It's another tear down. Yes, it's another LCR meter. We love them this time it's the Agilant U7 33c. It's the new C model as opposed to the B model which I just happened to have.

So we'll do a side by side tear down comparison you beauty. and uh, the B was the original Escort uh design when the Agilant bought out the Escort Design Group uh that became their Handheld Instruments Division or something like that and this was the old traditional Escort design. so it'll have Escort branded I think an Escort custom Uh device in there under many sold under many different names. but they decided Agilant not they'll redesign it themselves.

It looks identical, but I've been told that uh, the new C model is the proper Agilant Handheld Test Group design from the ground up so we'll see what the differences are. Let's go. You know what we say, don't turn it on, take them apart now. as you can see, they've stuck with the same case design.

The Uh B model was uh redesigned with the new orange case as uh, you know the new Agilant stuff is all the fancy orange which I rather like actually and the new see. they haven't really changed the uh look, um at all. It's uh, pretty much an identical case. They've kept the same molding by the looks of it's got the same C markings molded into it so they haven't really uh, changed that changed that design at all.

but uh, the interface has uh changed a little bit. uh because this is a uh, more uh functional instrument with more Uh ranges and frequency ranges and functions and stuff. So they've got some extra uh stuff on the keys there. But apart from that, well, you can't tell the difference.

But I think we might see a big difference when we crack these things open. So let's do it. And on the battery holder here, that's actually one of the screws. There's two screws up the top.

there are self tappers. uh, rather unfortunately. But of course you never have to take these things apart really. Um, but there is a metal uh threaded uh insert for the battery holder.

which is nice because LCR meters don't have a huge battery life like uh, like, you know your multimeter might have 2 300 hours or something like that. These things have 20 or 30 hours, uh, battery life so you often got to change them. Would have been nice if they used Double A's or something like that which would have gave which would have given greater capacity but they've stuck with the 9vt versions anyway. let's uh, take it open.

This is the C model and uh, there we go. not extra turn on the screw required. There we go. t Tada Beautiful.

It's it's feature packed so that's the new C model down here. and well let's crack open the B model and the older one and see what the differences are. Well some now what we've got is the new C model on the bottom and the older B model on the top. And clearly they've taken the existing design and use that as a reference and just uh uh, change some Uh things around it because a lot of the Uh components and even that layout is Uh is quite sort of similar between the two.

But uh, clearly they've um, you know they've changed a few things. The Uh processor looks like it's changed. We'll take a look at that, um, the ADC which they had up here before in this big Um So package is gone. probably replaced by this device here.

They've changed the Uh buzzer there to a different type. They've changed the input protection. We have a um RF uh bead here for uh that looks like uh for the DC input down there, that's a DC input circuitry. They've added that just for some uh I.

The input protection is, uh, different. We'll go into that uh later. It looks a lot better on the newer one. The older one up the top had a glass uh M205 fuse up here.

Where is the new one has Uh Ptcs and Uh Poly switches and um, it looks like some Ms there or something like that di protection. So as a there's a fair few differences. but you know there there is quite a lot of um, old school, uh analog circuitry on there. It's very, uh, traditional LCR meter layout.

They really haven't started the design completely from the ground up and go right. We're going to fully integrate all of this and do some custom. Asic They've just used you know, 74 series logic and analog switches and pretty old school LCR meter design, but there's nothing wrong with that. They've also done away with the Uh sampling caps up here.

Look at those. they're big through hole uh caps there. and they've They've really completely done away with these. On the new boards, look at the size of that monster and uh, yeah, they're completely gone.

They've got a Um in circuit programming header up here. that's most likely a JTAG in circuit uh programming interface for the Uh micro, so you could read that out, hack it, do whatever. Um, and well, you know, apart from that, there's not a huge um, you know, I Expected to see um, fairly dramatic, uh differences. but I Just see, you know.

Sort of a minor second second design kind of thing based on the first one. But I guess that makes sense if your existing design worked H You don't want to tweak it too much. you just want extra Precision maybe extra frequency range, put in a few more modern uh components things like that. But apart from that, there's uh, not too many differences.

Little test points are still the same. Oh gee, I don't know. I'm struggling. uh.

another thing looks like there's a dual IR um transmit and receive Um interface whereas the old one was only uh transmit. You can only uh, transmit data out of it. This one can receive. Probably because you can do, maybe firmware updates, uh, through the Um Rs232 port or something like that.

Now let's start at the DC jack on the new design. Uh, down here there it is. the external DC input. All of this stuff around here would be uh to do with that uh DC input.

They've added the um RFI um Ferite bead here for some noise uh suppression on this thing. uh, probably to help it uh pass. uh C uh. compliance.

They've got uh, some diode prote section here. they've got looks like there's another uh Power diode in there and they've got some resetable uh fuses here as opposed to the glass uh fuses. So um, really, you know they've changed out a significant amount compared to the existing one, which was, uh, reasonably old school and not much in terms of um, you know, modern overload protection and, uh, stuff like that. And we are looking at a REV one PCB here.

Rev 01 I Don't know, are they expecting a lot? and they've really beefed up the input protection on this thing. They've got no less than uh, now, four uh, PTC uh, poly switches in there and uh, curiously, they' got three of these uh, glass, uh devices there, some sort of I, don't know what? Are they? Some sort of spark gap input, uh protection device surge protection device, or something like that. So they've added quite a bit compared to the old uh B design which has old M205 glass, uh, fuse. really old school stuff.

