one thing to keep in mind is that CA3140s are super delicate ICs.
They are very sensitive to static, but it wouldn't surprise me if
hooking up power in reverse was too much for it to handle.
Romeo
They are very sensitive to static, but it wouldn't surprise me if
hooking up power in reverse was too much for it to handle.
Romeo
On Nov 4, 2006, at 6:08 AM, stiebz wrote:
> No chips are hot ( and nothing smells burned )
> The TL072 seems to working fine, output 7 follows the frequency
> settings, but on the CA3140 I always measure 0.56 V on pin 2 and 1.1
> V on pin 6 regardless of the frequency setting. Would this indicate
> a faillure on the CA3140 or the LM394 ?
> thanks !
> steven
>
> --- In cgs_synth@yahoogroups.com, sasami@... wrote:
> >
> > Test #1 - feel if any chip is getting hot. If it is, replace it.
> >
> > Ken
> >
> > >when i wanted to test my bin-n-tic, i incidently switched + and -
> > >power supply. after i fixed the problem, I have no sound
> whatsoever.
> > >I measured 1.1 volt between pin6 of the ca3140.
> > >Is there any part(s) that is the most likely to be damaged ?
> > >thx,
> > >steven
> > >
> > >--- In cgs_synth@yahoogroups.com, "kopernig" <6079smith@> wrote:
> > >>
> > >> yes, i noticed the diode and put in a jumper... but still no
> joy. i
> > >> don't have a scope (yet) but the voltage on pin six of the
> ca3140
> > >is
> > >> just under 1 volt. with an audio probe i can (barely) hear a cv
> > >click.
> > >> so the vco is not oscillating. i can't figure out why the 2n2
> > >> capacitor seems to be shorted... there's no resistance between
> the
> > >> source and drain of the fet. nothing is physically shorted. a
> dead
> > >> fet? any ideas?
> > >> andrew.
> > >>
> > >
> > >
> > >
> > >
> > >
> > >The CGS Modular Synth home page: http://www.cgs.synth.net/
> > >
> > >Yahoo! Groups Links
> > >
> > >
> > >
> > >
> > >
> >
> __________________________________________________________
> __
> > Ken Stone sasami@...
> > Modular Synth PCBs for sale
> <http://www.blaze.net.au/~sasami/synth/>
> > Australian Miniature Horses & Ponies
> <http://www.blaze.net.au/~sasami/>
> >
>
>
>
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