Really Odd Meterman 37XR Problem

[mdonald623]

Hello EEV blog forum, first time poster here, love the show!

Okay so I recently came into possession of a "broken" Meterman 37XR. I turned it on and found that it beeps and displays "ERR" as if the probe is plugged in the wrong position. I started messing around with it thinking maybe something conductive got down in the 10 amp or mA terminal and suddenly it decided to work. I checked it out and everything works great, awesome, $150 multimeter for free I thought. So later that day I went to show it to a friend and of course the error was back full force. It turns out this error likes to come and go so I started to think I'd never fix it and it was just a goner.

Well today I found something rather interesting. I took the back off the multimeter and I started probing around and I found nothing that really jumped out at me, though I really only know just enough to make speculations. However I found out entirely by accident that by breathing on the damn thing I could set off the error!! I probed the two terminals in between the mA range and blew on it and watched as the resistance dropped drastically! I really am in over my head here as I couldn't come up with a logical reason this would happen. Clearly this meter was designed to handle humid environments, so why can't mine?

I would be entirely open to sending it to Dave for inspection/repair if he is interested.

[PedroDaGr8]

Hello EEV blog forum, first time poster here, love the show!

Okay so I recently came into possession of a "broken" Meterman 37XR. I turned it on and found that it beeps and displays "ERR" as if the probe is plugged in the wrong position. I started messing around with it thinking maybe something conductive got down in the 10 amp or mA terminal and suddenly it decided to work. I checked it out and everything works great, awesome, $150 multimeter for free I thought. So later that day I went to show it to a friend and of course the error was back full force. It turns out this error likes to come and go so I started to think I'd never fix it and it was just a goner.

Well today I found something rather interesting. I took the back off the multimeter and I started probing around and I found nothing that really jumped out at me, though I really only know just enough to make speculations. However I found out entirely by accident that by breathing on the damn thing I could set off the error!! I probed the two terminals in between the mA range and blew on it and watched as the resistance dropped drastically! I really am in over my head here as I couldn't come up with a logical reason this would happen. Clearly this meter was designed to handle humid environments, so why can't mine?

I would be entirely open to sending it to Dave for inspection/repair if he is interested.

Sounds like a cracked/dry/damaged/old solder joint. Heat from your breath causes the metal to swell filling the small cracks, dropping the resistance. I would take your trusty soldering iron and just remelt everything down there and see if that doesn't fix it. The other option is a cracked/damaged trace which you would have to probe all of the traces and then jumper the damaged trace with a wire. My guess is this will be easily fixed, just keep your eye open for cracked joints or joints that are dull and not shiny (this latter only applies to lead containing solder, lead free always looks dull)

[mdonald623]

Alright I'll try that and report back later today, thanks.

[tautech]

I probed the two terminals in between the mA range and blew on it and watched as the resistance dropped drastically!

Use freeze spray and hot air gun to isolate problem area

[nickshortie]

I know this thread is almost 8 years old but I just had the same issue with an 37XR-A and was able to figure out the problem and thought I'd share.

The problem is the two Amp sockets which are split in half for plug detection. If the contacts are a little bent and touch each other the multimeter displays 'Err'

cheers!