What's inside an $18K 20GHz handheld spectrum analyser?
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Hi, What's inside an $18,000 Agilant 9344 C 20 GHz Spectrum Analyzer Well, the people at the RF Design division at Agilant thought we'd like to know, so they sent one for the tear down. You know what we say here on the Evev blog? don't turn it on. Take it apart. So unlike tectronics who were scared that I would break their precious Spectrum Analyzer Agilant Uh well the RF Design Division said yeah, no worries.

take this, tear it down. have your way with it. Beauty Thank you very much the RF Design Division at Agilant for supplying this. Hi I can see myself reflective screen on this thing.

Um, we have the N 9344 C Geez! I wish they'd get B better model numbers that I mean who pulls that one who pulls that model number out of their ass? Really fair in anyway. 1 megahertz to 20 gigahertz Awesome! So we're GNA have some excellent RF uh Magic in here. Fantastic handheld Spectrum analyzer. Real high-end bit of Kit As I said, about 18,000 Australian dollars designed for field use.

It's got over molded rubber around the outside just in case you drop it. it's really Hefty I don't know it's at like 3 and 3 kilos or something like that. and um, it's got a nice little springy stand on the back. Oh look at that.

Oh I can play with that all day long. Nicely screwed in there. Looks like would uh survive I Don't want to rip that off, but yeah, seems pretty rugged to me. It comes from the Uh Chenu Instrument division at Agilant Technologies from the marketing department.

Hello Song Tan good on you. Um, so this is obviously one of their demo units or something lithium ion battery in there and uh, we'll take a look inside to see what's in there, but let's have a quick uh peek at the top here, shall we? What have we got here? We've got our RF input here 50 mm of course, our 50 ohm RF output both end connectors all standard and that's for the tracking generator of course and it's got little protective caps on there Beauty external trigger reference GPS Antenna very nice. You can get some uh, nice applications with that external power for the charging building landan USB headphones as well for getting the modulation output fantastic and a uh user interface on the front. We're not going to turn it on because we're going to take it apart.

It looks like there's a few torqus screwed on this thing, but this one here is a oh look like a Phillips smells like a Phillips but I ain't getting anything on that if I get my Flathead in there. hang on. no smaller. Flathead There we go.

We've got some sort of Port here I wonder what that is Ah that's the that's the battery. There we go. We'll take the battery out. Uh Tao Electronics There you go.

4.6 amp, 10.8 volt must be recycled. Oh look at that battery gauge on it. Beautiful. Fully charged I Can smell it all right? We got $20,000 instrument smell and uh it looks like oh yeah, look at that even First cab off the ring here I probably can't won't be able to see in there but they got little Springs attached to the top of the case all the way through there just to put some extra uh downward force on the battery pack.
Nice attention to detail there I'd probably have to turn the uh uh contrast up for you. uh the there you go. You can see them nice in there so it doesn't vibrate and all that sort of jazz. so very nice attention to detail I like that.

That's a good start. So let's whip this puppy open and uh we have a Torx it must be a T10 I had a T15 in there. There we go t10s the ticket and of course um I'll post some links to uh Spectr Analyzer tear Downs or RF tear Downs I've done before and uh we are my is my oh my Torx isn't going to fit in there oh bugger hang oh I can just get that one there we go. All right yes folks, it is tear down Tuesday there we go.

300 p.m. hopefully I can uh finish this before I have to head home? apologies if I can't but anyway, we expect to see inside here. Um, not much on the processing side of stuff. We don't care about all that sort of stuff, you know it'll just be a uh, some sort of processor I'm not sure whether it runs like embedded Windows C or something like that most likely run sort of some sort of embedded OS but uh, yeah, not too fast.

What we want to see is inside the RF cans. Of course they'll be all uh, fully machined cans with RF shielding gaskets on them. and uh um, we will see lots of uh PCB, uh uh component technology as well. lots of inductors and stuff um, embedded into the PCB and capacitors, and uh, various components and way and um, band pass filters and things like that.

All sort of. There we go, all embedded into the PCB which won't be a regular material, it'll be special controlled impedance and uh, it'll be very, very nice these spectr metalizers. They cost a lot of money for a reason and uh, to get 20 gig bandwidth is, uh, quite quite an achievement. There we go, we're straight off there we go.

Tada. Oh look at that. Look at that Beautiful. Oh there it is.

Precision Machining Look at all the look at look the big fully machined aluminum blocks there. for all the RS stuff. we got some rigid coax down here. We'll take a look at Ah to Fpga to display Com and on the back of the case.

Here we have little slots for the Uh handle on the side. Looks robust enough. um I Guess I would have maybe have liked to have seen that be screwed into the aluminium blocks or something like that just for rigidity. but uh, obviously a uh, quite a uh, good quality, impact resistant uh, polymer plastic they'd be using on this thing, no doubt.

But interestingly, have a look at the Uh shielding tape they've put on there. that'll be some sort of, uh, you know, a Ferite impregnated um shielding tape or something like that. Um, I don't think that is regular tape tape there, folks. So just a little bit more shield in on the back side of the case I Think But isn't this a thing of beauty? Look at that.
Ah, fully machined aluminium blocks. You can see the Uh PCB wedged down in there. There it is. you can see the PCB down in there.

