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--></style><title>How I spent my week (Polymoog
restoration-long)</title></head><body>
<div><font color="#000000">Thought I'd share something to illustrate
an issue that kind of bugs me.</font></div>
<div><font color="#000000"><br></font></div>
<div><font color="#000000">Maybe I've been in my hole too long or are
just plain obsessive, but when I hear of folks who say they're going
to restore a synth, yet have never seen what one should be like
originally or have much experience with the particular model, it can
kinda irk me.</font></div>
<div><font color="#000000">For me, the term "restoration" is
often used like the word "Mint" on Ebay.</font></div>
<div><font color="#000000"><br></font></div>
<div><font color="#000000">Time and time again I hear of well meaning,
but naive "techs" who say they've restored a unit and didn't
do anything close to what was really needed for reliability, stability
or to return to a stock, original condition. Often they don't know
what's missing, broken or substituted because they've only seen a
handful of the synths at best.</font></div>
<div><font color="#000000">They concentrate on replacing caps, but
ignore old trimmers and cracked soldering and other huge issues. Many
"upgrade" their synths with "much better opamps"
or other mods, but don't do the base work required to support
improvements to begin with.</font></div>
<div><font color="#000000">Many believe that all of a synth's problems
can be understood via the schematics and don't take into account, the
real world and what time does to electronics.</font></div>
<div><font color="#000000">These situations, along with some bizarre
assumption by sooo many that when there's a problem, it MUST be an
IC.... I offer what I've done, so far, to a Polymoog over the
past week. Very little of the time has been spent on component level
repairs, though there may be more work necessary regarding
this.</font></div>
<div><font color="#000000">Keep in mind- I've yet to open the
schematics or power it up!<br>
There's no use testing a synth that has obvious visual problems and
can cause worse damage, imho.</font></div>
<div><font color="#000000">All CMOS IC's, previously in sockets
(except 4046's) were tested on an IC tester and several were bad and
replaced. What's left, I will soon discover.</font></div>
<div><font color="#000000"><br>
This unit has been to four, count 'em, four LA techs.<br>
Each one took a stab at it and failed.<br>
Two said it couldn't be repaired, one said that he couldn't get parts
and one tried to convince the owner it was normal and "working
fine for a keyboard of its age."</font></div>
<div><font color="#000000">The owner even brought this tech an example
of how it should sound like, by letting the tech listen to some Gary
Numan! :)</font></div>
<div><font color="#000000">Several of the dividers were replaced with
a cmos based pcb (you've probably seen this mod offered online
before).</font></div>
<div><font color="#000000">Wires were strained, rust all around, dirt,
bad soldering, loose everywhere, substituted or missing screws, subbed
components, klugey repairs... on and on.</font></div>
<div><font color="#000000">A real mess.</font></div>
<div><font color="#000000"><br></font></div>
<div><font color="#000000"><br></font></div>
<div><font color="#000000"><br></font></div>
<div><font color="#000000">The owner said he wants it as nice as
possible and that costs are not an issue, but time is. With that in
mind..... ;-)<br>
<br>
Jerry Casale/Devo Polymoog Keyboard, Serial #xxxx<br>
<br>
<br>
<b>Back panel-<br>
</b>All jack hardware replaced<br>
Jacks cleaned/polished<br>
S-trig jack replaced<br>
AC inlet replaced<br>
Resoldered fuse holder wiring<br>
Fused replaced<br>
Many screws replaced<br>
Tightened all fasteners<br>
Cleaned and detailed<br>
<br>
<b>Main structure-<br>
</b>Epoxied stripped keyboard stand mounts<br>
Replaced missing screws<br>
Tightened all fasteners<br>
Cleaned and detailed<br>
<br>
<b>Front panel and PCBs-<br>
</b>Resoldered boards<br>
Repainted silver lettering/legends, etc.<br>
Cleaned all sliders, switches and connectors<br>
Cleaned and resurfaced ribbon controller to new condition<br>
Rethreaded support mounts and replaced screws<br>
Replaced misc screws<br>
Tightened all fasteners<br>
Cleaned and detailed<br>
Board washed<br>
<br>
<b>Main divider board-<br>
</b>Replaced (8) eight "mod boards" substituted for
unavailable MM5823 divider IC's with original, new IC's from our
stock. Board returned to original.<br>
IC sockets eliminated<br>
Connectors cleaned<br>
All PCB connections resoldered and defluxed<br>
Board washed<br>
<br>
<b>Top octave generator boards (2)-<br>
</b>IC sockets eliminated<br>
Connectors cleaned<br>
All PCB connections resoldered and defluxed<br>
Edge card fingers hand polished and cleaned<br>
Board washed<br>
<br>
<b>Power supply-<br>
</b>Replaced all electrolytic caps with new, higher voltage types<br>
Replaced transformer connections with new, gold plated mating
connectors<br>
Replaced 25 year old, single turn adjustment trimmers with new, 25
turn cermet trimmers</font></div>
<div><font color="#000000">IC sockets eliminated<br>
All PCB connections resoldered and defluxed<br>
Replaced poorly attempted transistor wiring with teflon coated, silver
plated copper wire and heatshrink (mil-spec/unmeltable)<br>
Resurfaced heat sink surface flat and applied new heatsink grease<br>
Board washed<br>
<br>
<b>Main voice card carrier boards (3)-<br>
</b>All PCB connections resoldered and defluxed (2,626
connections!)<br>
IC sockets eliminated<br>
Main amp IC's replaced with new<br>
Connectors cleaned<br>
Edge card fingers detarnished<br>
Boards washed<br>
<br>
<b>Voice cards (71 voice boards, 3 driver boards, 1 bypass board)-<br>
</b>All cards inspected and resoldered as needed<br>
Edge card fingers hand polished and cleaned<br>
IC sockets eliminated<br>
Electrolytic cap replaced on bypass board<br>
<br>
<b>Main PCB's (3)-<br>
</b>IC sockets eliminated<br>
Electrolytic caps replaced<br>
Many trimmers replaced with multiturn cermet types<br>
Connectors cleaned<br>
Boards washed and defluxed<br>
Resoldered as needed<br>
IC sockets eliminated (except for uA726 ICs)<br>
Many IC's replaced- some were bad, some were substitutes<br>
<br>
<b>Keyboard-<br>
</b>All bushings replaced (71)<br>
All keys cleaned<br>
14 keys replaced (special weighted types)<br>
Spring tensions checked with gauge- 6 springs replaced<br>
New lube applied<br>
All screws replaced<br>
Key contacts cleaned and detarnished<br>
Connector wiring resoldered<br>
<br>
<br>
All solder used is Kester silver bearing solder<br>
<br>
Unit will be tested, any component level troubleshooting completed and
calibrated next week.</font></div>
<div><font color="#000000"><br></font></div>
<div><font color="#000000">Cost? I have no idea.</font></div>
<div><font color="#000000">What would YOU charge?? :)</font><br>
<font color="#000000"></font></div>
<div><br></div>
<x-sigsep><pre>--
</pre></x-sigsep>
<div>Regards,<br>
Kevin Lightner<br>
<br>
Myself: http://www.synthfool.com<br>
Service and sales: http://www.moogmusic.com/service.php<br>
Sales: http://www.cluboftheknobs.com</div>
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