Anyone? I'm sure this has been done before on this unit or others like it.

here is a 10 pack of no name batteries for under $15 but individual seem to run $7-9.

link

In serial numbers starting with 28..... and 31.... I found dead CR 1/3N solder tab batteries. I opened a later serial number starting with 32... and found a button style CR 2430 solder point style battery that looked original. It reminded me of some solder tab CR 2032 3V I had bought for replacing the batteries in an original Nintendo NES cartridges for my nephew (try play Zelda with no saved game🙁 ) and I remembered your question.

These 2032 fit perfectly in the holes for battery placement on both the serial nuber 31... and 32... that I am working on and are working great.
The 2032 is a more common battery and should be easier to find than the CR1/3N with solder tabs. I had previously called several specialty battery stores and asked if the would weld tabs on to a battery and they all said they did not have the ability to do that.

this shows the microcomputer board with the battery removed

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and here is the 2032 in place

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Good luck. Don't blow up your battery.

Thank you Peter for your reply. My BM 5000 serial # starts with 29. I had it all open last year when I performed a recap/cleanup. Of all the many pics I took, not one pic of the battery area lol. I haven't gotten to this project yet as I have a tektronix 2236 oscilloscope taken all apart on my bench and on almost every shelf in the room. Dreading putting that thing back together. Good luck with all your electronic adventures. 

Thanks for the info, just replaced mine too.

Took me less then 15min.

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[Double Post]

Nice, - but do be careful when working on these CMOS-based things.
Antistatic work area and tools is a must.

Martin

Jea static can be a pain, since working on old commodore computers a few years back I always wear a wirts strap.