HP-71B, CMT-CR-128K memory module


Much to my surprise, I just read where the CMT 128K memory module for the HP-71B retains its memory when detached from the HP71B. I opened the memory module and found a very small (smaller than a dime) battery pack with no identifying marks. The voltage across the contacts was .883 volts. Can anyone help me identify this battery so I can get a new one. Thanks. John Pierce


It's undoubtedly a 3 volt lithium cell. It should have a part no. on the cell, but if not, any lithium cell that fits will work. Check the Digikey catalog. Be sure to get a cell with tabs for easy soldering without damaging the cell. And watch the polarity!


Thanks Roger, This is the first time I have been to Digikey's website. Very impressive. John Pierce

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