Hi, What time is it? It's myth-busting time. Yes. Cordless Anti-static wrist bands. None of this rubbish.

What do you want? One of these annoying anti-static wristband cords? Four screw that you can buy these on eBay for a buck. They're cordless. They're supposed to work. Can you smell what? I Smell Yeah.

Thank you to the anonymous mailbag person who spent a whole dollar and set this into the mailbag cause you can't really buy these on eBay for a dollar delivered from China And rather than just go ahh, they're obviously there's no way in hell these things can work without dissipating the charge down to ground. Just like your regular cord based systems here plugged in the ESD point down here. they're obviously right. Anyone with any engineering knowledge knows this, but hey, let's do it the scientific way.

Let's put it to the test. get some quantitative measurements here and see whether or not these things are. Behold, the cordless anti-static wrist strap looks just like a real restricting to here, but it hasn't got the proper study for the small one or the larger stud here to come along and pressure caught into like this oh no, siree. Bob It's got some wireless magic voodoo inside here that dissipates all the static charge into the ether.

So unlike your regular anti-static wrist straps which have no internal resistance, they just connect directly through to the stud on the top. There your one Meg safety discharge resistor is done inside the lead here and also an extra one sometimes inside you. And the point that you actually mounted to that This thing actually has it built in. Well, because you can't just have nothing built in, can you? There it is.

It's got a 1 Meg resistor built inside here. a plus. Or the Voodoo Magic No, do its hair down at the end of this. But inside here you can see that looks like the leg of the resistor in there, so that just makes contact and this just folds over like that.

so we'll see what's inside here later. But yeah, this is just designed to be worn on the wrist like that. That's it. And it's supposed to be as effective as a regular anti-static wrist strap.

And to get some quantitative measurements here, I've got the exact tool for the job. This is my Alpha Labs surface DC Voltmeter. It's designed to measure surface charge ESD charges on mats and things like that or other objects without actually touching it. So we can actually use this stainless steel.

SMD Stencil here. It's just a convenient conductive surface and we can measure the charge on this. We can put a charge on this map, we can watch a discharge, and we can actually get a real quantitative value in Kilovolts. This thing goes up to twenty kilovolts I think it is or more.

and we can actually get a direct readout in voltage of any sort of charge that we ever build up or we discharge from this supposed wrist wrap. And just to show you my setup here: I've got the ground of the service DC Voltmeter going down to my ESD mat here. I'm just using that as a reference surface down here. I've got my Keithley 240 high voltage power supply.

It can go up to 1200 volts. I've also got the negative of that reference down to the mat here. So by connecting this metal surface here to the output of the power supply, we can use this to actually calibrate our system and show that it's working. I'm just doing that for a bit of fun.

We could just trust this, but hey, why trust it? Let's actually try and do a little bit of calibration first before we do it. but then we can use this lead to actually our discharge. I Can charge myself up, touch it, charge the sheet, and we can once again use this to just discharge to my Earth Mains Earth reference star. ESD strap down a ESD bonding point down here now.

sorry. It's not particularly easy to get both of these in shock because this has to be exactly level with the surface down here. Exactly one inch above. That's where it's actually I calibrated.

It's got a little disc on the bottom. It's calibrated for that distance Anyway, what we can do is when like this, we can plug it into our output here and I can reset this so we're at zero volts there. and I can actually turn this on up to 100 volts. Bingo! Look 101 volts and we can go all the way up to a thousand volts.

It's a little bit out. You know if I actually move this up and down like just a tiniest amount, it will art change. but you can see that that is perfect and we can actually look. We can go five hundred and then we can go negative as well.

And it shows negative charge too. No problems whatsoever. Systems all calibrated, ready to go. All right, let's give this a go.

now. this isn't going to be the world's greatest test today because I don't have synthetic underwear or clothing on or anything like that. Do have a jumper on. but you know, like we're not going to be able to generate tens of kilowatts.

But it doesn't matter if we can generate via charge study charge build up a charge on that plate. We can check to see whether or not this cordless wrist strap dissipates any faster than your regular corded wrist strap. So what I've got here is one of my real corded wrist straps. but I'm not going to connect it through to my earth bonding point.

This is to actually connect via this alligator clip. lead here through to the charge plate so that charge plate will be at the same value as me because it's not dissipating anywhere. It's just connected via this direct connection here. So if I look you can see it on a second camera here set up on this surface.

