[sdiy] Juno 6 voice problem

[Andrew Simper]

Hi Travis,

If the VCA is being kept high you need to check the control voltage
being sent to it and see how it compares to the other voices. TP6 will
check IR3R01 envelope chip is working, when you say tp6 "goes high"
does it also go low again? If not then it may be a problem with the
gate signal heading to the env chip.

If it does go low then I would work backwards from pin 1 of the ba662
ic24.25.21.22.19.20, until you can find a difference to the other
voices. If there is no difference at pin 1 then your ba662 could be
the problem.

Andy
--
cytomic - sound music software



On 9 July 2013 00:02, Travis Thatcher <recompas at gmail.com> wrote:
> I'm looking at a Juno 6 for a buddy who has a voice issue. The
> envelope on Voice 2 seems to be always on. If I bring up the release
> on the envelope it opens up the filter for that voice and you can hear
> the oscillator drone. I tested the output for that voice on tp6 and it
> goes high when that voice is triggered.  I'm guessing this would be a
> vca issue? Anybody have any ideas on where next to dig in? I was going
> to make sure the vca gain trimmer was okay first - since the one that
> is there different from the other voices and may have been replaced at
> some point.  After that I was thinking the transistors associated with
> the vca (tr5-8).  Any pointers on how to better pinpoint the issue
> would be really helpful.
>
> Thanks!
>
>
> --
> http://www.travisthatcher.com
> http://www.soundcloud.com/travisthatcher
> http://voiceofsaturn.blogspot.com
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