[sdiy] Analog keyboard control voltage circuitry question

[harrybissell at copper.net]

You could use a constant current source if the keys
are set to ground the resistive string... or a voltage
source if the keys pick off a voltage into a suitable
(read WAY) high impedance buffer.

I prefer the current source with grounded keys, so that
pressing two keys does not generate a strange in-between
voltage

There should be 1/12th volt across each resistor (or you
could use gain in the buffer stage to adjust it to suit

H^) harry




>
>
>
>---- Original Message ----
>From: prowlerraven32 at hotmail.com
>To: analogue at hyperreal.org, synth-diy at dropmix.xs4all.nl
>Subject: RE: [sdiy] Analog keyboard control voltage circuitry
>question
>Date: Wed, 11 Apr 2007 17:27:38 -0400
>
>>04/11/2007
>>
>>When you assemble an analog keyboard using the 100 ohm resistive
>voltage 
>>divider network, what should the maximum voltage be that enters the
>divider 
>>network so that each octave measures 1.0 volt and so on as you go
>from left 
>>to right on the keyboard ? Also, should a constant current source be
>used or 
>>can you use a voltage regulator to do the same thing ?
>>
>>Logan
>>
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