(Topic ID: 134818)

System 7 draining batteries

By GoodToBeDad

8 years ago

Topic Stats


Linked Games

#1 8 years ago

I've replaced the blocking diode, but my BK is still draining batteries when the game is off. Any other ideas where I should look? Thanks.

#3 8 years ago

The only component causing this would be the diode the stops the batteries from trying to run the entire board or the ram chip The diode that blocks the batteries from charging has nothing to do with dying batteries.(just exploding batteries) Measure for voltage on both sides of the blocking diode, this will tell you if there is leakage getting past the diode somehow, If no voltage I would change your Ram chip

#4 8 years ago

Assuming your blocking diode is good (take a reading on each side of it).... What is the imprint on your 5101. Some AMI branded 5101s Williams used during system 7 era consume excessive amounts of current.

#5 8 years ago


I have a CM8104P-1 in place of the 5101. It's supposed to be a good replacement for the 5101, but I just put a new one in and the batteries are still draining. I ordered a 5101 today. Hopefully, that will fix it.

#6 8 years ago

2101's are also a pin for pin replacement,,,, but will eat your batteries like Skittles.

Stick with 5101, or better yet, get an NVram if your already dealing with a socket and get those batteries into a flashlight instead.

#7 8 years ago

CM8104P-1 is an interesting part number. That must be a soviet clone based on the prefix. CM601P is a valid cold war era 6800 CPU replacement. I can't find a data sheet, but some posts i found make it sound like it is a 2101.

#8 8 years ago

Rare RAM chip - Produced in Bulgaria, in Pravetz factory where Pravetz-8 and Pravetz-16 (Apple II and IBM PC clones) were made during 1980s

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