Hi, please excuse the crude D of this video I didn't have time to build it to scale or to paint it I Just found an interesting thing which goes way back to a video I done which I'll probably have to link in way back like in the first 30 videos or something like that. Check this out! I got my new 4k monitor which is the Ben QEW 3270 and watch this. There we go. Did it.

It's switched off and switch back on when I get up off my chair, hang on I'll do it again. There we go and then switches back on. It does it almost every time and I thought like I originally thought that this was something where it was like somes whiz-bang autosense, a power saving thing where it was sensing that I'm like sitting here and when I move it switches off I didn't think much about it and and you may have. you may be able to guess I don't know guess answers on the back of a postcard what the problem is here.

No, it's not some whiz-bang super technology inside this that's sensing that whether I'm sitting in front of it or not. if I put my headphones on, maybe we can't hear this, maybe are I'll try and mix in the audio see if we can hear it, but let me stand up. I'm not sure if that'll come through or not because it depends on the system, but I can hear a little click click click in here when I stand up and that's due to the static discharge of me standing up from the chair like if I stand up slowly. Ah, desk, it's gonna make a fool of it.

but I can feel I'm wearing kind of a little bit not stretch denim, but you know, kind of like a little bit stretchy jeans. They are a bit staticky and I can actually feel the static build up when I stand up on here. So when a stand up off the chair, it causes that impulse. and I've got a very interesting story back in that old video about how this caused Hey really troublesome bug back in the day in the lab at a company that I was working at and finally figured out that day getting off the chair was the problem and generating static and that was upsetting my long term experiment or whatever it was.

anyway. um, that's the problem. So this monitor is I've got another BenQ monitor here which is a 24-inch one exactly like they're not exactly the same model, but near enough and it doesn't do it at all. So there's some sort of static impulse which is obviously getting into the you know the audio system somehow.

I'm not sure how it's getting in, so that's why you may or may not hear that click. There you go. it's interesting it I don't know. the path that it's getting in is a via like the HDMI cable at the shield.

on the HDMI cable is the electric field that I'm generating, actually inducing some voltage in there, which is sort of like, you know, tripping, tripping this thing up and causing it to reset like that. But anyway, thought: I'd show you that it's really interesting and just to show you the difference here: I'm actually now sitting on a cardboard a 1:21 GW box and let's give it a go. There you go. doesn't cause the problem because the fabric on the chair combined with my jeans and probably you know it probably has like one nylon thread for every other thread just to make it a little bit stretch.

yeah is causing that's static and work my headphones back in. Yep, Confirmed. No more click in the headphones. So and and I can feel it as well.

I can feel that there's less like you've almost. basically no static build-up whereas I can physically feel that. You know, like your little hairs stand on your end and stuff like that, you can feel that static impulse. So there you go.

Interesting, Huh? I Never thought. I'd revisit that old video. but yeah, keeps coming up. Ok, so let's get a slight bit more scientific about this, Shall we? I Got a scope here.

Watch this ready. Hopefully it won't make a fool out of me. Tada Anzo impulse. Let me do it again.

I Want the damn screen to go off? I Come on, there's our impulse that's at. What's that? Ten nanoseconds per division there, so you know me. Hundred ish Meg Something like that. so near enough.

And that's what my original video was about. was that I originally was picking up because the scope probe is an antenna. If I actually disconnect this, we probably won't get any coupling because we don't have an antenna. There you go.

but you plug it in and go to antenna earth. Lead on it and no walkers straight in there like that. And no, it's not the the piezo ceramic effect in there, which is an entirely different lower frequency thing. This is a high frequency stand in pulse into the lead of the oscilloscopes coupling through the front end.

It gets all complex and through the like common mode interference and stuff like that. And it generates because static can generate tens of thousands of volts and generates an electric field around you. and that's way you know you can spark across and that's why it. Oh, there we go.

Just sitting down, did it. And that's why it can generate impulses like that in the scope. and obviously something's going into the system here on the shield of the mains. and or HDMI that's where it's sneaking in.

Perhaps that couldn't Yeah, that'd be my guess, but it could certainly be just going directly into the circuitry of the monitor. I Just don't know. maybe I can pull it a bit closer or something like that. So I'm going to even though it may not have the frequency range.

quiet. I'm gonna try some little ferrite clamps because I I'm just going to whack them on the HDMI and the mains cables to see if I can stop them actually getting into the monitor and causing whatever it is in their part. you know there's monitor to reset or maybe it locks up and it's got a watchdog timer or something like that. Takes a couple of T's two or three seconds to recover.

Kind of put one of these clamps on the HDMI cable and see if that's the issue. You know you could get maybe a better quality. HDMI Cable Some of them even have the ferrite clamps built in and stuff like that. I'll see if I can reproduce it because all I need is one failed result to prove that that doesn't fix it.

So I don't get back to you and check this. that feels like I'm generating a lot of static. A big packing bag and one of my one of my multimeters put that in and out. Wow! I can feel the hairs on the back of mine but I can't do anything so I can't trigger that.

so I'm not sure. nah, it's the magic chair I'm telling you. oh no, got it There You go, got it. So that had the that had the ferrite clamp on it down there.

so there you go. didn't stop it. Not terribly surprising I Thought you know I'll give it a go, but you only have to get one case like that for it to fail and it's not. You know it's obviously it still doesn't mean it's not getting through the HDMI cable.

You know, getting on, getting into the receiver in there may be doing some SCR latch up or something like that in the monitors detecting that. And as I said, it's probably got some sort of like watchdog timer or something like that and it just like resets itself. something else is latching up in there. It kind of detects that, which is really good and fixes itself.

So I guess that's a pretty good design, but yeah, it's susceptible. This one here does it. It doesn't do it. This one over here doesn't do it.

So something very specific in there, but that's pretty hard. Even though if you put it through, you know compliance testing and stuff like that I don't know. Compliance testing for monitors. You know whether or not they do some sort of ESD test or anything like that.

No idea. if you do, let us know in the comments. but even if you do that, you know there's so many injection powers and different ways to go in there. it's infinite.

You can't possibly test them all. So there you go. It's not that I have to do some more work on it anyway. Hope you found that interesting.

I'll link in my really old videos at the end of this. it was actually a three parter. So anyway I hope you found that interesting if you did. give it a big thumbs up and all that stuff.

catch you next time.