In older systems the system battery commonly takes two forms, one is a rechangable battery, usually a blue cylinder with three nicad cells and operates at 3.6 volts. There is the possibility that it works and just needs recharging, but likely it won't take a charge. The other form is a little rectangular battery, also three cells but not rechargable, and it is alkaline so 4.5 volts. It will generally be attached to the case with Velcro. Sometimes you can use either type on a system, you just change a jumper. If it is the non-rechargable type you can use any type of alkaline three cell battery, just take the connector off the old one. If you need to replace the rechargable type you can use just about any 3 cell battery of 1.2 volts per cell, or two alkaline cells at 1.7 volts per cell. You can get battery holders at Radio Shack.
If you're really lucky you might be able to find a manual for the unit.
Edited by Tyger, 28 January 2007 - 04:24 PM.