Listen to Ian, he knows a heck lot more than I do!
Hehe.
I haven't read any of the books that Tighe linked, but I'm sure they will help. The manual for the multimeter will tell you how to use the multimeter itself, but it won't teach you how to apply it. Much like the manual that came with your car will teach you how to operate the car itself, but won't teach you how to drive.
The multimeter is actually very simple - while it looks intimidating with all those settings, it's very straightforward. You need to set the knob to what you are looking to measure - there are positions for AC and DC volts. On a manual ranging meter, like Tighe's, you also have to select what voltage range you're looking for. On the 20v setting, which is probably what you'll use the most, you can measure from 0 to 20v.
The meter simply displays the voltage difference between the two probes. The black probe traditionally goes to the DC ground, and the red one goes to the voltage you want to measure. But it can be used a lot of other ways too. If you want to measure the voltage drop of the harness, you'd set the knob to the 2v setting, put one probe on the power supply ground, and one probe on the ground trace on the game board, and you'll see the difference between them (it'll be small, should be less than a volt).
Measuring resistance works the same way.
ArcRevival said:
Just a note, there is an un-used edge on the board near the top that looks like where you would slip an Atari style edge connector on, you can measure voltages there too. I don't remember where each voltage is on it but if you walk along it with your meter it should be obvious. It's easier than measuring at chips.
I don't remember that being on the four board set.
While walking along an unknown connector with your meter will eventually net you a reading, remember that TTL signal levels also measure as about 5v, and unless you have the actual power rail, it won't be accurate. Also, if you hit video or something, you'll get a weird, low reading. It's better to learn to recognise the power and ground planes on the board and measure at something directly connected there. You want to *know* that you're supposed to be getting five volts at the location you're testing.
Checking pins of a chip is kind of hard - but if you remember which pins of a ROM are ground and 5v, it'll make identifying the power and ground planes a lot easier.
-Ian