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How to use a Volt Ohm Meter Part 1
By Gary | June 30, 2008
Here is a good video on how to use a volt ohm meter. He explains in one example how to test for continuity. (circuit has little or no resistance between two points)
This is very important when troubleshooting a circuit. One example is you might find " a short" which means the same thing as no resistance. And you may find it where you shouldn't find it. You will know this either by experience or by looking at a wiring diagram/schematic.
Let's say you know by looking at a circuit board that a capacitor is between the input jack and the first part of a circuit. Since a capacitor blocks DC but passes AC and you hear your meter's speaker or see zero ohms by placing you leads on each side of the capacitor. This could be a clue why your amp is not working correctly.
Watch this video, he will touch on the different parts of the meter and what it does.
At the end of the video he suggests getting a Fluke meter. I would definitely second this. Even know a cheapo from the hardware store will work in a tight situation.
Think of your repair gear like having good music equipment. Sure, you can show up at the recording date with a cheap guitar with bad keys and get it done. But you know if you have a quality guitar with good tuners, you will be able to concentrate on your recording, not your equipment.
 Fluke Style Meter Test Leads US $5.99 |
 FLUKE AC DC CURRENT CLAMP i410 i1010 ELECTRICAL METER US $122.50 |
 FLUKE 33 CURRENT TRUE RMS CLAMP ELECTRICAL METER FRANCE US $41.00 |
Topics: electronic equip. | 2 Comments »
November 2nd, 2008 at 9:59 pm
Hi Gary,
Really appreciated your site and videos. I’ve recently purchased a Fender Ultimate Chorus amp. You probably know they are tubeless. So anyway, it has the wrong on/off switch in it. What is in there is a switch with three mail connectors. (The original, which I now have, is a DPST rocker switch with four male connectors)
I have no idea where the wiring should go now, and Fender does not give wiring instruction on their website. Was wondering you could help me?
Thanks,
Alan
November 3rd, 2008 at 9:15 pm
Hello,
I’ll try to look at a schematic tomorrow unless you already have one. Usually you can figure it out with a schematic if you know how to use an ohm meter and trace the wires back. Also you have to be able to know how the switch is working.
It would have been nice if the tech that took the proper switch out would have marked on the chasis what wires goes where.
It would be nice to have a variac for this job.
Talk soon,
Gary