Measuring some low-value resistances with one of my DVMs produced weird results: dead shorts around 10 Ω.
- Test lead tips clean
- Wires firmly mounted in probes
- Banana plugs OK
- Short banana jumper across jacks reads 10+ Ω
Took the meter apart and what do we see? An ABC ceramic fuse in good old PCB clips:
Spinning the fuse dropped the resistance by a few ohms. Adding a minute drop of DeoxIT to each end, rotating the fuse to scrub it in, and wiping off the excess put the total resistance back around 0.2 Ω where it should be.