There's one uh poly switch down there and well, that's about it. There's a couple of dodes in there as well. They've also got those. some of those on the new design, have they? No, they're part of the Uh battery.

uh, input, external DC input, uh, circuitry. but yeah, really. um, input protection? they? They've pretty much gone to town there and they've kept the same, uh, single wire blade, uh, banana terminal system soldered directly onto the PCB down there on one side of the blade. I don't you know? I've mentioned this before I Don't particularly like this design, but you know it's okay.

It's not my favorite there, that's the B model up the top and they they really haven't uh, change that at all. The reason I don't like it is because one side of the blade there effectively is fixed and it doesn't spring and then any. Every time you plug something in, you're you're putting a little bit of force probably on that solder joint. so it's probably not the best from a long-term uh design aspect point of view, but presumably they've tested it.

But yeah, I don't know. It's just not as good as some other implementation as I've seen where the Uh blade, um, where the blades are solded directly into the PCB down the bottom at multiple locations like that I think just there's a little bit of force extra Force being uh uh exerted on that uh, solder joint there. It probably would have been nice to actually solder it on the other side of the board. so then it it wouldn't actually be on the bottom side of the board.

it' be on the top side. so when you push down on it, it would push down on the board so there's some physical retention there as opposed to just the solder joint anyway, eh. And of course they're stuck with the same uh battery, uh system PCB Mount uh, 9vt batteries and I Love that there's just no wiring inside this unit. Ah, beautiful, That's how it should be.

I'm not sure if the processor has changed, but as you can see, it's a 78f 0485. whereas the original design had an escort uh, branded, uh chiping there, it was actually escort. Whether or that's the same device and escort, we're just getting them to label it uh, different I don't know, but uh yeah, it's um It's seems to have changed anyway. and the main ADC in the new design is the Ads 1243.

It's a 24-bit 8 channel. um Delta Sigma ADC it's got you know buil in PGA uh with a gain of 128 and it's got you know, 50 60 HZ uh Notch filters in it so it's a very capable and a uh, fairly substantial step up from the Um from the TLC 71 35 which they used in the old design which is a, uh, more traditional uh, dual slope, uh 4 and 1/2 digit um integrating ADC which is just over 14 bits you know, 20,000 count resolution something like that. So they really have stepped up the ADC in this thing. Okay, we'll just go through some of the devices we' got on here.

There's really, uh, no surprises at all. That's a HC 74, Hc12 is an Opa Uh 2364 opamp more and Opa 2376 opamps. um H74 HC 4053 um, ah jeez, what else we got another Opa Precision opamp. This is actually a Um Max uh 7400.

that's actually an eighth order low pass uh switched cap filter they've got in there. So um, they have actually got a switch cap filter. go figure. And uh, once again, another 4053 couple of 4053.

We've got another Opa device. It looks like they love these uh TI Opa devices. They're absolutely obsessed with them. There's another three, um, Three Precision 2376 down here.

Precision op amps. Um, and they've got some Maximum devices here Max 43 82 There, an 8 channel uh Max and well, apart from that, a few more Precision Op amps and yada yada and there you go. That's um, inside a typical uh LCR meter design. It's really, um, hardly any different to the previous design.

Oops, and I missed that one up there. That one's actually a TI 2711 uh low? Power Precision Op A And now of course this one up here is the E S Prom for the processor and the 4 mm banana sockets down here are quite nice. They got recessed uh, metal, uh base in there like that with metal threaded tapped screws which go through there and there's the uh uh input, um uh, blade terminals on the other side and uh I thought they were just sold it onto the top so I may stand corrected. Uh here these are actually better than I thought I Thought they were just sold on the top, but they're not.

They're actually a through hole device which does go through to the bottom side of the board there. so that is, uh, a lot better than I thought. But obviously you can see that when you push that in there. It's really only this bottom side here which moves.

This top side has a a bit of spring to it, but you know it's it really is. Uh, it's putting a bit of stress on that solver joint, but it's not nearly as bad as I thought. So I declare that to be okay and as you can see, there's a really, um, nothing on top. No surprises there, just the rubber membrane.

uh, keypad like that and that's about it. Um, we've got the polycarbonate front window. the LCD There'll be nothing under there. there'll just be a couple of zebra strips uh, top and bottom or just at the top side there and that's about it.

Really have no problems with the Uh board at all. It's uh, first class quality. Uh. Construction seems well laid out, well designed as you'd expect from Agilant, and inside the back of the case, they've gone to town on the shielding.

uh, of course, very common in these LCR meters. The old one is exactly the same. They haven't changed the thing there and the PCB is only held down with that one screw there. and the three screws on the Uh banana Jacks here.

plus these two little um, plastic retaining Clips on the side and it does actually fit in there quite well. Got no problems with it. So there you go that's inside the Agilant U17 33c LCR meter I Like it. Have no hesitations in giving that one a thumbs up.

And next up, we'll have to do a review of this thing and uh, compare it with the Uh previous model and see how it handles itself so that'll be, uh, quite extensive. I think uh, so it could be a little bit of time before I get around to uh doing that. But anyway, the internal constructions of beauty I'll catch you next time.