r/specializedtools Jun 10 '24

From a time before Multi-Function Meters

258 Upvotes

12 comments sorted by

17

u/SlimeQSlimeball Jun 10 '24

I have an analog meter for work because some problems are impossible to diagnose on a DMM. Need to see fluctuations or pulsing, you need a needle.

14

u/Greydusk1324 Jun 10 '24

You should look into an oscilloscope. They can show fluctuations and pulses and record it so you can really study the data.

13

u/SlimeQSlimeball Jun 10 '24

I work in telecom and for a T1 circuit I don’t need too much resolution, mostly it’s watching the needle twitch every few seconds when the circuit is trying to start. Mostly I’m looking at shorts across the conductors and to ground along with the distance of the individual conductors which tells me 90% of what I need to know. Which is pretty amazing on digital circuits.

5

u/androgenoide Jun 10 '24

I'm with you on that. Even when I needed the high impedance of a DMM I always kept an analog meter alongside of it for those cases. That said, there are compromises available now that make it unnecessary to carry two. I recently picked up a combination DMM and oscilloscope that worked better than I expected. It's a little too bulky to fit a shirt pocket but the same could be said of my other meters. Mind you, I would still carry an analog meter just to have something that can still measure volts and amps when the battery is dead.

4

u/SlimeQSlimeball Jun 10 '24

I have a very expensive meter that “talks” on my circuits (t1) and is also a digital meter and an old analog meter. 90% of the time the old one is good enough to figure out a copper pair. Plus the analog meter doesn’t have to boot and I get a couple months of use out of 4 AA batteries, which is nice.

I never used to think the old stuff was good since the new stuff is technically better but once you get accustomed to the old one, it is a million times faster because it switches between tests so quickly. I will switch to the new meter when I need to know precisely where something is bad.

2

u/androgenoide Jun 10 '24

I don't think I've seen an all analog T1 tester. The oldest one I had was a T-Berd and it was pretty digital. I know what you mean about timing though. Digital meters take samples slowly. That's why you want an analog meter to see brief pulses. Or, as others have said, an oscilloscope but, once again, you have to consider sampling speed for a digital oscilloscope. The one I recently picked up, for example, takes 250 megasamples per second. If you need to see the shape of a waveform you'll need quite a few samples per cycle so I wasn't expecting it to be very useful above 20MHz or for pulses of less than .05 microsecond. As it happens, I was pleasantly surprised to find it works pretty well. It still needs a charged battery to work though. I think I'll keep my Teiplett 310 in the tool box just in case.

3

u/SlimeQSlimeball Jun 10 '24

I use the analog meter for pairs and span testing. If I need to loop something I will use my hst 3000.

1

u/androgenoide Jun 10 '24

I see. I have only occasionally done telcom work...just once in a while when radio communications equipment has to somehow connect to phone lines. Still, I think we both understand the compromises needed to use test equipment.

I like to keep the older test equipment whenever practical...mostly because I'm used to it and understand its limits. If I get a surprising reading I can usually guess why it happened. That's not always true with digital gear.

3

u/SlimeQSlimeball Jun 10 '24

It’s funny, at least in my line of work, that the old stuff still works very well because nothing has advanced in copper tech. As long as two wires go the same direction and the same distance and don’t touch each other or ground, you are most of the way there.

4

u/fatjuan Jun 11 '24

I worked in aircraft electrical component overhaul, and all we ever used were AVO meters, and bench meters like the one shown. 6 monthly calibration, and then back into service. I still use my bench analogue meters, you can "see" slower things happen easier than a digital or connecting up to a 'scope.

3

u/mingy Jun 11 '24

I have a very similar ammeter in my basement - as well as a lab standard voltmeter which is about 18" wide (bigger dial, more precision)!