If you purchased your Altair-Duino Experimenter kit prior to October 2024, it's highly likely that the Processor Technology Music System does not work.  This is due to two traces missing from the small expansion board.  This is an easy fix.

First, make sure you have the Altair-Duno Experimenter (not the previous Standard version, or the Pro version).  The rear panel of the Experimenter looks like this:

Before disassembling your Altair-Duino Experimenter, try out the Music System to verify it's not working.  If it's not working, proceed.  You will need to add two jumpers on the rear of the small expansion board in these locations:

I used leads I cut from a resistor:

After installing the jumpers, you can reassemble your Altair-Duino Experimenter and use the Processor Technology Music System.