DC Voltmeter You can see I can build up a charge there and it slowly dissipates because of natural dissipation and shoes and a natural dissipation of the system. That's no problems at all. So I can. let's go I can like give it a little charge.

Okay, so chose up the plate and I can actually zero that out by boom connecting the plate and hence my body through to directly onto the earth bonding point down there and as you see, it went down to zero. Now first we'll try my real anti-static wrist strap. Here we go: I've got it not connected to anything. So once again, I can build up a charge on that plate.

Okay, and it stays there and it just naturally dissipates a little bit. But here we go I'll plug it in and then it goes straight down to zero because it's a one Meg resistor. It dissipates the charge really quickly from my body. no problems whatsoever.

Now let's do the exact same thing again with our woo strap here. patent pending. Okay, and I'll turn it around like that. so it's on the beer part of my skin like that so people can't claim or you got hairy skin and all that you know, sort of stuff.

And right? So here we go. We don't do exactly the same thing we did before and let's see. Mmm what? what? what? wha? It's just doing its natural dissipation, that's a phase part of the system. This thing is not accelerating that discharge at all now.

I Can I get the stopwatch out and time it and everything. and I Yeah, who cares. Look, it's not doing anything. The charge remains on my body, its remaining on that plate.

And it doesn't matter whether it's you know, a thousand volts, 500 volts like this, or whether it's ten or twenty kilovolts, this thing does nothing. Wow And let's do a side-by-side comparison test. I've got both the Wus strap and the real strap on my arm. Here we go.

Let's up. Sorry I didn't put that back on properly. Here we go charge up our plate. no problems at all.

It's pretty slow to dissipate isn't it There we go, but of course we can go at that. And WHAM soon as I plug in the real strap, it dissipates. I Just realize you may not have been able to see much of what I was doing there with that real strap. There we go.

I Just had that hooked onto there hooked onto the plate. That's it so that my body was definitely connected through to the plate and it wasn't dissipating anywhere else. Alright, I Know some people will complain or try and generate a bit more higher voltage, but I've been experimenting here, haven't had much luck at all. I've actually got my art synthetic well walking pants on synthetic polyester shirt and I've tried all sorts of very shoes and my jumper taken off and on and this is about the best I can get here we go I can start it from zero there and here we go.

I've got no Restrepo all and you know I can get work too our thousand or something like that and slowly dissipates I've actually changed the amount on here I had the Art of Electronics book before I've actually just propped it up with some batteries so it discharges slower now, but you know that's pretty much the best I can get sorry so we'll just try that again. Here we go: got the good anti-static wrist strap and Bam there we go. discharges and I got the woo strap on here we go. Once again, we're down to zero there.

Charge her up tonight and it's not doing anything, it's just the regular discharge rate. Ah, hopeless. So this thing is an absolute crock. so let's take a look what's inside this.

My bet is it's just a one. think resistor flapping around in the breeze. Here we go, let's have a look. Tada.

look at that look at that. there's our one MIG resistor in there and that's it. Wow Unbelievable. It's actually broken off there.

It's yeah, that just fell off so a door. Oh did I have a faulty one? I doubt it and that's it all I've got. Is that not there? there? We've got a captive nut to hold the plate in and that's it. It's just a screw attached to a resistor flapping in the breeze.

That's it. That's it. That's the whole thing. It's an absolute con.

ha. No real surprise. So there you have it. there is the cordless anti-static wrist strap.

It is a complete con. It is just a one mega resistor flapping around in the breeze and as you saw, it didn't work. Of course, it didn't work. Anyone with any clue whatsoever about how static charge and discharge works knows knew that this thing wasn't going to work with.

uh, you know people. go. Oh, it's only a dollar. I'll just get it on eBay It's not even worth the one freaking dollar.

It is useless. So there you have it that is totally busted or discuss it. Evie blog forum link down below. Catch you next time.

Ah, by the way, Yes, the rumor is true I do actually work in the lab in bare feet pretty much all of the time. and well here's one reason why not. I think it's the most comfortable thing, but hey, this is a nice side benefit. Check it out.

Here we go. This is with this is where shoes on. Here we go take the shoes off Tada. let's ground it in and look at that.

not even generating clothes and bill. not even get in to 100 Volts Beauty! So nothing wrong with bare feet in the lab unless you like step on an upturned oh I see and then ouch. Catch you next time you.