > > > > >The CGS Modular Synth home page: http://www.cgs.synth.net/
> > > > > >Yahoo! Groups Links
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > __________________________________________________________
> > > > > Ken Stone sasami@ otherunicorn@
> > > > > Modular Synth PCBs for sale
> > > > > Australian Miniature Horses & Ponies
> > >
> > > > >
> > > >
> > >
> > >
> > >
> >
> > --
> > ________________
> > rico loverde
> > 415.596.6255
> > ricoloverde.com
> >
> > [Non-text portions of this message have been removed]
> >
> > ------------------------------------
> >
> > The CGS Modular Synth home page: http://www.cgs.synth.net/
> > Yahoo! Groups Links
> >
> > [Non-text portions of this message have been removed]
> >
> >
>
>
> [Non-text portions of this message have been removed]
>