Mattel Optigan

Just kidding. I don't have any troubleshooting advice for an Optigan! I've actually never worked on one myself, but I've seen plenty come through the store. My coworker, Takeshi Kawana services the Optigan, but seemingly reluctantly. I don't think these are a pleasure to work on...

A little info about them. Optigans are the "poor man's Mellotron." They were sold by the Optigan company, which was really Mattel. The discs are clear and opaque. A simple optocoupler circuit is then modulated by the spinning disc. This is very old technology that goes way back. Early movie soundtracks were done this way. I have 1940s electronics manuals that cover this technology. Sound quality is poor compared to tape, but it makes changing sounds super easy and quick. Just take a disc out and put a new one in. But wait, that's not all! You can also flip the disc for reverse sounds and stack discs for layered sounds.

Most of the cool sounds are only in the left hand, push button section. The "melody" sounds played by the keyboard are typically just a default organ sound, but some of the discs contain interesting guitars and flutes and things. The machine itself is not worth much unless it has a large disc library.

These keyboards typically have issues. Warbling, irregular tempos, intermittent buttons and keys.