Vintage Synth Repair

SH-101 Fixed

Roland SH-101 Repair

So i had a really good friend give me two pretty beat up Roland SH-101 Red.


They have lots of missing parts, broken caps, missing benders and missing bottom bed trays. This looks like a nightmare to the normal eye, but to me it looks like a great time to fix something. Just like the Arp Axxe repair job i shot in an earlier blog post, i will show you what i have done to these keyboards to get them to function properly.

Note: If you are not a service tech or have not been around service techs for years (which is my case) DO NOT OPEN ELECTRONIC GEAR!! You could mess something up, or worse hurt yourself. I have been shocked a bunch and know how bad it can hurt. AC & DC voltages feel different and effect you different. If you don’t understand the location of those things on power supplies stay away. Also have witnessed boards get destroyed in one fallen screwdriver (for real just zap goodbye!). Ok had to say that.

My first step is to find the service manual, become familiar with the parts on the particular board, find where the power comes in, where the location of all elements are (CPU, VCO, VCF, VCA, ADSR, LFO,), check all the boards and what looks like a problem from first glance. Make Notes.

Shot below is trunk of car Day 1. The back one is almost complete, but the CEM3340 is gone (main voice), two sliders are dead, bender is broken and bottom tray is missing. Also found out no tune knob and the battery cover is gone. The second one is missing 6 keys and springs, missing both CEM3340 and IR3109 (FILTER!!), bottom tray is gone and the sequencer button board is missing 6 buttons and a push button. Again most people would have not even looked over this, but in a short 1/2 hour look over this is what i found.


Next Step is cleaning. Now I am pretty OCD so cleaning is no big deal to me. You have to know the proper things to clean boards with. Contact cleaner can help, but good old water and alcohol can do some wonders. Using a mix of both along side q-tips and a small fine toothbrush you clean carefully. This stuff is pushing 30+ years so the harder you are the more of a chance the trace will come up, or somethings will get ruined because of being careless. Take time when cleaning and let things dry on sunny days. if all of the moisture is not taken out of the board after cleaning and you power the unit on it will be destroyed. Trust that. Before and after board clean below.



So once the board is clean you order parts. That is as far as I have gotten. Come back for more information on my red Sh-101 project. They say the parts will be here Friday so the next update will come after the weekend.




Finished Axxe

The fixed j-wire:

The key holders which also have the spring attached below:

The hardest part is putting the springs back on the key holders:

Make sure you start with C key first. Follow the correct order:

I traced the keys out so it was done correctly:

All springs and holders attached:

Keys in order:

First key on:

All keys installed:

Back on the Axxe:

Arp Axxe Restore

More on the Arp Axxe fix. Solder the j-wires today, and added the bushings. New bushings look really good and i got the great deal online. Here are shots of the j-wire board, and bushing install. Here at the bench @ Switched On with a great iron, and some good tools. Thanks guys!

Below is the bag of j-wires.

Below is half of the bushing install.

Bag of lubed bushings.

Still Restoring Axxe

Working on the Arp still. Did my order for the j-wire and bushings. Here is a link of who i recommend.

I have been using a MIDI to CV box with Ableton and using the Axxe with the two oscillators from the Roland 100M. Sounds pretty sweet. 3 oscillator analog monster. Looking into a fourth VCO and still haven’t decided on which to get. There are a lot of eurorack modules for sale and it’s tough to figure out which one will be the best sound for the best value. That’s why reading about them is hard enough, but then you have to go to some demo of a person playing the module through other modules. This makes judgement hard to pass because of the other modules surrounding it and the quality of the recording by the author.

The DIY Midi to CV. I will link you to the maker here. (Thanks Ebay)

Arp Axxe Restoration