[sdiy] interlocking switches

[JH.]

No pic solution from my side. (But you already guessed that.)
http://www.oldcrows.net/~jhaible/polykorg/jh_3200_digital_1.gif
The drawing contains two such selectors, so you only need half of the
circuit.
Two 4000 series ICs for 8 channels.

JH.


----- Original Message ----- 
From: "Roy J. Tellason" <rtellason at blazenet.net>
To: "SDIY list" <synth-diy at dropmix.xs4all.nl>
Sent: Sunday, August 14, 2005 9:19 PM
Subject: [sdiy] interlocking switches


> I *know* I've seen this in some service manual or other,  but can't
remember
> where...
>
> Say you have a row of buttons,  and you push one,  an LED lights up.  When
you
> push another,  that light comes on and the first one goes out.  Sort of
like
> the old mechanically-interlocked switches I remember from ages ago.
>
> Posted about this elsewhere,  and have of course the immediate suggestion
to
> throw a processor at it,  which I'm not inclined to do,  and some more
that
> discuss using lots of logic.
>
> Can any of you guys point me toward a circuit like this?  I know there
were a
> fair number of commercial keyboards out there that used such stuff,  rows
of
> momentary-contact switches with LEDs and some toggled on/off,  while
others
> "interlocked" like I'm talking about here...
>
>
>
>
>
>
>