Hi Peter,
I don't have an A116, but if it is anything like the A-136 then this
sounds terribly like the ghost of '150 bleed-thru revisited',
discussed at length some weeks back. My guess would be that if the 116
*is* like the 136 and has the capability of amplifying the input
signal greatly, then the signal into the 150 may be more than +/- 8V,
which we know it is very unhappy with! If you have a scope and can
check out the size of the signal you are passing into the 150 (do it
*without* the connecion to the 150 being made, as otherwise the diodes
in it will make it seem like about +/- 8.7 V, whereas in fact it could
be higher) then I would be most interested to hear if this is the case
or not. I still don't appreciate why the FET circuitry in the 4053
chip behaves as it does under such conditions, but I shall continue to
seek an answer - today I printed yet another 4053 datasheet, unlike
the others I have this one shows the exact configuration of
transistors in the switch, so I may yet be able to work it out!
Tim
[The views expressed above are entirely those of the writer and do not
represent the views, policy or understanding of any other person or
official body.]
> Connect a sine into the A-116. VC the shift with a ramp LFO.
> Listen to it. You will hear a tiny bit of waveshape modulation,
> nothing to go bats over.
>
> Take the output of the A-116 and route it into the INACTIVE I/0
> jack of the VC switch (the one in which the LED is OFF). do not
> connect a VC into the switch, let it stay in that state. Listen to the
> output of the VC switch.
>
> You will hear an incredible amplification of the waveshaping
> effect now. I have no idea why this is happening. If there is no
> VC into the switch in order to connect the output (wiper) to the
> normally open contact (the I/0 without the LED on), then you
> shouldn't hear a damn thing....but you do. I tried it on both the
> upper and lower VC swtch, worked like a charm.
>
> try it,m you might like it.
>
> best,
>
> Peter Grenader