[sdiy] CVs to an old Radioshack Reverb

[Happy Harry]

Lets guess what you have...

1) The echo time (or whatever they called it) will be setting the
frequency of a high freq. clock that runs the BBD. It is probably not
voltage controlled.

A lot of times a variable resistor is made with a pot by shorting
the wiper to one end. This assires that even if the wiper goes open
(common failure) that the resistor will go only to the full value,
not infinity.

2) The Depth (whatever) of the effect probably mixes the effect
signal with the input signal. Also probably not voltage controllable.

3) The Reverb (maybe feedback or whatever) will send some effect from
the BBD output back to the input (a feedback loop). Probably not voltage 
controllable.

Most stuff just isn't voltage controlled by design...and you need to
do special things to make it happen. Sometimes more trouble than it is worth 
in the long run.

But its good to study what they HAVE done in the circuit. Its good to
learn techniques that work.

Good Luck

H^) hary


>From: "Rhen, Kris" <krhen at stucki.com>
>To: "'Happy Harry '" <paia2720 at hotmail.com>, "Rhen, Kris" 
><krhen at stucki.com>,   "'synth-diy at dropmix.xs4all.nl '" 
><synth-diy at dropmix.xs4all.nl>
>Subject: RE: [sdiy] CVs to an old Radioshack Reverb
>Date: Tue, 16 Oct 2001 18:16:07 -0400
>
>Thanks Harry,
>Don't variable resistors only have two connections?  Aren't these sorts of
>controls not AC typically?  I'll dig into the PCB and see what I can see.
>Thanks again
>KRIS
>
>-----Original Message-----
>Hi Kris....
>
>Watch it... knobs are not "just" voltage dividers. They are only
>voltage dividers in circuits where you already have voltage control
>built in.
>
>Sometimes they are variable resistances... sometimes AC voltage
>dividers...
>
>
>**********************************************************************
>This email and any files attached are confidential and
>intended solely for the addressee.  This email message
>has also been swept for computer viruses by
>MIMEsweeper  (www.mimesweeper.com)
>**********************************************************************


_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp