Repairing & restoring HP82002 - advice needed

[Paul Berger (Canada)]

I have repaired several of these and the majority of them it was due to a broken wire near the calculator end. I find the breaks using the continuity check on a DVM attaching one lead to the end of the wire inside the wall end and the connectint the other lead to a needle which I push through the insulation. I have not found a replacement for the connector at the calculator end and to be honest never really looked. What I did to repair wires broken near the calculator connector is cut the wires before the break, slice open the connector just below the wide top part, but not cut it off completely but leave it as a flap still connected at the end where the wires come in. Next I carve out a cavity inside to dig out the wires and the top of the connector pins. I then work the old wire out of the strain relief, and bring in the end of the good wire strip the wires and solder them to the top of the pins. Once that is done and I verify that all is well, I fill the cavity with epoxy and glue down the flap with contact cement.

If the break is further away or at the wall wart end it is much easier to repair, if I was to repair a break in the middle of the wire I would cut the broken wire at the break and insert a sort piece of wire to join the broken end and cover the spot with heat shrink.

I have only ever had one or two electronic component failures usually bad capacitors, but I have had at least one where the pass transistor in the charge current regulator failed. If the 5V capacitor is bad, you will see flickering in the display when running off of the 5V.

Paul.