Darian just finished up a pretty labor-intensive repair on this 1968 Farfisa Combo Compact Deluxe combo organ for the owner of Collingswood Music in New Jersey. It should be showing up for sale in the shop there soon! The deluxe features that it has compared to the regular Combo Compact are a 2-2/3 footage you can add in (called “Brilliance”) and a simple decay envelope called “Percussion” that can be applied to the bass, treble, or both and repeats on all held notes every time you press a key. It has a tube preamp and the reverb is tube-driven.
Something we see a lot of in organs of this era is evidence of attempted DIY repairs. It speaks to an interesting cultural shift, because 40-50 years ago, regular people were way more likely to open stuff up and try to fix them themselves. Unfortunately, we often find that they did a lot more harm than good, and this one was one of the worst– for unknown reasons, a lot of its main control board had actually been rewired in a completely nonsensical way. So it took a lot of time to trace the schematic, figure out where those all went and put them back where they belonged.
Service Tips: The photoresistor for the optically controlled “Percussion” envelope circuit was bad, and after trying several replacements, we found the one that worked best was the GL 5337, which has a stated light resistance of 30-50 kOhm and dark resistance of 3 MOhm. They are easy to find on Ebay.
Work Done: Replaced electrolytic capacitors in power supply, preamp, bass preamp, “C” oscillator and “D#” oscillator. Replaced a few other electrolytics throughout plus two film capacitors to fix “Sharp” filter board. Replaced 4 germanium transistors on “C” oscillator board. Cleaned key contacts & reconnected disconnected contacts, fixed broken key contact. Fixed 6 broken rocker switches, cleaned switch contacts. Rewired faulty and incorrect wiring. Replaced reverb/preamp tubes. Replaced photoresistor for “Percussion” envelope. Cleaned body and case of organ.