And so they've got a top shielding block, bottom shielding block. So if we take off these top Shields we' be able to see the top half of the board. then we'd have to get the board out Pres the C components on the back side of the board. Then we've got another board down in there.

and then we've got at least a uh, third board right down the bottom there with its own cover shielding plate. And there's that rigid, uh, coax. I Was telling you about joining these two blocks here. so they got that rigid coax.

Um, you know that'll be like 20 gig bandwidth or whatever they need. Um, there looks like they got SMA connectors on there going from board to board. Look at all the V's on there, Look at all that V stitching there to get the impedance. get the inductance right down.

So fantastic that one's got A and they've got um Center Mount board connectors in there mounted right on the center so the pin that comes out doesn't. We'll probably see that when we take the board out. The pin's on the top side and it goes direct. The center pin uh sorry, is um, on the well, the bottom side of the board here and that's connected directly to the correct width trace on the bottom side of the board.

so there's no pin which comes out and then goes right angle down like that because well, at 20 gig, that sort of stuff matters. So look down in here. looks like we have some Stus status LEDs down there. They're not marked though, but uh, obviously there some sort of internal uh service status.

We've got some sort of that could be like a JTAG programming or debug header or something like that. We've obviously got another uh um, uh micro, uh board, uh coax connector on there and uh, probably use for another optional something like that. But then we've got some regular coaxes going around to here, which then we follow them around. Let's have a look at where the inputs are.

So oh, here's our RF output. So here's our RF signal output. Then we've got rigid coax there. So this is our generator board.

so that looks like probably I'd say that module there as our track Eng Gen. Perhaps it makes sense to keep it completely separate and that's why. Then they've got the join going out like that. So then the output frequency of this can go into the tracking.

So the sweep uh, frequency in here of the spectrum analyzer. this would be the Spectrum analyzer module. Then that can drive the track Eng gen over here. completely separate.

Of course, you don't want any, uh, cross talk between those at all. Absolutely essential. And then here's our main RF input here. very short.

rigid coax. Of course. if you don't know, um, what rigid coax are, they're uh, various. Uh, Technologies go into them.
but it basically feels like it's like a complete, uh, copper rigid outer pipe. I Mean there's no flex in that at all. It's not a regular cable. it's basically a solid coax cable that's basically what you've got there.

And um, then we've got out. Yeah, that's our, uh, what's that? That's our external trigger input. And then we got a GPS they. oh, there, there's out.

There's our GPS antenna there. it is. Just spotted it. There, it is there.

we've just. it's just got a patch antenna there. nothing. Uh, particularly special at all.

GPS module that goes off and then the external antenna over here. So it looks like they've got an internal patch antenna and then an external optional external antenna as well. so it will work with the internal antenna. You can see it's patch antenna due to that Center Point and then the uh than the antenna pad on the top there.

So typical patch antenna. Their performance isn't that great, but certainly adequate for getting reasonable. Uh, well, you know something out of the thing. Anyway, So there's our G Yeah, our GPS antenna goes around external trigger.

so that's the external trigger coming around here. The external trigger is going down to the main board, so the trigger is not going into the processor. Of course, it's not going into the Spectrum analyzer module up there. Um, what else have we got? Then we've got our what else we got.

Interconnect wise, we've got our main processor board here. Going up to our the looks like the bottom. Well, there's one board. There's one complete board going across both of those modules.

So I'm presuming the Spectrum analyzer module here in the track Eng CH looks like that second board there goes all the way between the two modules. So interesting. But uh yeah, obviously you got to connect the processor over to there. and and we just got some flat Flex here going down to the keypad display, whatever, some dip switches, and uh, not much else.

But uh, interestingly, there is of course going to be an Fpga in here. There's a display. looks like we can take off this uh panel here and there we go. We got our J tag for our processor and our Fpga as well.

and, uh, interestingly, I Love this. Check it out. They've got a big inductor there. Obviously, it was, uh, too high for the main.

you know, for the main to get under the main cover. So they went. Oh buger it. Let's just put a little cut out in there and then we'll put the Uh plate over that.

It'll all be nicely shielded anyway. Beautiful. But check out that. I mean even the plate.

They've had to machine out a cutout in there, so it doesn't short out the pins that actually, uh, aren't flush with that. They do. Those pins actually stick out a little bit there. just you know.

attention to detail. That's why these things aren't Mass manufactured in there. Tens or hundreds of thousands, you know. So they can afford to just machine a single plate just to do that.
Brilliant. Now, of course, to get all this apart, I'm actually going to have to take off these rigid coaxes here. I'm going to have to unscrew those, Get a spinner in, and, uh, unscrew those suckers out. And by doing that, I'm probably voiding the calibration on this thing.

of course, because when you're talking about a 20 GHz bandwidth uh, connector like this, even the torque on the thing matters. Um, really, really. Or it very likely could. So, uh yeah, the odds are that.

uh, you know I'm not going to damage anything by taking it off, but um, the thing actually might need a recal after this. Um, certainly. And off we come. and they should just pull out like that.

So there you go. There's a 20 gig rigid coax and there's a closeup money shot for you connector afficionados. And of course, each rigid coax has its own uh, you know, custom assembly and is, probably you know, individually tested and uh, characterized as well I wonder how much just that individual component costs them? One of the things I love about this uh construction with all the uh machine solid aluminium block is like this connector is not going to break off. You know you get some heavy hamfisted production or field operator or something like that and look, it's just you know, screwed directly into the full Chazzy of this thing.

