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Joined: May 2002
Posts: 1,716
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How many still carry an analog meter in their meter arsenal?
With the sensitivity and false readings a DVM can give, I think it is a must to have something at your disposal (besides a solenoid type indicator) that can see the actual voltage.
Roger
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Joined: Dec 2001
Posts: 300
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I've always though that DVM's should have a high ohm shunt resistor across the leads to "bleed off" phantom voltages and readings from capacative or inductive effects of parallel wires.
A switch could be there so the resistor was optional and the leads could be shunted if something seemed odd. Then nobody would need an analog meter.
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Joined: Oct 2003
Posts: 147
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Apparently I have one in my arsenal. I found it the other day when I was going through the van looking for knock out fillers. I don't know if it still works.
I feel that it is necessary to have more than one different type of tester at your disposal. Where one tester does not produce reliable readings, a different one will produce an accurate reading. Also, it is my understanding that in extremely cold temperatures, a digital meter is almost useless.
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Joined: Aug 2001
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I still have several, including my trusty old Avo 8 and a Simpson 260.
In some electronics work you need to adjust for a null or a peak, and an analog movement makes that much easier than trying to keep up with the constantly changing digits of a DVM. The analog movement is also much easier to follow for voltages which are varying too quickly for a DVM to "keep up" (but not quick enough to require a 'scope).
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Joined: Oct 2001
Posts: 597
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While my day to day diagnostics are gathered through a older Greenlee DVC6 ![[Linked Image from 198.247.193.8]](http://198.247.193.8/wwwroot/greenlee/WallyTest/thumbnails/07540.JPG) I've always liked the "throw away" analog multimeter. Just about the cheapest I've found has come from Radio Shack. That way, if I drive over it, drop it, or (most likely ![[Linked Image]](https://www.electrical-contractor.net/ubb/biggrin.gif) ) forget to change the scale back from Ohms before contacting a live circuit, I'm not out much. I keep two on the truck. A modest input impedance d'Arsonval analog meter smoothes out the "jitter" of the step-wise digital world ![[Linked Image]](https://www.electrical-contractor.net/ubb/cool.gif)
Al Hildenbrand
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Joined: Dec 2003
Posts: 524
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... I had a Simpson,..gave it to my father when I found it was a pain to read,..then got me a DMM, now I have an "Archer" analog set from Radio Shack that I "built" myself,...don't use it much any more tho'...took out the batteries while storing it... Russ
.."if it ain't fixed,don't break it...call a Licensed Electrician"
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Joined: Jul 2003
Posts: 394
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I had to ring out a multi conductor flex cable the other day. One circuit was a flasher. Digital meter was next to usless, found it with an analog in a couple of seconds.
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Joined: Oct 2000
Posts: 2,722
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Use a variety of Low, Medium and High input Impedance Analog Voltage Meters + Multimeters, in conjunction to the DVMs and DMMs.
Also use my old Analog type "Amprobe" clamp-on Ammeter, in conjunction with the Digital counterparts.
The Analog display - with the sweeping "Needle" - makes a great visual aid when levels are fluctuating.
My most simple fix, as to tame peaks shown on a High input Impedance DVM is to connect my Wiggy in Parallel with the DVM's leads. Aligator clip the DVM's leads to the circuit, then place the Wiggy's leads in the same circuit. Dumps the Cap. charge safely, and no shunt Resistor is needed!
Scott35
Scott " 35 " Thompson Just Say NO To Green Eggs And Ham!
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Joined: Aug 2002
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Crash said: Also, it is my understanding that in extremely cold temperatures, a digital meter is almost useless. Yes, I've noticed that LCDs (liquid crystal displays) don't like cold weather. They turn purple. Used to have that happen a lot with a digital-tuning radio with L.C. display where it would get dark if I carried it around in cold weather. Once I got inside it would return to normal grey. I've got a little analog VOM that I picked up for $12 at a DIY shed a few months back. About the size of a packet of cigarettes, it needs a pen-light battery for use as an ohm-meter, but works fine as is when used as a voltmeter, which is OK for quick-n-dirty readings of light sockets or other current sources, etc.
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Joined: Aug 2001
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Don't forget that we can also have high-impedance analog meters, again used regularly in the past in radio/electronics work in the form of the VTVM (Vacuum Tube Volt Meter), or the more modern version with an FET (Field Effect Transistor) input. Scott, You'd probably appreciate an old lab-type DVM I have here. Built by the British Solartron company in the early 1970s, it's in a 19" rack cabinet which weighs a ton, and has inch-high Nixie tubes for the readout. Input impedance on the lowest range is over 2000 megohms, and it has built-in calibrators, 50Hz filters, variable-rate or one-shot sampling, maximum/minimum hold etc. I got it for just a few pounds, but it must have cost a fortune when new! ![[Linked Image]](https://www.electrical-contractor.net/ubb/smile.gif)
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Joined: September 2005
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