Hi Got an interesting tear down for you today and thanks to John from Mordale here in Sydney for setting this one into the mailbag. It was too good for the mailbag. so we're doing a dedicated teardown video. We love aircraft instrumentation teardowns because they're always rather fascinating.

And this one's even more fascinating because it's Australian beauty. It's a Microair Avionics T2000 Series, Atc, Rbs um, otherwise known as a Uh transponder. It's an aircraft, uh, transponder for this one's I guess for light. Or you know it's not for like, your 747s or anything.

It's more for light aircraft. uh, transponder. And anyway, um, designed and and maybe made in Bundaberg in Queensland. World's best rum up in Bundaberg, Queensland for all you rum aficionados.

Anyway, it does comply with various standards around the world, so this isn't just an Australian one. I have no idea if this is, uh, operational or not. Anyway, it's a transponder system that is part of the Air Traffic Control the Uh Tcas, or the uh, you know, collision avoidance uh system where the air traffic, uh, controllers they, um, send it or other uh planes for that matter. can, uh, send out a signal on a thousand and thirty megahertz and this thing's just continuously receiving a thousand and thirty megahertz.

Uh, and then it'll actually, if it gets the signal, it'll respond with a unique code and uh, the aircraft altitude as well. If you got it in a certain mode, there are different, uh, certain modes for this thing. Anyway, we've got antenna input and a D25 output. I don't know what that is, Maybe some Rf adjustments would be my guess anyway.

But yeah, so it receives on 1030 megahertz and then it returns what's called the uh squawk code on a thousand and ninety megahertz. So that's how it returns the unique Id and you can actually set up your Airtra if you enter a new Air Traffic Control airspace. Uh, they you know should contact you and say you know please, They'll give you an identification and you apparently enter it here and stuff like that. Sorry, I don't you know, I'm sure the uh, There's like quite a lot of pilots on the Who watch the Eev blogger and on the Euv blog forum, so I'm sure they don't tell us all the technical details.

But anyway, it's got a dual line dot matrix screen here. I have no idea if this one works. Um, and but yeah, um. designed and probably manufactured here in Australia.

So let's whack this open and I think it's about 140 watts our total transmit power. That'd be like the peak I guess. Uh, something like that. Um, so yeah.

designed to receive and transmit on the Uh one antenna and well, let's crack her open. Nice screws on top and bottom. Uh, the front panel. Yeah, that'll all pull out.

It's very nice. as is common with uh, these aircraft instrumentations there. I I presume that these are like a standard uh, slot size that you put all your instruments in. They're designed to like.

you know, go into the cockpit in, uh, well, you can put them anywhere I guess. Um, any location. And uh yeah, you dedicated wiring harnesses. and then you can just chop and change or choose your different types of instruments and they all fit into like a standard rack size.

I don't know, I haven't looked that up. I'm sure it's a standard size. Just sit right back and you hear a tail. A tail of a fateful teardown.

One instrument had landed on the bench for a five hour teardown. A five hour tear down. Oh, and immediately we're in. Like Flynn.

Look at that. Love it. All accessible, beautiful, shot in glorious 4k for your edification. And uh, there's the Krusty.

Uh, D25. Can you see the shiny gloss on that board? is that got a little bit of a conformal coding on it? Wouldn't surprise me to find a conformal code in there, so some sort of like option board don't really know, but uh, a couple of melts down there. you know? I'm a Milf fanboy. Yeah, but obviously given the D25 so I haven't looked at the Uh pin out for this.

If I can find it, I'll whack it up there. But uh yeah, Obviou. This can interface with various Gps's like Garmin and others are to get the altitude. uh, like you know proper altitude information or it can hook up to barometric, uh, pressure sensors which you can get the altitude information from that anyway.

Not sure if that's part of a system, but genuine Hot's not up there. So to stop the To220 flapping around in the breeze, another run, what's it? They've bodged. oh that's a that's a diode Is it? Yeah, it's a deity. and uh yeah, they bodge that in more hot snot down here once again to stop the uh, capacitors vibrating flapping around the breeze.

because obviously you get a lot of vibration on an aircraft. So you know if you just had a free standing To220 package like that, it would vibrate loose in next to no time. Trust me. I have experience in this where um, just stuff in a production environment that was wheeled around on a trolley.

you know, even with like a trolley with big like pneumatic tires on it and stuff. the vibration of that, you know, doing that, you know, every you know, like for three shifts a day, every day for you know, six months is a year or something was enough to just um, vibrate just the to220. It just vibrated loose and just like snapped off it. Just the fatigue on the legs of this thing.

the vibration, it just hit the you know, like it was the right resonant mode or something and I just were eventually just um yeah, fell off. so that happens. So anyway, um yeah, nothing interesting there. We've got a processor, we might have a squeeze.

