Next up we have something from Lei Chi thank you very much Lei he's from Malaysia Panang in Malaysia Don't forget to look at the Malaysian stamps again. Okay, not a problem. Lovely. Birds Fruit and flowers.

Beautiful. All right. this one is a uh, rather largish box. Oh I Thought there was a gap along there.

No there, we go along the front here so this could be anything I Have no idea. Oh HP HP Seral see serial Port No, it's not sure it's SATA Power Cab. No sure it will be something else entirely. Hi Dave Thank you very much for an interesting EV blog.

As I mentioned earlier in the Forum I'm going to send you a handheld pulse generator for your review. The reason I built is handal. Pulse generators allow me to perform do it yourself passive probe. Yep, um another reason allow me to verify the bandwidth of and step response of my probing system.

Of course we've done some videos on that and a few people have sent some stuff in. uh when I hook up the pulse generator blah yep the riseing fall time35 on uh that's for a Giian uh response bandwidth. Um, it generates 1.4 nond rise time. Four time is a bit slower at 1.9 With this, you can verify up to 250.

MHz So yeah, it's not particularly quick. It's not like the Jim Williams uh pulse generator that is in the order of you know, 300 p or something like that. But thank you very much Lei Happy mailbag Day! Wooo! Let's have a look and we have a most excellent Uh 50 Ohm 2 W uh dummy load uh DC to 1 gig. Fantastic.

And he's also included. uh two signal conditioning kits from Pulse uh research Labs I Hope you can use them. So excellent there. Looks like this just comes off here.

Is there anything in them? No. Okay, they're just a uh, they're just a blank uh board. which then you can, um, you know, uh, do your own, roll your own uh, filters and stuff like that so that's they're very handy that's really nicely uh engineered I Rather like that, wonder how much they cost and there you go. Here's these signal conditioning kits.

and uh, up to terminations? up to 5 gig? Oh beautiful, Yeah, these it. It feels like it's that sort of quality. Ah that's for the SMA ones, all 3 gig for the BNC uh version which we've got depending on PCB uh, depending on the substrate they're using I guess and on the back here is a neat little uh uh sample Applications: DC Blocking Of course you can just put the AC couly cap in there. um AC block which just has a choke in the middle uh series Termination shunt termination configuration: Precise shunt termination uh feed through decoupling cap Doo Detector attenuator Low pass filter High pass filter Beautiful.

And here it is: Don't turn it on, Take it apart. No worries, we will take it apart. Overshoot: 3.57 Uh, 3.57 4% pre-shoot 1.1 to 1% getting pretty precise there cycle Jitter Less than 600 p a seconds Uh Peak to peek. Ah, look at this man.

it's got everything on there. It's the L711 pulse generator. Fantastic! There's a nice BNC we' got some test points on there. not sure what the up dip switches.

it's a right. it's a it's actually a pulse generator as you can set it with the dip switches 1 khz 10 MHz Logic Z or one. Excellent I Like that battery included. Please connect before use.

there you go. Use a standard uh 9vt uh, takes about 70 milliamps. That's actually that's a lot from a 9volt battery. but uh, patent pending? really handmade handmade in Malaysia That's a nice case.

I Really? Uh, quite like that. That is neat. So there's our battery. Yeah, that's really nice.

big thick screws on there. Let's take this sucker apart. Tada There we go look at that neatly designed. it's even fused.

beautiful And we have a little bit of uh, bodess Happening Here on the board. Eh, few little last minute changes, but uh yeah, that's actually. uh, quite neat. That is, uh, well designed into that case.

I Really like that. and if we have a look at L schematic here. As you can see, there's uh, not much to it at all. We've just got some output filtering down here.

We got a 74 HC Uh, 4851 we a 7 HC 390. Uh, 2 390s there. and uh, not much else to it as far as the power supply section goes. Got a soft power on switch here and uh, looks like there's a low battery detect circuit and a Um virtual ground with an opamp there just generating the virtual ground in the middle getting the positive and negative rails and he's using an Opa 875 uh MX there to drive the output directly from that so it just looks like it just chooses between uh, the Uh reference and ground and that's it.

and I haven't uh decoded this one at all in terms of the uh uh actual operation of this, but there seems to be Shenanigans going on here with the Um HC 390 flip-flops to generate the pulses required. Hence, the RS and C's in there. So let's give this thing a go. I've got it uh, directly connected into a coupler.