Unbelievable. and I love it when PCB Layout people. uh, put these uh visual layer guides right on the side of the board. They just bring the copper right out to the routed.

Edge One of the dangers with uh that of course is that you can actually short these out. Now a bit of context here if you're not sure what you're actually looking at. Um, you got the top aluminium block up here. sorry I got this propped on an angle.

it's going to bounce around a bit. bottom aluminium Block in here and the PCB multi-layer PCB wedged in there. This is actually the uh, tracking Gen module or what I believe is a tracking Gen module and you can count the copper layers in there have a look oh my. point is not.

uh, fine enough but 1 2, 3, four, five, 6, 7 eight layer board in there obviously U you know, alternate ground and power layers in and uh, stuff like that, but uh, that allows you to see the actual copper in there and that there if you're wondering what that thing that is obviously an RF gasket on there sealing the top of that board. That's what it looks like Anyway Now of course, if the layout person is smart, that won't actually be that copper. There won't actually be connected to anything at all because of course you could easily get shorts on the outside of this board when it's routed, snapped, or or whatever. or you're connecting to something you know, touching metal next to to something like that.
you can short it out. So what they'll do is just. well. I'm not, it's not on the side I Have to show you a top view, but they would just have an isolated um Island uh pad in there which isn't connected to anything, just floating copper which then goes right to the edge which then gets routed off when this board gets machined now.

I think I have all the screws out for this top one this top Uh connector module up here. Tada there is our Spectrum analyzer module. uh, well, presumably uh, well, the front end for it. Anyway, it's probably the front end.

probably a lot of the spectrum analyzer stuff is on uh, that um, secondary board down the bottom and we got our track engine there. but oh, look at the number of screws we got to take out and look at that board to board interconnect. Tada of course that's not uh, taking you know RF frequencies and stuff like that. it's probably only taking the Uh lowest frequency out to the Um analog to digital Uh converter.

plus all the Uh control signals and stuff like that of course. so that doesn't need to be particularly high frequency. and this pink cover here that just comes off is likely just a thermal pad like a seill type uh pad just to get good uh uh, thermal coupling between the block which presumably gets, uh, quite warm and the rest of the aluminium here which can also act as a bigger heat sink as well. And there's that board to board interconnect for those are curious in such things.

There you go, you can see the center power connect Center power uh, tabs down in there they can carry reasonably High current? uh, likely. anyway I don't think they just or they could just be ground um, shielding tabs or something like that. These are, usually, um, quite, you know, high frequency connectors, but obviously it's not being used for here for the um, you know, the highend RF signals that's all contained within the block. So as I said just uh, control and probably the final um, if um output as well or that might come via one of the coaxes over there perhaps? and I think I got the screws out here.

These have some uh screws on the bottom, so I'm not going to get this top plate off without taking out this whole board. Yep, Yep. Yep. there we go.

Probably some interconnects, yet there's some interconnects down in here and uh, that sort of stuff. I'll be able to show you that in a second, but there you go can disconnect those not terribly exciting stuff down in here. you know, like I you know? would you even bother taking that off? It's just the Um LCD controller. So yes, there's absolutely no shortage is shielding on this thing.

There's the Uh LCD display. It looks like it's an NEC model NL 6480 or something like that I don't know I don't think I'll even bother taking off. uh, that and then you've got your keypad down in here. That's um, not what we're here for today.
There will be some microcontroller goodness under here, so let's check it out. Check out that big um pulse uh brand, um in inductor there or common mode choke absolutely massive sticking out the bottom side of the board. There there we go, look at that, we're in like Flynn and interestingly check out the bottom here thermal pads that actually uh, molded the aluminium uh plate so that it actually um, used as a thermal uh, you know, heat sink um designed into uh connect onto all of the major Um heat generating packages in there. Brilliant bit of systems engineering I Love that lot of thought and attention to detail has gone into that thing.

and you can see the thermal um seal pad on top of each one of those chips lines up. So you know there's got to be a, uh, a lot of of um, you know communication going on between the PCB layout guys and all the mechanical uh housing guys and all that sort of stuff. So excellent work, well done. Huge thumbs up on that.

Well now the really interesting part about this, which I didn't expect to see is uh, yet more shielding blocks inside here. Um, my only guess would be that would be the um analog to digital uh converter. uh, something like that. This one's got a relay, uh, poking out of it there by the looks of it.

Um, but yeah, so it's obviously taking the uh input um signals from outside the main um Shield here. rounding them under the outside shield into these shielded blocks, you can see all the uh grounding vs. all the way around the outside of those to add some extra shielding, lower the ground inductance yada, yada, yada. but uh yeah, obviously those um RF well, intermediate, uh frequency lower.

You know it's not the full 20 GHz bandwidth. They actually, uh, mix that down to lower frequency before it goes into a relatively uh, slow analog to digital converter in the you know, uh, tens and megahertz range. We'll have a quick look at a couple of major parts on here. We got ourselves an Epson S1d 13748 uh, LCD controller.

