Multimeter (Fluke)
The fuses on these are blown quite frequently from misuse. If you have one with a blown fuse, you will waste a lot of time.
If you put more than 1A of current through the low current input (rather than
20A input) of the multimeter, you will blow a fuse. This usually happens when
you use the meter to measure current in parallel across a resistor instead of in
series, but if you have a short in your circuit (if things are hooked up wrong),
it can easily happen even if your meter is hooked up right.
To check if a multimeter current setting is bad,