The end of March was really quiet, so I guessed folks were focused on doing/paying their taxes, rather than getting their gear repaired. I came across a nice professional work-station and rack that were available due to a lab move, so went and grabbed them to update the shop. Nice eh!
This unit had been powered off for many years, and although it looked nice once dusted off, oxidization had done its worst on key contacts, made sliders crackly etc. The brass section was not working, and the pitch slider was broken. I could not find a source for sliders, and ended up grafting a metal shaft onto the pitch control. The sliders are of a closed and sealed type, but thankfully (and surprisingly to me) injecting switch cleaner into screw holes in the slider cases banished the crackles.
Investigating the brass issue revealed cracks in a circuit board from impact, with a poor repair attempt in the past. I wire jumpered all bad and suspect circuit board traces such that if the crack grew a little then it would still work. The final issue was key contacts, and in the end I had to remove the buss-bars in order to clean them which is a major strip-down effort. The contact springs were really bad and had to be repeatedly treated using isopropryl as a cleaner. The results are pretty good, but the only way to get it to 100% would be to find new springs. Customer just loves it!
I do not know why, but March saw a stream of Roland Juno-106’s. Voice module failures were a common failure item, and I spent a lot of time running modules through the acetone bath. The acetone bath method is not a cure all, as once a chip is damaged by the epoxy coating shorting it, then it is bad of course. The acetone strip method is a good preventative maintenance item though. I have been suggesting that customers look at services such as the synthspa as they say they will replace bad modules as part of their stripping process, and I cannot compete with that as I’m having to purchase reclaimed modules for repair.
One unit had been dropped which resulted in a lot of broken keys, and a distorted panel. Another unit suffered a broken pitch bend lever, and another the plastic push “spring” for VCO modulation (both of these parts are available from Sam at www.syntaur.com).
Loss of patches due to battery failure was seen on 2 units, so I’m recommending replacing the battery now even if the voltage is good. The bad side of this though is that the patch loading tool for the Juno-106 only does a patch at a time (no sysex load/dump capability), so you have to do the tedious patch edit and save for all 128 patches.
Two units were highly touch sensitive, and this was due to multiple bad sliders. One issue leading to this is oxidization due to a bad storage environment, another is the crumbling gasket Roland used falling into the slider. The cure is to remove, open and clean all sliders, remove old gasket material, and make a gasket from stiffened felt. While I have been in this area I have also been replacing intermittent patch etc. switches, and really they should all be done if one fails as dust getting into the switch is the culprit.
A final issue seen is with the bubble contact strips failing and giving intermittent keys. On the Juno I seem to be seeing other factors such as a liquid spill (on the Korg Poly6/61/MonoPoly they just plain fail).
All of this is leading me to making the standard service for the Juno-106 include front panel switch replacement, slider removal, open, clean, and lube, gasket removal and replacement, battery change, and optional module acetone strip. This is all labor intensive so not cheap, but it would get the keyboard running nicely again, and last another 20 years.