Vintage Synth Repair

On Sunday 23 March 2008 17:41, pigeonbreath wrote:
> Archive Sound promptly sent out key buffers for my benched Prophet 5,
> and I promptly put them in.  Then I found out they have a top and
> bottom, so I get to do it again (won't take very long).  Even without
> making sure they're all right-side up, the change in feel is
> phenomenal.  And, I got to tweak the keys so they're all even, etc.
>
> Meanwhile, I find that someone has earlier butchered some of the
> J-wires.  Specifically, some of the wires have been replaced with
> soldered-on replacements that look terrible and, in one case, the
> solder let go.
>
> What material is best for replacing the J-wires?  And is there a
> recommended technique for attaching them so they're mechanically
> robust (lead-tin solder is *not* mechanically robust)?
>
> Once again, thank you all.  Surprisingly, there seems to be nothing in
> the P5 repair manual regarding the keyboard.  I guess techs of the era
> were just expected to know their way around Pratt-Read keyboards.

I can't speak to that instrument specifically,  but there have been times when 
I've replaced those in some instruments and a small dab of silicone rubber 
stuff right where the end of the wire enters the board seems to help a bit 
with longevity.

I've never known solder to have a problem,  either, unless it wasn't done 
right in the first place.  The issue with those wasn't ever solder joints 
breaking (that's how they were _all_ attached at the factory!) but the 
flexing of the wire eventually breaking it.  The dab of silicone seems to 
spread the flexing out a bit over a length of the wire,  rather than having 
it all be at one point.

-- 
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space,  a critter that can
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