Nothing special is a bit of a beast. It's got 1 Meg SRAM built in. and then we've got our LCD driver up there. and there's our LCD interface cable.

and there's our DSP Analog Devices uh 21 363 Yes, it's one of those shark uh processors we've seen a lot recently in Ryol gear and other stuff. Bit of a beast uh, 3M internal uh SRAM and that's coupled directly into an Actel Fpga there, which we'll have to take a look at by peeling the sticker off. Then up here we've got ourselves a crystal uh, ethernet uh controller. nothing else major on this side here.

We' got some memory down there and uh, that looks like our main processor I can I think I can see arm down in there? because basically we have Uh three, Technologies uh coupled in here. We've got our DSP which would be doing all the heavy lifting in terms of um, the stuff from the analog, uh, and stuff from the Adcs down in here. and then we've got an Fpga It's just I don't know, doing some glue, uh, logic, some really fast, uh, process parallel processing or something like that and then, well, we don't know the complexity of that one yet. And then we've got our main processor over here, which would be uh, controlling the user interface and everything else and you probably can't read that, but that's an actel iGo SL you know, micro semi um Igloo AGL 400 V5 So that's actually quite a size of Fpga 400 K Gates about a $50 Fpga And then we've got some nice looking power supply stuff up there in the corner.
Beautiful, nicely laid out High current traces. You can see that we got more power supply stuff happening over here here and uh, you know, lots of little uh, local regulation and uh, core voltages everywhere. But yeah, that pretty much does the business. It looks like we have a real time clock down here.

you can tell from the 32 khz watch crystal down in there by the looks of it and a little tiny package external. RDC and that about does it for this side of the board. So I suspect there's more on the other side, so let's flip it over. Nothing terribly exciting on here.

some more power supply stuff. There's that huge pulse common mode: It looks like it is a common mode show because it's near the DC jack right up there that you saw out poking out of the shield. uh, before. Just some more memory down the bottom there.

And uh, we've got our realtime clock battery. We've got the bottoms of our Shields which will take off in a minute. Micro SD Card: There's no card in it, but it does certainly have an internal micro SD card slot no idea what that's for and more power supply stuff. Well hello, We have a couple of bodge wires under here.

look at that? There we go. Some enamel wire going from that Trace over there over to there. another little bodge in there. There you go.

Well, you know the complexity of this thing and I guess they couldn't be bothered resp spinning the board they just found. Oh yeah, let's just. uh, hack that in there a bit. No drama at all.

Let's take a look at what that puppy's doing there because um, I'm presuming that the tracers obviously come under the shield in here from these two connectors here. I Believe from memory, this one wasn't actually connected to anything but this one here certainly was. And surprise, surprise Ad 9235 12bit ADC 40 Meg samples per second. This mod down in here is interesting.

Take a look at this. There's a that looks like a zero Ohm jumper there and it looks like and they've got that enamel coated wire going over there so they're like joining those grounds together. Interesting. Did they have some sort of uh, grounding, uh, problem or some sort of uh, performance issue or something like that they had to fix I don't know.

quite unusual and the back of that uh, shielding block there? No surprises, just all the uh, bypass and other miscellaneous passive stuff well underneath the other block. Um, there's not much at all, but it looks like um, for example, like the here's the RF connected down here and there's another one here. So like that's going to flow into here somewhere. so it looks like, um, you know, it looks like we've got some RF trans M you know, probably like an RF transistor or something like that.
I'm not sure I forget what was actually connected to this uh Point down in here. And of course, one thing we've been missing so far is the 10 MHz reference oscillator. and there it is. It's a rayon.

Um, we'll get in there and have a look at the particular model number, but uh, looks like we got a couple of devices up here. we'll check those out. We got it. looks like another 10 MHz oscillator down in there.

Oh, and I think I see a bodge cap and no surprises as at all to find a clock generator such as this: ADF 41 200 MHz um programmable uh frequency synthesizer. We' got an Ad 829 Precision opamp there and down Here is a little bodge cap tucked in there. hello, look at you. Um, that looks like a um another Uh oscillator looks like a 40 Meg oscillator.

There it is 4 Meg 00 and there's the rayon VTX 0210 A-5 10 MHz uh presumably temperature compensated oscillator with what looks like a trimmer cap on the top there. Unfortunately, that's not going to work anymore because it is now. um, upside down. And of course, with these uh Precision reference oscillators, you can't have them upside down down because all the crystals just start settle to the bottom.

It doesn't work anymore. And for those playing along at home, this is PCB Rev Three. So what we've got here is our main reference oscillator and frequency synthesizer which then gets multiplied up of course in frequency in the Uh tracking generator and other parts of the system. secondary oscillator down here.

Not sure what they're doing with the secondary oscillator, but then our ADC under this block here and that is what gets you know all the low phase noise of this spectrum analyzer. Really good oscillator, really good mixes higher up and stuff like that in the RF block. So I think it's time to take the RF block apart but you'll see the uh, the machined aluminium uh cover that they went to. all that trouble.

They sealed off all the individual sections all under their done it properly built in braces. They got a couple of test pads over here on the side of the board. but uh, as far as like, uh, production test pads and things go. I Really? Um, you know, don't uh, see anything else on here in uh, terms of that.

So all the uh, you know, they just assemble this board and you know, do the basic, uh, basic programming of the Fpgas and all the programmable devices and then they, um, just do thorough, thorough, um, you know, softwar defined uh tests in the things and calibration. You know, all that sort of stuff. So they're not actually doing a huge amount of test at the bear board level. I suspect.
And it goes without saying. I Think that the soldering on this board is first class. Just a tip for the young players: when you're reassembling something like this, make sure you have the cables actually sitting outside before you put the shield on. Don't All right? That was a fair few screws, but let's hey, lift this off.