There you go. The microchip fanboys go wild to pick. Uh, 17c, 756. Is it? um, this design by the way, dates from uh, 2000 so I think it's still in, uh, production.

Actually, I don't know. You know these things often wouldn't uh, change over the time. This is the sort of application that you would have that would, um, you know, pretty much not change. You just keep buying the same pick microchip part.

That's why you can still buy, you know, pick micros from, you know, 25 even 30 years ago, maybe something like that. So anyway, not that unsurprising. The picks have a good following, especially here in this, you know, designed in Australia, this would have been like a go-to or microchip would have been a go-to micro solution back in 2000. Stuff like that.

So uh yeah, when was this one manufactured? And of course you see how I peeled off the firmware sticker there and it's like left a big hole in the conformal coat. For those who don't know, you can formally coat boards to keep out moisture from uh, being an issue and like you know, causing leakage on a board and uh, mix it with enough crud and you start getting like low impedance shorts and that can ruin your day. So yeah. conformally coat? uh stuff.

very uh, common to find in aircraft and military things like that. You know, industrial stuff where moisture could be a problem and this side here has to be our Rf section. So ta-da Oh, it's upside down. All the electrons are going to fall out.

Oh there you go. Look at that. That's not your regular Fr4 Pcb. is it new, Siri Bob.

And we've obviously got some distributed elements. Uh, Rf goodness going on here like that. For example, is a capacitor a long trace like that is an inductor you got to remember at Rf frequencies. Even traces, they start becoming inductors.

They start becoming capacitors. and when you have a large pad like that. So this is effectively this could be say an inductor capacitor to ground because there'll be a ground plane under there and then another inductor. So that could be an Lc filter.

And actually it says receive filter input there. Uh, plus 50 volts down there. So now I was going to say is there like a must head amp? I don't think so. Um, this is this is the big power job you look at that it's obviously going.

It's bolted, that'll be bolted down to the heatsink block, which is, uh, underneath. No doubt. Absolutely sure of that. Looks like we've got a little tuned cap there.

So yeah, that's our transmit section and this would be presumably our received section if I can get that cap up. That was a bit rude, wasn't it? Ah, there you go, goes under. Oh oh okay, right. Oh, it comes back like that.

Okay, so it comes around like this. controlling pins and then oh okay, and then it goes through a pin there. All right. That makes sense.

All right. so that's incoming, Got an Um Lc filter, and then, yeah, that must bugger off onto the bottom side of the board. So we really have to get this board out. But don't you love the ceramic power packages? Try and pull up some info on these.

Um, yeah. Beautiful. Sure, they cost a small fortune. manufactured by Nude Virgins and uh, terrific.

I don't recognize the uh symbol on there so, but I'm sure if the Rf aficionados do. Um, look at that. That's interesting. Like why that trace there with a whole bunch of Vias and just a cap going over to it.

That's fascinating. Hmm. Anyway, um, it's not a huge amount in the Rs section. You know you need an Rf.

You know, a power amp. Uh, here. And you need an Rf receiver and Rf filters. and that's about it.

I mean, it's you know. Probably very simplistic. And there's the front guts of it. I love how, uh, all that look at that.

That's just one big machine piece of aluminium there. Absolutely terrific. There's not many wires going off, but uh. there you go.

That'd be another pick. There's absolutely no reason to suspect. Uh, that wouldn't be probably be the same part for bomb reuse, is it? Yep, You betcha. That's the same.

No wackers and not much else, I'm sure they'd have a good quality encoders, you know, Alps or something like that, perhaps. And that's just a little Lcd backlight down there. And that's just the Lcd interface connector. That's all she wrote.

But anyway, it's a nice, neat little compact design. I really like it. Well, there you go. That's obviously a specific power supply border.

He didn't I thought it was integrated with this one before, but it's not. It's its own interface. This little puppy here is not going to reveal what it is. Um, this starts to get interesting.

You'll see that the D connector is attached to the. well, it's not attached to, but you know it's surrounded by that middle plate on the back and then that, ah, bloody hot snot and that just pops out like that. Got a little oh, a bit of insulation there, and uh, discreet wiring inside this thing. Not unusual.

Uh, to find something like that. Oh, look at the Milf resistors. Oh, I gotta love the Milf Milf mouth mouth. That'd be a real pain if you forgot to put that, uh, back plate on before you actually soldered that D connector in.

Um, yeah, that'll ruin your day. but you've been there, done that kind of thing. So there you go. There's a little slot in there, which is not wide enough for the connector, but well, it's got some ferrites on there too, but I'm sure if you whack it through at an angle, you could eventually get that out.

So, or in or out. So yeah, it's all sort of, uh, integrated together of course. Um, you know, prices. No objects that they're not optimizing this thing for.

