DER-EE DE5000 CAL failure (FIXED)

[Lorenzo_1]

My DE5000 LCR meter failed CAL repeatedly on Short setting, while passing CAL on Open setting. Had been working reliably for a couple of years and used frequently.  Battery change made no difference and meter failed CAL the same way at same time with both the standard TL-21 short leads and the TL-22 tweezer set, which made me suspect the meter itself.  Have always been careful to avoid testing possibly charged capacitors.

After some exploration, Short CAL came good by inserting copper wire directly into +/- terminal connectors, bypassing the leads/3-blade adapters. Turned out both TL-21 and TL-22 leads had simultaneous soldering/wiring faults. The TL-21 set failed because of bad solder joints and a broken wire at both the crocodile clip and on the PCB inside the 3-blade connector.  The TL-22 set failed from a broken wire on one of the two PCBs in the tweezers.   The tweezer set took a few attempts to repair because the wires are quite fine and inflexible. Found it necessary to desolder all four wires and two ground sheaths, cut them all the uniform length and resolder.  Refreshed solder joints on all the PCBs while I had them apart.  A bit fiddly, but worked fine in the end.

Thought this might be useful for others who use this meter.