Oh, there's our there's our gasket. A tada look at that. There's our gasket. Beautiful.

What's that made out of? Lovely. look. there you go. That's the material.

It does feel metallic in some way, but uh yeah. I'm not sure if you know the exact uh material actually used for this RF gasket. Please leave it in the comments. So this is our tracking Gen board and I think it's going to just lift out because really, it is just, um, shielded like the I don't think there's oh there? No, there could be a board to board interconnect over here or something like that just for some control.

uh stuff. But of course all the RF goes through. uh, the connect. Oh yep, there we go.

board to board, interconnect. there it is connects down to the bottom. I Thought: you know you can tell by the traces in there. Kind of a dead giveaway.

and there's another gasket on the bottom there of course. Beautiful and all fully machined. each individual section. of course we I won't go into details.

We've seen this in RF Spectrum analyzers before. This is a Rev 6 Board of the track engine N 9342 and uh, that is Tada Oh there it is. There's our track Eng Gen and yes, Tada we have our first look at some PCB uh, filters and stuff like that all in there. There we go.

Typical RF And you know how I mentioned before about the uh center pin of this thing. uh, coming through the top of the board? Well look, it's actually completely shielded on the other side. There you go. So yeah, the top side is.

uh, of course you know there's no uh, center pin popping out there and on that side, no nothing. it's all contained in there. Then it's going through to an inner layer through, probably popping up there somewhere and going wiggle wiggle wiggle wiggle into there and across. and we could be here all day trying to look at this thing.

but uh, this is rather interesting actually. Look, they've put some solder on top of that Trace there I Wonder why? One interesting aspect to note is look, you can't actually see the holes in the V's there little micro vas obviously um used in this thing and uh, plugged of some sort. but you can see the you can see the signal coming in from the connector. here it to be going through a center layer like the it'll be going through here like this.

hence the uh, you know these are Vas around here to uh, reduce the shield around here and reduce the uh inductance of the ground plane and all that sort of jazz and it pops up here to the top layer. This is all controlled impedance. PCB VI By the way, it's not just regular stock standard PCB you get from any manufacturer very carefully. uh, very carefully characterized of course for controlled impedance applications and AC coupled there going into that device there I Have no idea what some sort of um, well I don't even know what this connector is used for actually.
So I'm not going to try and go through and decode every single part of this. Sorry folks, it's just not. um, not worth my time really. So I guess you could look up that I don't know.

Is it like a a RF amp or something like that? So I'm not actually sure what these devices in here are. haven't looked them up yet and splitting off and then we'll go through and we can start then seeing some uh RF filters and stuff in here and then coupled here. there's a RF uh transistor for what, an RF amplifier for sure. They've uh, and then it goes up here.

boom into another device you know, all over the shop. and then we start getting into the RF Wiggles in there. they just putting in an inductor in there. All right.

So let's see if we can vaguely follow the signal here. This is our tracking generator output. This is our 5050 ohm output here. It's AC couped.

There's obviously some drivers here, so we go in actually backwards, uh, through this process. So if we, uh, we've got a couple of other uh, well, devic I have no idea what they're doing I have no idea of the topology. We've got. obviously some filter, maybe perhaps a mixer down in here? Perhaps Then we've got some uh uh, filtering going on in there based on the PCB Not sure what that one's doing, that's obviously an RF uh transistor down in there.

Then it's going through you can see, then it just sneaks through a um Gap in the wall of the shield down in here. Then we've got another 424 Lt3 device that we had down here. We had a couple of those 424 Lt3s and then just off that we got a 74 Hc4 inverter. Look at that.

Brilliant. Not sure what that puppy's doing in there, but uh. anyway, we have some. Looks like we have, uh, some inductors there on the board and then, yeah, I'm going to probably get complaints about poking around on this board with a screwdriver.

Shut up. Really, it's not worth complaining about. I know what I'm doing and then it sneaks through. Ah, we got another, uh, well, probably amp there and then we or buffer and then we've got our controlling piece and pedance tracers going through here.

We got another device there, whatever that is and then we have some what's probably a band pass filter. I haven't looked at the topology, haven't uh, thought about it. but uh, as I've mentioned in previous videos, those traces out. You know, why do they have like a stub going out there like that? Well, that's actually an inductor in there and and it's got resistance as well and that actually adds acts as a capacitor there.
so you can actually have um, you know, low pass and uh, band pass filtering and things actually integrated into the PCB and that's exactly what they're doing there. And then we're going over to whatever this little hybrid is here. little aprene hybrid. It's a uh uh, Sim 24 MH whatever that is, then we're going into a ceramic package.

couple of ceramic packages over here. H 564 local oscill. ah, lo32. Okay, so they're presumably, uh, local oscillators down in there.

Then we have our main control device. We have to rip that off. see what it is? Not sure. We have our board to board interconnect of course there and check it out.

