I have a Craftsman DMM model 82357 that I bought in the late '90s or early 2000's. I believe it's equivalent to one of the WENS 20TRMS units. I like the unit but recently I noticed the resistance values are incorrect. My best guess as to why is last year the probe touched a ground plane while doing a continuity test with the board powered. The GFI receptacle kicked off so I assumed no damage to anything. I generally look at continuity rather than absolute resistance so perhaps something else caused the issue.
In any case, I opened the case and overall I don't see anything clearly burnt. I did locate a chip with the label "14053B PMG044" (apparently an analog multiplexer/demultiplexer based on the datasheet) that appears to have gotten hot at the pins as the solder has a reworked look.
It looks like I can get them fairly easily so I could just replace it and see what happens, but I was curious if anyone has suggestions on this model or repaired a similar type of DMM issue? Yes, I can replace it with a cheapo Uni-T or a nice Fluke but I'd like to see if this one can be resurrected for fun and maybe extend its life.
In any case, I opened the case and overall I don't see anything clearly burnt. I did locate a chip with the label "14053B PMG044" (apparently an analog multiplexer/demultiplexer based on the datasheet) that appears to have gotten hot at the pins as the solder has a reworked look.
It looks like I can get them fairly easily so I could just replace it and see what happens, but I was curious if anyone has suggestions on this model or repaired a similar type of DMM issue? Yes, I can replace it with a cheapo Uni-T or a nice Fluke but I'd like to see if this one can be resurrected for fun and maybe extend its life.
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