Of course this is a 50 Ohm capable Uh scope, so the input is set to 50 ohms input impedance and uh, we'll give that and give that a go. Press our button Taada and the rise time there pretty much uh, bang. On to what he said: 1.4 odd nond there you go. And and the fall time there? yeah, around about 2 NS he said about 1.9 but yep, close enough.

Now the thing is, it's um, just a square wave. Um, so I don't know what all those uh Shenanigans were going on with the RS and C's around the Uh flip-flops. the HC 390s. uh, not sure what's going on there at all.

I Expected it to like generate a uh, a shorter pulse or something like that with a different uh duty cycle, but no. Anyway, that's the 10 MHz option wh just switched off. it's got auto switch off mode on the switch there. it only goes for about 20 seconds or so.

So that was the 10 MHz waveform. This is the 1 khz waveform and same duty cycle 50% duty cycle. and uh, if we go in and have a look at the rise time, yeah, there it is. the same 1.4 OD nond and the four time there yeah, around 1.9 to2 nond.

same as the 10 MHz waveform. Now I'm using what Le calls the logic high output level and the thing just switched off and it looks like it's a I don't know designed to generate a single pulse or something like that. So I think his terminology might be a bit wrong. but check out as it's decayed like this, check out the weirdness which is happening as the uh as the power supply voltage discharges.

Really quite neat. So if we trigger on the positive going edge here, I'm going to push the button and uh, see what we get there we go. We just get a single edge which oh that does not look clean at at all. That's very nasty.

So I'm not sure what mode that thing's actually. uh what that's actually designed to do. It's a bit weird and there's that same Decay you saw before over time that same weirdness happening as the voltage drops and finally decays and then drops off right at the end there. Neat.

It's fascinating. The effects you can get with uh, you know, when power supplies do weird stuff and you wonder why your circuits do weird stuff when you power supply does weird stuff? Check that out. Try and model that on your bloody simulator and see what you get? Huh? So here we go. I've managed to capture this thing on the what L calls the logic low mode and uh, I You know, look it, it's attempting to generate pulses there.

But look at that. I mean you know, yeah, we might be getting a uh, a falling Edge there. um, sorry, I've haven't sampled that properly. It's all over the shop of course to all those um RC's doing stuff, but there you go.

Look, we're generating. look. It looks like we're generating a sharp positive Edge there and then a yeah, some like a Shar an alternating sharp positive Edge and then a sharp Negative Edge Um, in that case I Guess it's kind of rather clever, but uh, yeah, I just don't sort of understand the benefit of that at all. I've sampled that a bit better and well, the falling Edge there is you know is is hopeless I mean we're talking, you know? 3.8 microc.

so I'm not sure what's actually what's going on there at all. the uh, the uh Rising Edge there is reasonably quick, but yeah I don't see what mode that is at all. Le Please explain. but on the regular signal generation mode, that really does give a nice response.

you can see there's very little overshoot. There's very little pre-shoot there at all. Very little overshoot. I mean this is only only a 500 MHz bandwidth um scope.

but you know that's that's pretty good. I Like it. Next up, we have something from France from Thomas Salandi. I'm sure it's not Salandi Thomas well it could be I don't know.

um I don't know what the uh if that's normal to put your last name first on something like this, but uh, this is a rather interesting box. I like this. Um, there you go. There's a French stamp.

Not really, it's not even a stamp now it's just printed on there. Hopeless Loser. All right. One old mobile phone.

Woohoo! There we go. Must be a bloody big mobile phone of course the uh Motorola one we uh, tore down ages ago. There you go. Thomas Salandi Thanks Thomas He's a geek and a photographer Or a geek photographer and Sf.org however you pronounce it I'm sure I've got it wrong anyway and is from Paris Dave I Can't thank you enough for everything you taught me in your videos and of the fun I had listening to the ampow with Chris hi Chris this was uh, my very first mobile phone.

It was pretty old when I got it required fulls sizee SIM card made me feel very important every time I pulled the antenna. Hope you enjoy taking it apart. All this Thomas thank you very much. Let's look at what Thomases first.

Oh my good. Oh right, that's the oh, it's the micro tack. There you go. It's the uh, oh yes folks.

