Oops. I meant pins 4 and 10, not 4 and 5.
Sorry.
--------------------------------------------
Sorry.
--------------------------------------------
On Wed, 8/24/16, Bob Grieb bobgrieb@yahoo.com [PolySix] <PolySix@yahoogroups.com> wrote:
Subject: Re: [PolySix] Re: Trying to Restore a P6.
To: PolySix@yahoogroups.com
Date: Wednesday, August 24, 2016, 9:48
One thing to mention... When you see a signal
that looks wrong at the output of
a logic gate, the first thing to do is look at the inputs to
that gate. A floating or
incorrect input can cause the output to be wrong. Also, if
the gate is being
loaded down, that can affect its output. To check for a
load issue, with the synth
powered off, measure from pin 4 to ground, and also from pin
5 to ground with a
multimeter in the ohms position. Keep the polarity of the
leads the same for
both measurements. The readings should be similar, since
both feed the INH inputs
of 4051 chips.
IC23 contains four gates. Of course, if one is bad, then
the whole chip would be
replaced. Just saying that each of the four gates has two
inputs and one output
and they act independently.