Uh, you know, high volume assembly or something like that? I don't. You know, I'd only make like thousands of these a year or something, it wouldn't be. uh, you know, hundreds of thousands. So anyway, uh, yeah, so you know.

Look that. wires solder. That's a power supply output obviously going over to the transmit and the Rf board. and it's just got wires soldered on there.

So yeah, you've got to desolder those. So there's a specific assembly step and a specific unassembly step which involves soldering. Hmm, yeah. so it looks like we're going to have a transmit block here, and a received block over there, and little, uh, penetrators going through, each with little, uh, ferrites on them.

That'd just be for uh, power, and uh, maybe some uh, control and signal. And that's about it. And there we go. There's the bottom of our board.

You can see that penetrator come in what I presume is the transmit block here, and this would be the received lock. A couple of little ten turn trimmers down in there, and uh oh, that's some 74h logic. Nothing particularly special down in there at all. There's a bit of analogy goodness.

maybe a couple of Op amps and things, but uh, not much. Again, this is on a special, uh, you know, like a probably some sort of Rogers uh, controlled impedance material. They're tightly specifying this. No doubt you wouldn't just farm this out to one of the five dollar Pcb makers in China, that's for sure.

Um, no, you'd want to. It'd all be specifically saying yep, I want this Rogers material. Xxx. Um, and yes, please.

If you desolder the penetrator down there, you get the board out. Uh, 11 3 Is that 11? I don't know if that's no, it's as a serial number. Triple 1, 3, 1, 1, three. don't know what that is.

Um, but yeah, you get that out. and uh, yep, it's all. um, no traces on the bottom there. Of course, that could be a multi-layer board.

I don't think it is. I think it's all that's a there. I think that's a single layer jobby. There it is.

for those playing along at home, capture that in 4k. But yeah, you can see the uh, you know it's serious Raf engineering the uh, typical cans. You know, if you do like I've done spec, I might have to link in like a good spectrum analyzer. Tear down on stuff like this and you'll find these sort of, you know, individually, uh, shielded modules like this on controlled impedance boards with, uh, penetrators are the go-to thing for getting signal and power between modules.

Two stubborn screws in there, but this will all pop out. so this is the shielded can. Ah, there we go. No wackers.

Oh oh, there we go. There's our channels. Oh okay, aha, check it out. This is where the input from our board came in.

So this is obviously some sort of, uh, cavity filter. They call it a cavity filter because there's actually a cavity in there. It's an Rs cavity filter. Um, I've seen these as like, um, like a tubular coaxial? Uh, type ones.

But yeah. Look, you can see that each element has a tuned slug inside, so you're able to tune each one. So that's like a five element tuned cavity Rf filter. Isn't that fascinating through there? So there you go.

That's what's on this side, and it looks like there's another one under There is there. I can't see any other reason for these shorties here. Um, hmm. Well, I wouldn't expect it like a like a five-stage cavity filter in in something like this.

I thought it was a, you know, fairly simplistic application. but but maybe they need this to get the discrimination uh, required. So um, yeah, on the transmit side or the received side, I assume it's the receive side. Yes, Dave, of course it's the received side because I, um, we saw the power transistor going directly to the output before and this, if I flip this over, you might remember that.

There you go, there's our Rf filter. So here's our input coming back from our receipt. Okay, coming back from our antenna. This is our input controlled impedance trace little itty-bitty element filter there on the board and then that goes into oh yeah, the receiver filter input and that is our receive filter.

Looks like, you know, a five-stage um, Rf cavity filter tuned? Look at that. So some gray bearded nude virgin at the factory has to, uh, sit there and tune all those Brilliant. I'm going to get this board out of here too, but everything has a procedure, so I've got to get this Bnc off before I can desolder the pin on the other side to then angle the board out. So yeah, we're going to have a little leftover bits.

All right. I got the pin down there, desoldered the all the screws out and everything, and flappity-doo-dah Oh hello, hello, um, the surprises aren't done yet. The Rf goodness got a bit of rigid coax there. isn't that fascinating.

Wow. I I would not have expected that at all. But anyway, aren't these just beautiful machined blocks? Absolutely fantastic. Obviously this is the base of our uh, output power transistor there.

As I said, it just goes down to the main block. Use the entire case as a heatsink. but uh, what does? what's that Richard Coax doing? Hmm, so check this out. It seems to goes from over this point to over to here, which the only thing it seems to go to is a little trimmer cap on the end there.

So is that some sort of like tuned stub? Something like that? perhaps? Wow. Fascinating huh? Fellow engineers pray with me. So there you go. if you are tuned cap aficionados.

There you go. That's just like right on the end of that rigid coax there. So yeah, and it comes from the output of this bad boy. Here I presume it's an output.

