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HP32E Repairing
11-14-2016, 03:10 PM
Post: #6
RE: HP32E Repairing
(11-13-2016 08:51 PM)ElectroDuende Wrote:  No, I'm afraid that all Spices that I had lately monitored on Ebay have finished too much expensive for me (even defective models). I'll keep on waiting...

[...]I have no idea if the power for the LED display comes from the DC-DC converter or directly from batteries... but I suppose it comes from the converter, as the bright is quite constant during all battery life (although I use NiMH in my HP34C, and they have quite a flat discharge curve).

Thanks for your reply.

Concerning the LED display, I was curious where it can be repaired.
Assuming the issue is a broken bond wire (as per Kees description), a new thin wire could be soldered to the pcb and then just bent to make contact with the led segment; a small drop of conductive paint would fix it.
Of course this would require a magnifying system.
You know that these led segments can be tested in the usual way with just a multi-meter set to diode testing (I tested my LED display in this way using a Protek 505 which presents 2.9V in open connection).

Meanwhile I found the answer for my LED display power supply question. As you said, it is regulated from the DC-DC converter (Kees has published power supply schematics here).

Jose Mesquita member

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Messages In This Thread
HP32E Repairing - ElectroDuende - 10-11-2015, 11:03 PM
RE: HP32E Repairing - ElectroDuende - 10-12-2015, 02:00 AM
RE: HP32E Repairing - Harald - 10-12-2015, 07:24 AM
RE: HP32E Repairing - jebem - 11-10-2016, 02:18 PM
RE: HP32E Repairing - ElectroDuende - 11-13-2016, 08:51 PM
RE: HP32E Repairing - jebem - 11-14-2016 03:10 PM
RE: HP32E Repairing - ElectroDuende - 11-14-2016, 09:50 PM

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