We have a board to board RF connector. Doesn't that look funky? Jeez. ET could phone home with that thing and there we go. There's the Ma in RF connector through there, so that's probably getting out the um, you know, one of the local oscillator signals or something like that over to our track engine and that's where we follow the signal around like that from our output.

way back here here, around there, through that what looks like B pass filter there through some local oscillators and stuff and back over to here. But then we've still got these, um, isolated sections here. Some more filtering going on there. Uh, you know it could be like a low pass filter perhaps.

and uh, but these blocks I Mean, there's a there's a connection between this block in here, like this, down to here. but it seems like that block is almost. uh, you know. um.

isolated. It could be something. There's obvious, there's probably something sneaking under through there, perhaps going from there, jumping over to there, and uh, yeah, maybe no, There's nothing going there. so you know these things are sneaking all over the place.

You got to be careful, but it almost looks like all of that is sort of its own isolated block there from this main path which sneaks around here like this all the way back there. anyway. I don't have a block diagram of the uh tracking gen I'm not going to try and reverse engineer it to get it out if we take the other Shield off here. we don't actually get anything all that interesting.

Look at that. it's pretty Barren so we should actually in. like we've even got some. you know, basic um S So8 packages here from Linear technology I Can see and we'll go in and take a look.

But here's the main uh RF input over here of course I have to take out that rigid uh coax before I lift this board out. but uh yeah, nothing exciting there at all. as you can tell by the tracers over there, that's another board to board in interconnect, same as what we had up here of course. and uh, there could be another RF board to board I'm not entirely sure we'll find out, but uh yeah, let's lift that board up.
There should be some more interesting stuff underneath, but all, first of all, once again, got our RF gasket there and uh oh, a couple of nice little traces in there we'll check out, but let's have a look at some of the chips on the top first. USA USA USA Well, this right here is a very interesting part of the circuit. I Really like this? Uh, check out what they've got happening over here and try snaking its way around there into this uh four? Leed um device I Don't you know it's like it's you know, a typical RF um, you know, amplifier, uh, configuration kind of thing. but you know it's just I Didn't expect it to see in a square, uh, plastic package like that.

sort of, uh, rotated. 45 Bizarre. But anyway, yeah, they've got some basic RF stuff happening there I don't know what that is? Uh, your guess is as good as mine and anyone's got any info. post it and we got ourselves a couple of bur Brown I Love Bur Brown Then our TI of course.

uh Opa 4251 uh Micr Power Opamps. Nothing at all special there. If we move up here I wouldn't even like to Hazard a guess on that that one. And then these devices.

They're everywhere. Check them out there we go. There's two of them there, there's another one over here, and then over here. same device.

four of them. and on the flip side of that, got ourselves the RF gasket again. Tada We have a couple of Yeah board to board interconnect and a couple of board to board RF connectors and oh, look at the back back. very sexy gold.

As far as the I can see. Unfortunately, not something that we're going to be able to take apart cuz these things are, usually, um, solded, completely shut. And yep, they are. You can't just pop the lid off that.

It's not just like an RF can. you can just pop the lid off. A bummer and we've got some interesting stuff happening down in here. Once again, no idea what that device is.

RS Section 8 At4 attenuator. Perhaps some sort of attenuator going on there. Low could mean a low pass filter is going on on and there. If you want to know where that is relative to the other side, that one actually is the same block as that, contains that funny little wiggle in there with, uh, that little amp or something down in there.

So that's the back side of that block and what we got under that uh, little firmware tag. there is an XC 2c1, 128 zyink that's actually not an Fpga that's a coolrunner uh CLD complex PL And we've got a couple of linear technology Parts all around that not sure what they're doing. Not going to look them up, just uh, little uh Precision op amps or something like that. Not terribly exciting.

Unfortunately, all the magic happens under these cans and we can't get to them. What's under that is that? that wouldn't be. Is that an access port cuz that looks like copper tape? A copper? no? What is it? Whoa. We got ourselves a little hole under there little access hole.
Wonder what's going on there? but that yeah is H sealed with uh, copper tape there? So Shield that you know we're talking about 20 gig here. Put a bit of spit back on that. She'll be right, no worries. But uh yeah, little access hole under each one of those.

Got those lovely board to board RF interconnects again. another LT part up there, but obviously not critical part of the anything outside of the shielder cans. Of course, nothing to do with the RF uh part of it. They're just, uh, basically, uh, control circuitry and stuff like that, so nothing of terrible interest like.

Likewise, this stuff around here. yeah, it's inside the um, uh, block over here. Here's our block. There, it is.

The block has its own, you know, uh, thing there, but obviously not quite as critical as what's deemed to be inside one of these shielder cans. But you know, still good enough to have all its own machine block and everything else. That reminds me I Forgot to look at the viice on the uh tracking gen board. Yeah, exactly the same zyink art.

cool Runner CP for basic control and interface. and somewhat curiously, this main block down here, actually for the track engine, has its own backin uh module on it like that. So there you go. Maybe it's you know, independently, uh, tested or something like that.

They assemble that as a block and then you know that's probably maybe a, um, a some sort of production, uh, test, uh, sticker or something like that and then they test that separately and then just Bol it on there. That's the most likely scenario anyway. but they didn't do that with the rest of it here. They just, that's all just one integrated block.

All right, Our 20 million bloody screws. Now there we go. Got it? Got it? Got it? Woohoo! Oh, check it out now. of course, none of this is going to make uh, much sense unless we do a basic block diagram here.

and that's what I've done of basically very, uh, top level block diagram of how this thing is going to work. Now over here, we got our RF input here. and there's our RF input. We're going to have our attenuator section.

