Proceed CD Library

I am just afraid if I do not find the answer a piece of audio history will fall by the wayside, let's not give up.
Thank you everyone!!

@tonyaudio
Can you provide some picture of the battery compartment?
What you need is a 4.8V battery pack connect or clip to the battery compartment + and - terminal to make it work or see if the Communicator (the controller) still in working condition.
If you got 4 of those 1/2C rechargeable NiCad battery on hand, add some conductive spacer to make it to correct length.

That sounds like it would work but what kind of a conductive spacer can I make or buy that you think would work best? I probably need about 3/4" in length to fill the gap, width is perfect. I am connecting them in series not in parallel so as you say that would give me 4.8 Volts.

My suggestion is cut a piece of 1" dia wood to 1/2"-5/8" length, drill and insert a 3/16" dia x 3/4" copper rod in the center.

Another option just for testing purposes would be a DC voltage power supply that is adjustable.
We use them at work, that way you could set to 4.85vdc and clip to the posts and see if it at least works.