I would like a video on how to use an analog multimeter. - Page 1
Forum section: electronics / general

author: Lawsen
author_rank: Frequent Contributor
timestamp: November 10, 2011, 10:24:21 pm
content: I thought about making a video about this subject. I would like Dave Jones to make a video on reading the various scales on the Radio Shack Micronta analog multimeter. I own that same analog multimeter, but few people use an analog multimeter. I have a Radio Shack Micronta and Philips PM2505 analog multimeter. Some Radio Shack project kits have analog meter, too.

author: Psi
author_rank: Super Contributor
timestamp: November 10, 2011, 10:47:30 pm
content: I dunno about that one but they're normally pretty straight forward to use. Just;- Move the range switch to the feature&range you want- Connect the meter to your circuit- Read the value from the meter using the needle scale text that corresponds to the range/setting your using.Unlike digital meters the Ohms function is divided into multiple ranges, so you start on x1 range and move to more sensitive ranges in order (x10 x100 x1k etc) until you get a reading.Really, the only situation that requires some knowledge is testing transistors and figuring out their pins.

author: IanB
author_rank: Super Contributor
timestamp: November 10, 2011, 11:02:54 pm
content: Also the resistance scales usually have a manual adjust wheel for setting the zero. You short the probes, adjust the needle to zero, and then make your resistance measurement.

author: IanB
author_rank: Super Contributor
timestamp: November 10, 2011, 11:05:20 pm
content: Analog meters also read most accurately in the upper half/third of the scale, so you should carefully pick the best range to put the pointer in that region. Good meters also have a mirror backed scale; when you take a reading you should use one eye and line the pointer up carefully against the mirror.

author: Psi
author_rank: Super Contributor
timestamp: November 10, 2011, 11:09:20 pm
content: Also some have a knob that reverses the polarity on ohms range. (might work on other ranges too)It saves you from having to keep swaping the probes around manually when testing transistors.

author: ablacon64
author_rank: Frequent Contributor
timestamp: November 11, 2011, 12:21:12 am
content: My main job is diagnostic and fix notebook motherboards and I prefer to use the analog multimeter because they're more accurate, specially when diagnosing mosfets and regular transistors.You have to take care with the resistance scale, one minor error (IE, plug the ac adaptar and forget to change the scale) may damage the multimeter, specially the 1X and 10X scale, that we use mostly.

author: vk6zgo
author_rank: Super Contributor
timestamp: November 11, 2011, 12:50:47 am
content: One other thing about analog meters (VOMs),is that most of them reverse the polarity on the test leads when on resistance ranges.In other words,in resistance ranges,the meter becomes a voltage source with positive on the black lead,& negative on the red.This is done to simplify the internal switching,& only really matters when you are looking at semiconductor junctions.If you have other meters,it is easy to determine if this happens on your analog meter,by checking the polarity of the voltage present on the leads,or by testing a known polarity diode.VK6ZGO