[sdiy] Pratt-Reed Mechanisms

[John L Marshall]

If the contacts are gold plated then do not use an eraser. Sorry.

----- Original Message -----
From: The Old Crow <oldcrow at oldcrows.net>
To: Gavin Muir <gmuir at sympatico.ca>
Cc: <synth-diy at dropmix.xs4all.nl>
Sent: Monday, October 29, 2001 7:17 AM
Subject: Re: [sdiy] Pratt-Reed Mechanisms


>
>   (key not triggering)
>
>   It is possible the gold-plate has worn off the contact edge of the
> J-wire, the buss bar, or both.  You can get a gold-contact restorative
> (usually sold in little 3ml jars or a 'pen'), but these can be pricey.
>
>   Unless you have a very good reason to dismount the J-wire PC board from
> the keyframe, I would not do it.  I took apart the key action for a
> Prophet-5 a while back to resolder about 30 J-wires, and while nothing got
> broken, I can say it is a very delicate affair.  See:
>
> http://www.oldcrows.net/~oldcrow/synth/sci/Image003.jpg
>
>   All of those little plastic PCB standoffs have to be carefully extracted
> from the steel frame without jarring the PCB assembly.  Note that all of
> the keys were removed to fit new bushings.  This also has to be don to
> gain access to the mounting hols of the standoffs.
>
> Crow
>
> /**/
>