HP71B PCB interconnection strip


I have just got around to testing a 71B I have had for a while and it hissed when I put the batteries in it.
I pulled it apart and the flexible connector between the 2 PCBs was badly corroded.
Does anyone have any ways of replacing the flexible interconnect or building a new one?




Hi Tony,

Sure. If you refer to this particular strip:

The possible repair has been addressed in this particular thread.

and a possible repair option could include soldering:

with more details on the procedure here.

Best regards from France.


Edited: 4 May 2009, 5:04 p.m.


Hi Etienne,

Thank you for the very detailed reply. This definitely looks possible, however I prefer to repair in a way that keeps the same functionality and operation, so will try to avoid soldering for the moment.

I was thinking about maybe getting some very fine gold wire (maybe from a jeweller) and setting up a row of pins to get the right spacing and winding the wire backwards and forwards to get the array of wires, then using something like adhesive tape to hold it in place, trim the ends to remove the short circuits, and then replace the original zebra strip with that. How to stop the tape from sticking to the holder is something I have not worked out yet.

Just had another thought that maybe I could wind the wire around the flexible strip and cut along it to form a set of wire segments.

I am assuming that the zebra strip used for LCDs are of too high a resistance to work correctly as a substitute, but I was wondering if anyone had tried that already?



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