82120A assembly questions


several months ago, i disassembled an 82120A pack with the intent to
replace the cells. naturally, i didn't get back to this project until
after the snow flew, and now can't recall exactly what came from where.
seems there are some extra parts.

i've soldered the new cells in series, and know which end to attach to
the circuit board. this assembly seems to only fit one way into the
case, so no problems there. the extra parts consist of a curved plastic
board about the length and height of the case, and two metal V-shaped
springs. my questions are: where do the board and springs fit in
relation to the batteries? are all the batteries supposed to make
contact with the 41 coppery contacts? (i only have the N-cell holder to
compare, and note that each cell is individually sprung). the soldered
battery assembly seems like it may be too stiff to make good even
contact against the 41. comments, suggestions, and especially pictures would be much appreciated.





The plastic strip fits between the case and the back of the battery string. If you used smaller batteries than the originals you may need to use a fatter strip to take up the space.

The spring clips connect to the outside two cells and are where the calculator battery contacts touch. The inner two cells do not use them. Look carefully in the holder and you will notice little "pockets" in front of each cell position on one half of the case. The curved part of the spring goes in the pocket.


thank you both for the quick responses. with your help i have ressembled the pack, and it is recharging just fine. i did use the smaller NiMH cells, and they are a bit loose. i assume this means possible premature failure of the soldered tabs, but i'm too jazzed at the moment to take it apart again to rectify that.

next project is to rebuild the 88014 pack for my disk drive.

thanks again.



> next project is to rebuild the 88014 pack for my disk drive.

This is easy. The suitable cell pack (not the drawer itself;-) can be ordered from Panasonic and other vendors.


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