Hi welcome to the Eev blog an Electronics Engineering Video blog of interest to anyone involved in electronics design. I'm your host Dave Jones Hi I Just finished shooting a tear down of this new Agilant u1272a multimeter and I was pretty darn impressed with it I have to post it as a separate review but at the end of it I put it back together and it started to play up intermittently and I've caught it on camera with which I'll show just here I I've been playing with it for the last 10 minutes and I cannot seem to to actually repeat it. It seems to work just fine now, but it did actually play up and I'm not sure if it's something I did in the tear down and if it is, well, quite frankly it's crap because I've never had a meter fail like that. especially weird intermittent software type stuff after a tear down.

so Agilant need to take a I reckon they need to take a look at this and in investigate and let me know what's wrong because it's just crazy. something weird is happening. So here's the footage and I'll post a tear down as a separate tear down I Probably won't mention this in the tear down because it's a dedicated thing. I Just wanted to put this video up quick to show you this Fo mode and if you've got the same meter, see if you can actually, uh, reproduce it just by switching it off and on.

Uh, basically, that's pretty much all I was doing. Um, so yeah, give it a go. Here's the footage: H Something very strange is going on here. I It seemed to work a couple of times and I switched off and it was doing something weird.

It's now overloading. It's saying like overloaded th000 volts. There's the high voltage warning indicator and it's doing something weird. I've got those.

Let's disconnect the probes and look. I've got no probes connected to that at all and it's showing. Look on the AC Vol And no, it's now down to 2. Vols Okay, it's going down, but it really is.

Look at that. it's 300 Vol 230 volts. What high voltage? What? what? What's going on here? Some weird stuff happening that's crazy. Let's plug the probes in Something really wrong here.

and let's uh, let's short out the probes and short out the probes and we're getting oh yeah, no problems. 27 volts. Yeah, right. What is going on Strange.

Let's turn it to molts. No, it doesn't like that. Let's turn it to Volts. There we go, Volts.

Well, it's not going down to uh, zero. but um, there's you know? that's all right. Let's go over to Ohms. Hey, look at that.

Something weirds going on here. This thing has crapped itself crazy. Short out the probes. Ohms.

Yep. something. something's gone wrong in the tear down. Would you believe it? Ah, what a loser.

Well, it's getting the temperature right. I Think it's probably about 18.5 de here in the lab. but let's switch this off and see if it resets itself. No look, it's stuck there on those on those digits.

I sh out the input and it's just stuck stuck on that. What did I kill it with ESD Or something? That's actually part of my standard tear down test is not to wear an antistatic wrist strap. Um, when tearing these things down, it's all part of the uh robustness test. and I I have no idea if that's the problem or not.

but I've it looks like I've done. hey, no. hang on. It's decided to come good again.

There you go. It's decided to work all of a sudden. Short that out. Go to Ohms.

There you go. it's working again. Not a problem. Let's uh.

there you go. It's decided. it's decided to work again. Crazy? Yeah, no problem at all.

Mill Volts Volts. Yeah, that looks all okay to me. that looks fine, but it's done something weird and it's looks like it seems to work most times. I Switch it off and on, but occasionally it just locks up and does something weird.

A lot of garbage. Let's try it again. Try it. The uh.

low impedance mode. 3 volts. Yeah, so much for low impedance mode. Getting rid of ghost voltage.

Look at that buzzer working and so is the Uh visual audio alert indicator. There we go. That's Volts mode. After about five, uh, switch on.

it just goes crazy. It seems to be a bit random. Let's try it again. I'll switch it off and switch it on.

There you go. It's doing wacky stuff. again. Switch it off.

Switch it on. now. it seems to have gone permanently into wacky mode. There we go.

It works. again. Crazy. and it's actually spot on.

There's no problem with the spec at all. Uh, so it. it appears to work. When it actually works it, it seems to work.

but I actually haven't been able to make it. Do it for the last 5 minutes. It's crazy. but um, it certainly is.

You saw it. it was locking up and doing something weird. So if you've got the same meter out there, try it and see if you can actually get it to lock up like that somehow. I I I Don't know.

I Just can't believe it's something I did in the tear down.