Allen MDS45 Lamps

[sandstone42]

We have an Allen MDS46 (variant of MDS45) on which both the pedal and music rack lamps are out. We tested the voltage at the plug for the music rack lamp and there is no power. Is there a user serviceable fuse or current limiter that could be replaced without having to have a service call?

[jbird604]

The pedal lamp is of course a simple little screw-in light bulb that you can get from many sources, such as a hardware store or even a discount store. It is plugged into a switched outlet on the AC distribution box, so just check to make sure it hasn't gotten unplugged for some reason. If you need a new bulb, you can get one that has an LED inside instead of a filament, which is a good upgrade.

The music desk light on early MDS models is a button-start fluorescent tube, and it is plugged into a NON-SWITCHED outlet on the AC distribution box. Check to make sure it hasn't been unplugged, or plugged into a switched outlet by mistake. Note that it does NOT come on automatically when the organ is switched on, nor does it go off when the organ is turned off. So you must manually turn it off and on with the push-button on the end. If someone unplugged the organ console while the music desk light is still on, it will go off, and then the next time you try to start it, it will be "out of sync" and you will have to try twice, with two button presses in a row (holding it in for a few seconds each time). Forgive me for talking about that if you already know this and have tried that.

Otherwise, try plugging it into an extension cord instead of into the Allen distribution box, just to see if it works that way. If not, then the trouble is with the light and not the Allen AC box. Once you know for sure which unit is bad, you'll know how to proceed. If the AC box is bad, someone who is knowledgeable about electrical work might open it up and look for some obvious problem. But there aren't any fuses or circuit breakers in there that I know of.

If the light is bad, it could just be the fluorescent tube,which is easy enough to change. There is also one of those little round "starter" things in there that might need to be replaced, or it may have come loose from its socket. (I could be wrong about that, there may not be one of those in these organs.)

Finally, since this is an MDS organ, if it happens to be a late production model, it may have very peculiar music desk light system that runs off 12 volts DC. You can distinguish it from the other by the presence of a small toggle switch instead of the push-button. If so, you may want to replace it with some kind of inexpensive and compact LED strip that will fit into the cavity in the music desk, and run the power cord down to the floor of the console where you can plug it into the AC box or come up with some other solution for power the strip.

I have seen several of these DC-driven lights go out, as they depend on a complicated circuit that converts the 12 volts DC back to 120 volts AC to drive a miniature fluorescent tube. Nice idea, I guess, though I don't know what they were thinking. Nowadays replacing that entire mess with an LED strip is a piece of cake and much cheaper than replacing the converter circuit or the 12 volt supply in the organ floor, if that is what has actually failed.