How well timed! My teardown of Linksys’ VLP01 router, submitted in late September, was revealed sooner or later prior to after I began engaged on this write-up in late October.

What’s the importance, except for the chronological cadence? Effectively, on the finish of that earlier piece, I wrote:

There’s one other shock ready within the wings, however I’ll save that for an additional teardown one other (near-future, I promise) day.

That day is at the moment. And when you’ve already learn my earlier piece (which you’ve got, proper?), you recognize that I really spent the primary few hundred phrases of it speaking a few totally different Linksys router, the LN1301, also called the MX4300:

I purchased a bunch of ‘em on closeout from Woot (yep, the identical place that the refurbished VLP01 two-pack got here from), and I even requested my spouse to select up one too, with the next rationale:

That’ll give me loads of items for each my present four-node mesh topology and as-needed spares…and finally I’ll determine to throw warning to the wind and redirect one of many spares to a (presumed damaging) teardown, too.

Final month’s greater brother

Maintain that thought. At this time’s teardown sufferer was one other refurbished Linksys router two-pack from Woot, bought a number of months later, this February to be actual. Woot promotion-titled the product web page as a “Linksys AX4200 Velop Mesh Wi-Fi 6 System”, and the specs additional indicated that it was a “Linksys MX8400-RM2 AX4200 Velop Mesh Wi-Fi 6 Router System 2-Pack”. It price me $19.99 plus tax (with free transport) after one other $5 promotion-code low cost, and I figured that, as with the two-VLP01 equipment, I’d tear down one of many two routers on your enjoyment and maintain onto the opposite to be used as a mesh node. Right here’s its inventory picture on Woot’s web site:

Seems to be kinda just like the MX4300, doesn’t it? I admittedly didn’t initially discover the bodily similarity, partially due to the MX8400 product title replicated on the outer field label:

Once I began engaged on the sticker holding the lid in place, I observed a nook of a bit of literature protruding, which turned out to be the guarantee brochure. Good packing job, Linksys!

Lifting the lid:

You’ll discover each routers inside, together with two Ethernet cable strands rattling round free. Beneath the thick blue cardstock piece labeled “Setup Information” to the best:

are the 2 energy provides, together with…umm…the setup information plus a assist doc:

Some pictures of the wall wart observe:

together with the specs:

and eventually, our affected person, as ordinary, accompanied by a 0.75″ (19.1 mm) diameter U.S. penny for measurement comparability functions. Entrance view:

left facet:

again, each an outline and a closeup of the varied connectors: energy, WAN, three LAN, and USB-A. Hmm…the place have I seen that combo earlier than?

proper facet:

high, full with the standing LED:

and…wait. What’s this?

A couple of option to “pores and skin a cat”

Along with the always-informative K7S-03580 FCC ID, try that MX4200C product title. Once I noticed it, I spotted two key issues:

• Linksys was taking part in an analogous naming recreation to what they’d completed with the VLP01. Quoting from my earlier teardown: “…an outer field shot of what I acquired…which, I’ve simply observed, claims that it’s an AC2400 configuration (I’m guessing it is because Linksys is mesh-adding the 2 units’ theoretical peak bandwidths collectively? Lame, Linksys, lame…)” This time, they seemingly added the numbers within the two MX4200 machine names collectively to provide you with the “greater is best” MX8400 moniker.
• The MX4200(C, on this case) is mighty near MX4300. Now additionally realizing the bodily similarity, I suspected I had a near-clone (and far cheaper, to not point out extra broadly obtainable) sibling to the no-longer-available router I’d mentioned a month earlier, which, being uncommon, I used to be due to this fact so reticent to (presumably destructively) disassemble.

Some background from my on-line analysis earlier than continuing:

• The MX4200 got here in two generational variations, each of them integrating 512 Mbytes of flash reminiscence for firmware storage. V1 of the MX4200 included 512 Mbytes of RAM and had dimensions of 18.5cm (7.3 inches) excessive and seven.9cm (3.1 inches) extensive. The bigger, 24.3cm (9.57 inches) excessive and 11cm (4.45 inches) extensive, V2 MX4200 additionally doubled the interior RAM capability to 1 GByte.
• This MX4200C is supposedly a Costco-only variant (which means what past the customized backside sticker? Dunno), conceptually harking back to the Walmart-only VLP01 I’d taken aside final month. I can’t discover any specs on it, however given its dimensional commonality with the V2 MX4200, I’ll be curious to look inside and see if it embeds 1 GByte of RAM, too.
• And the MX4300? It’s additionally dimensionally harking back to the V2 MX4200. However this time, there are 2 GBytes of RAM inside it. Final month, I’d talked about that the MX4300 additionally bumps up the flash reminiscence to 1 GByte, however the on-line supply I’d gotten that data from was apparently incorrect. It’s 512 GBytes, the identical as in each variations of the MX4200.