Of course, it's a fully programmable attenuator. Of course that's going to be with inside this RF uh block here. actually. uh, second thought, it could be entirely feasible that this board is just an attenuator board and that's uh, basically it just doing the input, uh, attenuation stuff and then all of the uh band pass.

you know. So basically it could just be effectively, um, you know, just that on the front end. Maybe some extra filtering or something, but it's entirely possible that all of the you know the Spectrum the traditional Spectrum analyzer stuff of the local oscillator with the Uh filters and the mixers and everything else. The multi-stages of those is actually all done on the more complex board.
Really, it makes sense because the um, you know the performance of these things absolutely critical, that the input attenuators, and uh, you know, input preamps and stuff work Absolutely, You know perfectly. So that's why these are the only things that are effectively uh, double shield like this. I mean they've got their own shielded can inside the already shielded block. Absolute critical performance in terms of uh, noise, floor, and um, uh, stuff like that.

So yeah, I Reckon that's just the input board effectively, and that is likely popping out of one of our RF connectors here or here, which correspond to that connector there, and that one there. So that one Pops in just about there. sorry, this side here. Pops in on this corner over here that likes it that looks like it could be a band pass filter in there.

off to the ADC and then we've got all sorts of control stuff. or it could actually be this one over here cuz that looks like an extensive band pass filter as well. We'll take a good close-up look at that, probably a mixer somewhere in there I Don't know. I'm not going to follow this all the way through and trace it, but it's going to have that basic, um, uh, functional block diagram.

There's lots of uh, control, uh stuff and other things on here which we won't bother with. but of course the ADC as we saw is back on the uh main board. It's not actually on this particular board. There will be no surprises under there.

That'll be another coolrunner um, xylin control chip, but that's about it for the block diagram. Of course the ADC is then going to go into the DSP so all that is on the second board. so I don't know. These bloody Spectrum analyzers are incredibly complex.

Beast Let me tell you, I don't know if you want to figure it out. go for it. So there's our board to board. RF interconnect there and that's of course jumping straight through there.

You can see the lack of V as it's jumping through series termination resistor there through to here up to here and that looks like it's some sort of uh band P pass. uh, fixed band pass filter. Of course these big fans going off here. they're actually acting as capacitors.

We've got little inductors in there so that is going to form a filter and then of course the output of there looks like it jumps up into here into this device. Then it comes around here, some more filtering action happening there, and then we've got some more filtering. Another band pass filter. You might think, how does this work? It's not even connected well.

of course two plates like that is a capacitor so that signal can actually jump all the way over to there. No problem whatsoever. That's RF PCB design for you. Then we' got various uh, then we got another Um amp here here.

Then we have looks like a uh a Maybe that's like acting as a controlled impedance transmission line or something perhaps. So they've got a various mix of Technologies and we won't go into uh details on those. I've explained that a bit in previous videos, but apart from that that looks like it ends the RF Oh voodo, No, no there we go. We got another one over.
here. There we go. We got another filter happening over here and once again, instead of the fans, they've got the little pads there. lots of.

Technology Of course goes into actually, uh, designing these things and ensuring that their performance, um, you know, is is smack. On Target because you can get uh, better performance on the PCB than you do using discret uh components. It's you know, very controlled impedance material they got in here. They'll know the exact, uh, dialectric constant and characteristics of it.

They can program that into their Um RF filter layout programs, which then you can, uh, simulate and uh, design all these things. But there you go. that is. Um, there's lots of sections on here and I could uh try and decode it until the cows come home.

Unfortunately I have to go home. but I Don't think the Fun's over yet because if we pop it over I Think we're going to see a bit extra on the bottom here. Oh hello. In fact, we get a lot extra.

Look at that. Oh beautiful. Wow. that's more than the top.

Fantastic. We' got more little hybrid modules down there. I'm not going to look up the number. they're probably like, you know, from mini circuits or someone like that.

one of the uh, uh, providers of, uh, such thing. We've got some complex filtering. Network Happening Here Your guess is as good as mine. If any RF experts out there want to, um, actually, uh, tell us the exact um, uh, you know, uh, configuration and performance of that thing.

Please do. But that is absolutely brilliant. But as with all of these, you can see the signal flow. I Mean you know there's obviously signal flowing through just that little Gap there on the inner part of the board.

Then we're going through our complex network over to here. it's jumping over to here. This is probably jumping over to there more low pass and band pass filtering happening there. Another one of those hybrid modules jumping over there.

Once again, the signal just jumps straight through there on the bottom side of the board, goes up blah blah blah all over the place. And then these cans look interesting. Let's take a look at those and that's a Zedcom Crow 3750 A- LF That's a voltage controlled oscillator module and if we jump up here, what do we got? there? Another Vco by the looks of it, but another manufacturer Smdi I presume it's a Vco Vco 190. Oh, look at that.

That's a thing of beauty and a joy. forever. Beautiful. Somebody had fun there.

oh let's just you know, rotate them at the odd angle. There little bit of inductance, just, you know, snaking through on there. beautiful. And then the capacitors either side.
Ah, more funny business happening on that one. Check it out They decided. oh, let's put a little extra Loop up there I wonder what that does? Oh, check it out. You can practically see the waveform coming out of that thing.