Lots of little umbridges that we'll call them. why not 4k screenshot. Aha. I originally thought that this was a cavity uh, filter.

but it's not. It is a what looks like a comb. what's called a comb line, uh filter and you only notice this if you get it out and you can see the um, the ports down here. They've got little plastic uh sleeves inside to then put the little uh tuning.

Well, they're usually you know they're often like screws tuning, uh, screws. but in this case these little aluminium pins just slide inside there and they cut them off to a certain length and they tune. uh, these. So some gray bearded nude virgin sits there and uh, tunes these things and then they seal them up with the plastic on the end by the looks of it.

And but the interesting thing about this is that I was wondering why like these lengths down here were different lengths and I thought, well, maybe it formed part of the cavity. You know, because when it was all together, I thought, oh, you know, maybe it's all like shares a cavity, but it doesn't and you'll notice that there's no insulation here whatsoever. So this is all connected to the chassis block. This is just basically.

Well, there is a hole in the middle of going down here. But apart from that, look at the pins. Okay, the pins. There you go.

They're just soldered onto the aluminium block. There, That's it. It's not like they go through any insulation to a cavity inside. This, I believe is a comb filter.

I'm sure the Rf aficionados will correct me down below in the comments, but basically, um, this always freaks me out. right? Because this is actually connected down to like. This chassis is grounded so effectively what you're doing is shorting the output of the antenna. Here it is the output of the antenna.

Okay, is going basically through copper through copper. Sure, these are little inductors, right? And you've got an Lc filter there. But then that goes directly into here. So you're basically at Dc.

Mind you, hold on to your hat before you launch into the comments. Uh, Dc. Um, then it's You're shorting the antenna output directly to there. But basically it comes into here.

But because it's one gig, but even shorting direct, effectively shorting directly to ground here. Uh-uh you ain't doing that at one gigahertz, right? So it's um, effectively. I'm surprised. It's like it's not going into like, the top bit here.

I'm sure the Rf aficionados will, uh, tell us why. But anyway, it's going. um, it's basically going directly into here. and then they're using these as also, um, part of the uh, tuned comb.

So this is a comb filter. And uh, here's some. Like I found an online comb filter calculator. It's not accurate, but you know, just? here's some possible.

You know you can calculate, uh, these sort of things and how they work. and you can get different types of, uh, cone filters and things like that. But yeah, this is shorted directly to the chassis. You've got the signal.

It's this always freaks me out like it's just. you know it's it's Rf voodoo, right when you have the output of the antenna shorted directly to your metal case. Yet it works because it's one gig and things operate very differently at high frequency. But yeah, that's it.

There you go. It's a comb filter with some of the combs actually, you know, um, milled into the grounded chassis. It's absolutely remarkable. Um, yeah.

Anyway, I'm sure the the Rf aficionado aficionados are really getting excited about that one because that that really is just amazing. I'd love to, uh, talk with the designer about that one. Yeah, I'm I'm just surprised. Um, to find this sort of thing in just a, you know, a one gig uh, transmitter and receiver.

Well, this is a receiver filter. It's not a transmit filter, so very interesting. Please leave it in the comments if you've got more detail on that. So there you go.

that's absolutely fascinating. Uh, tear down and I'm sure a lot of our Rf aficionados will, uh, really appreciate the uh, design effort that's gone into this. uh, bad boy. There you go.

single-sided board. If anyone can recognize the material, please leave it in the comments. But uh yeah, that's much more Rfe goodness and um, certainly more screws. Look at all the look at all the screws and washers and and things that I expected to find in here.

I expected. you know, an output power trinity? Be bolded to the Uh chassis and that's about it. I didn't expect like, uh, cavity filters and um, other stuff that was seen in here. So anyway, um, if you've got any idea why they need to go to that sort of effort as I, I can only think that, or you know, it's uh, discrimination.

Uh, signal discrimination? Uh, requirements for you know, the standards or whatnot. Um, but yeah, that's interesting. So yeah. cavity receiver and the output power driver? What is it? Like a three stage or two stage thing or something like that? Anyway, I'm sure somebody will analyze that.

So as I said, always very interesting. These Us industry specific bits of kit aircraft electronics. Absolutely fascinating. So if you like that, please give it a big thumbs up.

As Always you can discuss down below in the comments or over on the Eevbog forum which each forum each video gets its own forum thread to discuss. That's what I've been doing for the last 12 years almost since day dot. And if you haven't joined the Evblog forum, join it. And if you haven't joined my other channels over here, please do.

I'm currently like 44 000 subs on Odyssey or something like that, so I'm still like like top 10 in the world for Odyssey uh, subscribers growing hugely and I very rarely say it but thank you to all my uh patrons as well. I've got like 1300 uh patrons or the link is always down below and subscribe star as well. Not a huge growth on subscribe star, but I've got like 17 subscribers over there on subscribe star so thank you very much for all those who support the channel. Catch you next time you.