Roland Jupiter 4 Vintage Analog Synthesizer restoration project.. While opening up this lovely synth I immediately spotted this purple electrolytic (Matsushita) caps. These had to go, cause they intend to leak and damage the synthesizer.
While recapping I also measured every single new component I use as replacement (you never know..!). It was new to me, that even a new panasonic capacitor started to show signs of leakage.
Next thing I spotted was the leaky battery, which I replaced with a CR2032.
Here`s a picture from underneath. Don´t forget to remove the parts from the charging circuit !
I also cleaned keyboard, keyboard contacts, switches, potentiometer, sliders, pcb, case...
I installed the MIDI kit by CHD ELEKTROSERVIS. The MIDI jack was installed behind one of these manufacturer plates. Unfortunately I have no pictures for you.
Calibration was also performed on this beauty.
There are lethal voltage exposed in electronic devices. Unless you know what you are doing, don’t try this. If you following along, you doing so at your own risk.
I’m documenting repairs for my reference and yours.
I do synth restorations and repair with a specialty in vintage synthesizers, drum computer and other vintage gear, based in Düsseldorf, GER. Get in touch about your synth situation!