So that folks is all she wrote on the tear down. unfortunately. I'd love to go into like you know details and do schematic like overlays of each block and stuff like that, but that would take all day. It really would or more.

Absolutely phenomenal. So I hope you enjoyed that. A big um, uh, thumbs up to uh the Agant RF division for sending this in for the tear down. They pretty gutsy I hope it goes back together H I Don't know, we'll see see anyway.

I'll reassemble the thing tomorrow and hopefully it will work. but that's it for the tear down. And if you want to, um, by all means, go through and like, uh, what some people have done for the previous ones, you know, go in and actually, uh, decode all the different blocks in there. but you know, um, geez, it's You know.

it's pretty complicated and you can see that each one has its own individual shielded you know, section components, both sides. Brilliant. We've got our voltage controlled oscillators, our local oscillators, our band pass filters, all sorts of RF Magic. And don't you just love the Uh filters on the PCB Absolutely brilliant I Love that.

but that's inside a uh $118,000 um, high-end Agilant handheld Spectrum analyzer. So huge thumbs up to the guys at Agilant for sending that through and if you want to discuss it, jump on over to the Eev blog Forum That's the place to do it. Catch you next time and.

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By YTB

20 thoughts on “Eevblog #470 – agilent n9344c 20ghz spectrum analyser teardown”
  1. Avataaar/Circle Created with python_avatars RBAD RBAD says:

    Thanks Dave!
    I have the N9340A HSA that I use for filter and duplexer tuning and general purpose work in public safety radio installation and maintenance. I paid a little over $2500 for it used on eBay. It’s definitely paid for itself in the 10 years or so that I’ve owned it. Great device.

    I love the fact that you allowed us an in-depth view INSIDE the N9344 series SA.
    This allowed me to avoid taking my SA apart and most probably destroying it just to see the inside magic of Agilent.

    Thanks for a phenomenal channel !

  2. Avataaar/Circle Created with python_avatars JouMxyzptlk says:

    Just re-watched this today, and I am still at total AW of that level of voodoo going on in there.

  3. Avataaar/Circle Created with python_avatars Florian Hofmann says:

    Given the low volume – are these boards all soldered by hand?

  4. Avataaar/Circle Created with python_avatars Pete Gas London says:

    "What's inside .." err.. Electric stuff 🙂

  5. Avataaar/Circle Created with python_avatars Jakob says:

    LOL where are the g0d dang video about the product..
    this is as stupid as it get..
    I will not test if the product is any good, I will only take it apart… because that is my saying-
    facep4lm.. its like looking at a cake and then analyzing what colors the cake has and what plate it is standing on.
    but actually tasting if its any good and how things work together and if its any good product / item.
    no no no..
    but this dude have like tons of channels.. so I don't know if he simply don't care, or put it somewhere else.
    it so basic things.. that you gotta wonder where his head is..
    If you didn't care to test if its a good product or you didn't had the time.. then tell so, and if there is a video actually testing this product then link it in… c'mon aussie bud.. it doesn't take a phd.

  6. Avataaar/Circle Created with python_avatars Travis says:

    the model # probably wasnt "pulled outta somebodies ass" each digit or digits probably represent different things

  7. Avataaar/Circle Created with python_avatars Travis says:

    …$18k…????

  8. Avataaar/Circle Created with python_avatars IndianTechSupport says:

    n9344c, do you wanna marry me?

  9. Avataaar/Circle Created with python_avatars Sirous Mohseni says:

    No wonder they offered you to take it apart. That design is so complicated, it is impossible to figure it out.

  10. Avataaar/Circle Created with python_avatars aeronauticsRc says:

    So i assume the 80+ghz instruments wil be inside molten lead? 😛

  11. Avataaar/Circle Created with python_avatars Techcafe says:

    Almost anyone can do teardowns, they seem to be very popular on YouTube these days. I must say, Dave, it does irk me that you "don't turn it ON" before taking it apart. Why not show us what the electronic equipment does and how it works, before you take it apart. It wouldn't add that much time or effort to your videos, would it? Cheers, from Canada.

  12. Avataaar/Circle Created with python_avatars Peter Sage says:

    Yo Dawg, we heard you like shielded cans. So we put cans inside your cans so you can can while you cancan.

  13. Avataaar/Circle Created with python_avatars Roll Bot says:

    the knife pucker factor across those RF traces is just…keeping me on edge!

  14. Avataaar/Circle Created with python_avatars uiop uiop says:

    when it opens the tátika (-tika)
    what is with you killa (killa)

  15. Avataaar/Circle Created with python_avatars Nodirbek Choriev says:

    I see that when you go 20Ghz you make your own passive components on pcb

  16. Avataaar/Circle Created with python_avatars Shant K says:

    Theme park for electrons.

  17. Avataaar/Circle Created with python_avatars laernulieNlaernulieNlaernulieN says:

    That's probably why it costs $18000, look at all the gold inside!

  18. Avataaar/Circle Created with python_avatars laernulieNlaernulieNlaernulieN says:

    I'm guessing the designing of the board probably takes a team of people months if not longer to finalize it ready for production

  19. Avataaar/Circle Created with python_avatars Puer Aeternus says:

    The holes are just for pressure equalization.

  20. Avataaar/Circle Created with python_avatars Werner Beroux says:

    I feel like discovering alien tech.

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