Diving in

Clearly, now that I’m conscious of the commonality between this MX4200C and the MX4300, I’m going to be extra cautious (however nonetheless complete) than I would in any other case be with my dissection, within the hope of a subsequent full resurrection. To wit, right here we go, following the identical preliminary steps I used for the a lot smaller VLP01 a month in the past. The one high groove I used to be in a position to punch via was the again edge, and even then, I needed to swap to a flat-head screwdriver to make tangible disassembly progress (with out completely creasing the spudger blade within the course of):

Voila:

Subsequent to go, once more as earlier than, are these 4 screws:

And now for a notable deviation from final month’s disassembly scheme. That point, there have been additionally screws below the underside rubber “toes” that wanted to be eliminated earlier than I may acquire entry to the insides. This time, conversely, after I picked up the meeting in preparation for turning it upside-down…

Alrighty, then!

Behold our first glimpses of the insides. Referencing the sooner outer case equivalents (with the qualifier that, visually clearly, the PCB is put in diagonally), right here’s the entrance:

Left facet:

Again, together with one other accompanying connectors closeup (observe, by the best way, the 2 screws on the backside of the uncovered portion of the PCB):

And proper facet:

Let’s subsequent do away with the plastic defend across the connectors, which, as was the case final month, lifted away straightaway:

Warmth-removal {hardware} removing

And subsequent, the finned heatsink to its left (within the earlier picture) and the rear proper half of the assemblage (when considered from the entrance):

We have now liftoff:

Oh, goodie, Faraday cages! Maintain that thought:

Rotating the assemblage round exposes the opposite (entrance left) half and its steel plate, which, with the just-seen 4 heatsink screws additionally now not holding it in place, lifts proper off as effectively:

You in all probability already observed the coloured wires within the prior pictures. Listed below are the up-top antennas and LED meeting the place they find yourself:

And right here’s the place at the very least a few of them originate:

Unhooking the wire harness operating up the facet of the assemblage, together with eradicating the 2 screws famous earlier on the backside of the PCB, allows the board’s subsequent launch:

Right here’s what I’m calling the PCB bottom (previously within the rear proper area) which the finned heatsink beforehand partially coated and which you’ve already seen:

And right here’s the newly-exposed-to-view frontside (previously entrance left, to be exact), with even extra Faraday cages awaiting my pry-off consideration:

Dissecting cage contents

I’m comfortable to oblige. Higher left nook first:

Quickly (as a result of, as beforehand talked about, I aspire to place all the things again collectively in functionally resurrected kind later) bend the tab away, and with due to Google Picture search outcomes for the tip, a Silicon Labs EFR32MG21 Collection 2 Multiprotocol Wi-fi SoC, supporting Bluetooth, Thread, and Zigbee mesh protocols, comes into view. The beforehand proven single-lead antenna connection on the opposite facet of the PCB is presumably related to it:

To its left, uncaged, is a Fidelix FMND4G08S3J-ID 512 Mbyte NAND flash reminiscence, presumably for holding the system firmware.

Many of the remainder of the cages’ contents are bland, except you’re into plenty of passives; as you’ll quickly see, their related ICs on the opposite facet are extra thrilling:

Notice in all these so-far instances, in addition to the rest, that thermal tape is employed for warmth switch functions, not paste. Linksys’ resolution not solely makes it simpler to see what’s beneath it can additionally enhance the next chance of tape-back-in-place reassembly practical success:

And in spite of everything these passives, the ultimate cage at backside left ended up being IC-inclusive once more, this time containing a Qualcomm PMP8074 energy administration controller:

Now for a revisit of the opposite facet of the PCB, beginning with the top-most cage and dealing our option to the underside. The primary one, with two antenna connectors notably above it, encompasses a portion of the wi-fi networking subsystem and is predicated on two Qualcomm Wi-Fi SoCs, the QCN5024 for two.4 GHz and QCN5054 for five GHz. Above the previous are two Skyworks SKY85340-11 front-end modules (FEMs); the latter is topped off by two Skyworks SKY85755-11s:

C = Costco = capacity-reduced?

The subsequent cage is for the processor, a quad-core 1.4 GHz Qualcomm IPQ8174, the identical SoC and velocity bin as within the Linksys MX4300 I mentioned final month, and the unstable reminiscence, two ESMT M15T2G16128A 2 Gbit DDR3-933 SDRAMs. I assume we now understand how the MX4200C differs from the V2 MX4200; Linksys halved the RAM to 512 GBytes whole, harking back to the V1 MX4200’s allocation, to provide you with this Costco-special product spin.

The third one, this time with 4 antennae connectors under it, homes the rest of the (5 GHz-only, on this case) Wi-Fi subsystem; 4 extra Qualcomm QCN5054s, every with a mated Skyworks SKY85755-11 FEM:

And final however not least, at backside proper is the ultimate cage, containing a Qualcomm QCA8075 five-port 10/100/1000 Mbps Ethernet transceiver, solely 4 ports’ price of that are seemingly leveraged on this design (one WAN, three LAN, when you’ll recall from earlier). Its perform is unsurprising given its format proximity to the 2 Botthand LG2P109RN dual-port magnetic transformers to its proper:

And with that, I’ll wrap up for at the moment. Extra data on the MX4200 (V1, to be exact) could be discovered at WikiDevi. Over to you on your ideas within the feedback!

—Brian Dipert is the Principal at Sierra Media and a former technical editor at EDN Journal, the place he nonetheless usually contributes as a freelancer.

Associated Content material

• A contemporary gander at a mesh router
• The professionals and cons of mesh networking
• Teardown: The router that took down my wi-fi community
• Is it time to improve to mesh networking?

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