Triplett, Simpson, Weston, etc Analog Panel Meter Measurements

[@fullwaverecked]

Holy smokes! It finally clicked. I finally got some current flowing through my dim bulb. That is genius. Use the DMM for a safe power supply and boost the remainder up to full scale with the 6 volts. I recently acquired 14 vintage analog meters. It's a long story, but I felt so bad about the low price that I offered him more. Being the perfect gentleman, (he reminded me of yourself and UD) he refused. So I'm determined to make a vintage hardwood dashboard to display these meters, in all there glory. Thank you for the how to David. Cheers!

[@twincam825]

Thanks for passing on all this knowledge watch a lot of your videos and always learn a ton.

[@ElPasoTubeAmps]

Thank you for your kind remarks. I am pleased it helps which has always been my goal in posting videos. Seems nowadays much of this elemental knowledge gets overlooked but the way I see it, this is where the rubber-meets-the-road for builders that like to know how to reuse vintage equipment which may be of exceptional high quality all the way back to WWII instruments.

[@amateurism1]

Thank you! I was going to attempt to replace a panel meter in my tube tester and I'm very glad I saw this video before I started.

[@petekelly61]

I enjoyed your video. Thanks.

[@stevenking2980]

Nice video. Yes you made it easy to understand. Great job!

[@PelDaddy]

Thanks for the informative video. Subscribed.

[@stevenking2980]

Man I love meters, especially those old black stand alones!

[@billclouston]

Nice tip, Thanks

[@DoItYourselfMusician]

Thanks for all of the informative videos. I was curious what tools you are using to make holes and cutouts in your project enclosures.

[@ElPasoTubeAmps]

I have a nice set of Greenlee punches in different sizes. They are a little pricey but I have several of them well over 40 years.

[@hugeshows]

I have a sneaky feeling that the DMM doesn't sample resistance using pure DC, and the fact that meters have inductance is what tends to throw the readings off. Also, some meters have a bypass cap, and that would have obvious AC implications. I'd be curious to see what the sampling signal from that DMM looks like on your scope.

[@ElPasoTubeAmps]

That is a darn good idea. If the DMM is an AC ohm meter, like an ESR meter, then the inductance of the meter would surely cause it to have some problems. I will definitely test it. Thank you. I may not make a video but I will let you know what I find.

[@hugeshows]

ElPaso TubeAmps It's just a wild guess. My bet is that it wouldn't actually be AC (change polarity) but it could easily be pulsing DC or something sawtooth like which would act sort of like AC on a cap or coil.

[@fullwaverecked]

Great video! I noticed on the back of the second meter you showed us in the video (100 micro amp simpson), that there was a round yellowish passive component attached across the two terminals. What is that? I have a bunch of recently gifted vintage meters that also have various resistors attached to the backs of the meters. I've been scratching my head for a month. Thanks!

[@ElPasoTubeAmps]

If it has something connected across the terminals on the back of the meter is surely a shunt to re-scale the meter. You can make a 100 uA meter measure anything you want with a proper shunt. I am sure that is what you are seeing. Some meters have internal shunts that you can't see without taking the meter apart. To determine what the meter is or is shunted for, I connect a high ohm pot in series with a battery and then all in series with a current meter I trust and slowly lower the resistance of the pot and see what the trusted meter measures and what the unknown meter measures. I think I have another video on how to shunt meters.

[@fullwaverecked]

@@ElPasoTubeAmps yes, and after watching your other videos, I can finally test my meters with confidence and no damage. Thank you very much!

[@moodyga40]

love it

[@noonan1587]

First, I love your videos! Thank you for posting. I have a number of DC Volt Panel meters with no indication of what it takes to drive them full scale. Is it possible to use your technique in this case to establish resistance or current? Many thanks and looking forward to your next video!

[@ElPasoTubeAmps]

Noonan Hi Noonan - yes, this should work on any meter I can think of. Just make sure you start out with enough series resistance so as to not damage the meter. Some of the meters already have shunts inside them and, for example, the meter may have a 500 mA scale and indeed be set up for 500 mA and so on.

[@fullwaverecked]

Ohm's law is my friend, and sometimes my evil twin... ;)

[@swingarmer]

I have a lambda 71 regulated tube power supply. The 500v meter (looks to be a simpson type sticks at 350v then goes back to zero when adjusted down. Do you know a good resource to consult before I operate on it? Good video BTW. Thanks

[@ElPasoTubeAmps]

Mechanical issues in these beautiful old meters are difficult to work on and in most of my cases, the results are not good. They are as delicate as a watch movement so it is easy to make things worse. Sorry I don't have better news. Determine what movement it is, i.e., 1 mA full scale, 500 uA full scale, etc. it may be stamped on the meter in small letters and buy another one off Ebay. That is what I suggest.

[@swingarmer]

@@ElPasoTubeAmps Okay, Will do. Thanks