Oh, state-ofthe-art Has it. Got that old electronic smell? Hang on. Oh yeah, Isn't that just a thing of beauty? Look at that. a state-of-the-art technology.

Oh, pull the antenna up. Oh, you're a big shot, you know? Wall Street broker or something like that with your M Motorola microtac Mobile phone. Were they don't? Were they even called mobile phones back then I wonder when that term actually started? I don't know I have a vague recollection that they weren't actually called mobile phones. Then they were called uh, portable phones or well, cell phones in the US Um, something like that.

So not sure when that terminology came along. but there's the charging station for it I Wonder if it uses nickel metal hydride? probably? Uh, sorry. Um yeah. Well, Nikad or nickel metal hydride So let's whip that off.

let's have a look. Doesn't tell you? Bommer Yeah, I'm guessing that would be Nikal nickel metal hydride probably. And there it is. It's the Motorola 7200 microtac made in Germany Well, as it turns out, this thing's actually fairly recent.

It's 1994 vintage, so well, it's almost 20 years old still, though. But it's uh, not one of those analog ones from the 90s. This is a digital uh 900 MHz GSM model. So it's actually far from the Uh analog bricks that we had back in the day.

And if we have a look at the uh weight of this thing, what does it weigh? let's have a look. 250 G4 of a kilo. Ah, it's not too bad, so thank you very much. Thomas that will be the recipient of a tear down.

Tuesday Coming to a video blog near you, the Uh charge is interesting too. It just slot. Well, yeah, fail. It does slot in there like that.

and it has another slot down in there. Uh, presumably to charge a spare battery. Or at least, uh, that's the plan I Suspect There we go. Yeah, that's the idea.

You whack the battery in there and you can whack your phone in the front. Or you can whack two batteries in there like that. It's actually rather neat and modular. Can Char Looks like you can probably charge two batteries at a time.

Um, as well as having that third one ready to go on your phone. Wonder what the Uh battery life on this sucker was? And just to even it out, we've got one from JP in Willoughby here in New South Wales Australia not Austria Let's check it out. Paid a whooping $865 to post it. Thank you very much JP wonder what it is doesn't actually say cuz there's no you know, no need for Customs uh forms.

Of course you send in stuff internally so let's keep it open. Mystery: Oh hey, it's a can of something. Oh look, check it out. All right, let's have a look it's we've got some flux in here.

sorry some sold. Yeah! Oh, look at this flux gel. There we go. Flux Scene: PCB Cleaning solvent awesome, complete with a little brush there and nozzle.

and we've got some flux gel. brilliant from um, Aim solder and there's no yes, there is. there's a letter hi Dave I'm glad that you do like the probes. Ah, of course George is the one who who uh, sent me those um sexy little probes.

In regards to the solding video, please try out these two products. Been using them for years and they work well. Yes on the schmart B Apply the flux flux gel around the chip and blow hot air from your 8N hot air station until the flux gel starts to boil and solder melts down. That will trim the solder joints.

Yeah, it would probably uh work a treat I'm sure after this let it naturally cool down and clean with the electr lube flu. now as should see a nice Factory looking solder work. I'm also using this, for hand soldering and it works great! Yes! I Have no doubt, thank you very much. George Yeah I don't have any of this um gel type uh flux I've only got like the flux uh pen I've used this uh, sort of stuff at work before, but I've never actually had any at home and I've actually used this before as well.

this uh, flux clean stuff from Electral Lube um they make you know a ton of stuff and uh, here's the stuff I actually have in the lab here. it's a more general purpose electronic uh cleaning solvent once again from electrol Lube in the familiar package with the Big E but this is just um, isopropanol. uh, alcohol. What's the percentage? uh yeah, you know, 99.7 pure um% pure isopropanol alcohol.

so it's different to this flux scene stuff I believe which is, let's have a look. Does it tell you? a rapidly drying blend of solvents for removing contaminants from print Circ boards and flux residues after soldering test sport area before using on Plastics Well, you know a lot of your components um, on your board are going to have plastic packaging. There you go? Uh, doesn't actually tell you what's in it? h Nope, there's no information on that at all. It's just got a blend of solvents.

Yeah well. anyway, um thank you very much. George I Will uh, definitely use these two next time. I do a solder in video.