I have a bag of capacitors labeled "104." (I don't recall their origin; probably an old AliExpress order.) However, they all test, on both my multimeter (a UNI-T UT61E) and a little microcontroller-based tester, as between 50 and 65 nF. I have another (clearly different in both colour and shape) "104" cap from another source that does test at around 93 nF, which makes me believe that I am testing them properly. (I do short the leads for a moment before checking the value.) But perhaps I'm not; am I missing anything here?
In case it helps, here's a picture of the caps in question: the two brown ones on the left are the seemingly 56 nF caps (front and back), and the one on the right is the actually-100 nF cap.
If I am measuring the value right, are these caps damaged in some way or just mislabeled. If the latter, is this sort of mislabeling common when buying jellybean parts?
I no doubt bought these as decoupling caps for things like old 8-bit CPUs and their peripheral chips. What should I do with these?
- Use a pair of them at each decoupling location to get the seemingly-standard 0.1 μf decoupling value.
- Just use a single one because 50-60 nF will work fine? (They do seem effective at cleaning up, e.g. a 1 MHz waveforms when I check on my oscilloscope.)
- Not use them at all because they're too dodgy?