I'm imagining a "stealth" wifi controller on one of the custom chips, hung onto a pin connected to an internal antenna realized on an internal copper layer of the motherboard. If you used a non-standard frequency and protocol, who would know?<p>You could probably get an okay transmit-only signal with fairly unremarkable on-chip hardware (say, a simple PCM) and something that didn't look <i>too</i> much like an antenna even if you X-ray'd the board. I'm guessing that a similarly stealthy receiver would be noticeable due to required external discrete components (e.g., amplifiers, filter networks).<p>Plonking down a whole chip for "secret wifi" is likely overkill.
<i>We’re not sure exactly what the technicians did to remove the chip – heat gun, maybe? – but it came off cleanly and you wouldn’t notice it was missing unless you were specifically looking for it on the board.</i><p>Almost certainly, or more precisely, a "hot air rework station". For someone with experience, it only takes a few minutes to remove and replace BGAs with one.
This story made me realize: I haven't seen the phrase "tin-foil hat" used much in the past couple of years. Huh.<p>Which reminded me of a quote:<p>"For a while you wondered whether the fools were pretending to be fools as some kind of deception, or whether there was a real efficient service somewhere else. Later in my fiction, I invented one. But alas the reality was the mediocrity." — Le Carre
In Apple's computers the web cam light cannot be disabled, because the web cam is controlled by a co-processor as demoed here. In the newer Pros with Touchbar Apple uses their own chip for this same function.<p>On a lot of PC webcams, you can run the camera without the light or visa versa[0].<p>[0] <a href="https://blog.erratasec.com/2013/12/how-to-disable-webcam-light-on-windows.html" rel="nofollow">https://blog.erratasec.com/2013/12/how-to-disable-webcam-lig...</a>
> This sounded reasonable, so I ventured to the streets of New York City to seek the help of some professionals!<p>If the author of the article is here - I'd suggest turning to Louis Rossmann of YouTube fame:<p><a href="https://www.rossmanngroup.com/" rel="nofollow">https://www.rossmanngroup.com/</a><p><a href="https://www.youtube.com/user/rossmanngroup" rel="nofollow">https://www.youtube.com/user/rossmanngroup</a><p>He has the equipment and skill to repair a logic board, and may have some valuable insights about failure modes of common chips on MacBooks.
uhhh...how does this prove that the chip doesn't have radio functionality? they didn't figure out any information about the chip's actual functionality beyond its PCI device name, which would ostensibly not be "SUPER SECRET DATA EXFILTRATION RADIO FOR NSA". they just took it off, unplugged the wifi card, and then said "well, it doesn't connect to wifi networks now. must be fine".
If you really need an air gapped computer, wouldn't it make a whole lot more sense to build a desktop with some variety of ATX form factor motherboard that you can examine in detail to confirm that it has zero wireless functionality?<p>A Macbook Air, which is pretty much designed as a wifi-dependent network terminal, would be way down my list of hardware I would choose if I had to build an airgap lab environment.
If you do some search you can find logic boards PCB layouts and electronic schematics on internet.<p>Here is a link: <a href="https://www.apple-schematic.se/" rel="nofollow">https://www.apple-schematic.se/</a><p>Edit: And to look at the PCB files I recommend <a href="https://openboardview.org/" rel="nofollow">https://openboardview.org/</a>