The bulb you want is a GE Lighting 48707 40T10/RVLCD1 Tubular Bulb. For those who want to know more about this bulb, here’s the tech specs.

The best way to replace those red tabs is to simply buy a red permanent Sharpie pen and color over the appropriate metronome window. It works fine, and shouldn’t rub off. If you desire maximum redness, try rubbing it on both sides of the disc.

Attached to each amplifier is a little trimpot for adjusting the chord/keyboard volumes. On most Optigans, these trimpots can be accessed by the little holes on the back of the unit. If you still can’t get much sound out of an amp, or the sound is particularly distorted, the the amp has gone bad and [...]

Basically, you’re going to have to face the fact that the Optigan is inherently a very buzzy, noisy machine. Unless you want to completely replace the grounding and amplification system, your only hope is to try to minimize the buzz and maybe notch it out with a multi-band EQ or some noise reduction DSP. The [...]

Probably not. Mattel patented a better drive system for the Optigan, but you’d have to build the thing up from scratch in order to implement it. It’s based on a belt driven, electronically controlled system as opposed to an electro-mechanical system. The Chilton Talentmaker and the Vako Orchestron both feature a more reliable direct-drive system.

Yes and no. From a musical standpoint, they’re very VERY wrong! But nothing is actually wrong with your Optigan. In order to fit enough stuff onto the discs, they had to cut corners a bit. There wasn’t enough room for A and E major, so they decided that they would take a C# dim chord [...]

Chances are, there’s a small divot cut into your idler wheel. As the wheel goes around, it makes a knocking noise every time the divot hits the drive shaft. This is fairly easy to fix. If you remove the idler wheel (that’s the black, hard rubber one) and fill the divot with super glue, you [...]

It’s largely a futile effort, because the scratchiness is mostly caused by actual scratches on the discs, but if you really want to clean them, DON’T use water! Go out and buy some film cleaning fluid from a camera store. Keep in mind even a mint Optigan disc sounds pretty bad right out of the [...]

Crosstalk! Learn to live with it! If you don’t have the test discs, the easiest way to hear the crosstalk is by pressing the top most key on the keyboard. Crosstalk changes with the weather, basically- the light detector is very sensitive to temperature and atmospheric changes. The result is that adjacent tracks on the [...]

Often this problem can be cleared up by pressing the keys quickly and repeatedly. If this doesn’t work, you might try getting inside the thing and cleaning any gunk that may have gotten in between the rubber contact strip and the metal contact plates. I’ve also had good luck by simply turning the rubber strip [...]