I have a Williams Pharaoh that I recently aquired. When I received it, the remote battery holder was already looking acid damaged and the batteries were dead. I replaced the holder and the new batteries died in a few days. Anyhow, the batteries die very quickly. I'd appreciate advice on troubleshooting this issue. I already replaced the blocking diode thinking that would be the easy fix.
Thanks!
JR
The blocking diode D17 is to prevent batteries from being charged.
If you put in fresh batteries and have the machine "OFF" try measuring voltage on IC 18 the large pia 6820/21 pin 20 Vcc and pin 1 gnd. You should have no voltage. You should have no voltage on any of the IC(s) except IC 19 the 5101cmos ram chip that holds the bookkeeping info. If you do have voltage on other ICs something is bad causing the entire board to be getting voltage which would quickly drain the batteries.
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Denver, CO