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Comment by tyingq | Hacker News Reader

A similar thing happened in the US military. There used to be a system where voice, radar info, and data were relayed back from the front lines of a conflict via a system of portable microwave stations.

Some of them short (<~50 miles) links with horn antennas like you see in this article. Longer links with parabolic dishes and tropospheric scatter. All "portable" equipment on camouflaged trucks and trailers that could be unloaded and assembled anywhere.

All of that started being replaced in the mid-90's with a combination of dedicated military satellite equipment and more use of commodity stuff like small commercial microwave network bridges, cellular phones, satellite phones, and so on. They closed out the "microwave tech" jobs and folded them in with "satcom" or other specialties.

Some of the equipment:

https://en.wikipedia.org/wiki/AN/TRC-97

https://www.marines.mil/Photos/igphoto/2001740716/ (apparently still used by the Marine Corps)

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> A similar thing happened in the US military

I'm not saying you're incorrect that the military had similar tech to what AT&T had, but I'll split the hair that they actually worked together hand-in-hand.

They actually populated AT&T Long Lines towers with AUTOVON equipment which was the old military phone system in the US. Also used the same switching network to support Air Force One with the Echo Fox Presidential Aircraft network. Some of the locations were hardened for nuclear attack.

https://en.wikipedia.org/wiki/Autovon

http://www.coldwar-c4i.net/Echo-Fox/index.html

That may be true for some equipment in the miltary. The ones I'm talking about were standalone and portable, for use in a war zone. The only connections they would make to non-military equipment was after the voice/data was de-muxed into channels. That could be connected to phone lines, etc. Typically, though, pretty far downstream after passing through different equipment.

In response to a post about the AT&T Long Lines network, saying something "similar" happened in the military seems disingenuous because they were absolutely partnered on the same project. To imply something is "similar" typically implies that it is separate to some degree - that's not the case with AT&T and the US military in regards to the Long Lines Network.

Sorry, that just makes no sense to me. I'm talking about mobile military equipment that talked microwave only to other mobile military equipment. Equipment that would be deployed in a war zone, where AT&T probably wasn't present. Like a connection between a forward air control post and a rear echelon camp. Both being (typically) a bunch of tents and vehicles in the middle of nowhere. Downstream from that was voice/data channels that wouldn't care what AT&T or anyone else was doing.

You seem to be talking about military use of FIXED (not portable/tactical) microwave, which is a different space.

> You seem to be talking about military use of FIXED (not portable/tactical) microwave, which is a different space.

Which is what the original post/article was about - the fixed terrestrial microwave network that AT&T ran... which was a major joint effort with the US military.

Sorry I got caught up on "similar" being confusing when the military was 100% involved with what the original post was discussing (specifically the AT&T Long Lines network) - I regret my comments.

Folkhack, You’re simply wrong. Stop arguing when you don’t possess firsthand knowledge.

(I see you’ve added a new culpa, no worries! We all learn new stuff)

Wanna go down a rabbit hole? Remember that spectrum sale in the 2010s? What if I told you the FBI had their own microwave network that they divested of around that time?

Interesting stuff!

> You’re simply wrong

Specifically - what am I wrong about? As-per HN guidelines specify exactly what I have said that is factually incorrect? Please quote it directly if you can, and in good faith provide sources so I can better inform myself.

I simply disagree that I'm wrong about anything that I've stated here - I have specifically visited a Long Lines AUTOVON switching site; 100% the US military was partnered with AT&T for this. I actually possess first-hand knowledge on this - I've met with site owners.

> I see you’ve added a new culpa, no worries! We all learn new stuff

OK? Honestly I was just trying to be polite and it was less of an apology and more taking the passive road out when we were obviously talking about two separate things. I don't disagree with anything that tyingq was saying - I was just trying to make a nuanced point regarding the partnership between AT&T and the US Military which is directly related to the article that was originally posted. Somewhere wires got crossed and I just decided to bow out as politely as I could.

Sometimes socializing on this site really weirds me out. Please, in good faith: what have I factually said that is incorrect here?

No prob! Specifically this: “To imply something is "similar" typically implies that it is separate to some degree” So the US military has many microwave comm projects. ATT was only one of them that was left unused. Many had no ATT involvement whatsoever. So yeah, military had contracts with ATT, but those were a tiny subset of microwave efforts.

Former Submarine communications specialist here.

I'm being misunderstood, I'm going try to to explain better.

I literally opened my original response to tyingq with "I'm not saying you're incorrect" as I did not want to invalidate anything they had written. I was not trying to argue a single point. I just found the grammar/set theory of "A similar thing happened in the US military" odd when that specific thing (the Long Lines microwave network) happened in the US military in a big way.

On your newly introduced point: "military had contracts with AT&T, but those were a tiny subset of microwave efforts". I do not describe the backbone of AUTOVON as a "tiny subset" of anything... The AT&T Long Lines was an engineering marvel. The achievement to reliably transmit coast to coast audio, video, and data through hundreds of redundant radio/switching sites was huge - that simply did not exist before. AT&T Long Lines is very significant to the history of microwave communications in the military specifically through AUTOVON.

I'm absolutely not arguing against the existence of military microwave tech independent of AT&T - I feel like this is obvious, but I also feel I have to state it outright after reading your comment.

Thank you for taking the time to explain your thinking to me. Sometimes I can be thickheaded!

There's a bit of both going on, the military did make use of some portable equipment developed by Bell System family companies including WECo. But for the most part, military transportable equipment into the cold war was made by RCA. RCA was more of a "manufacture for sale" type operation than AT&T and had more expertise in portable equipment.

Of course, AT&T was one of the founders of RCA, but by the time microwave and troposcatter were coming into use AT&T had sold their shares. Nonetheless there was plenty of technical interchange between AT&T and RCA during that period, and some of the RCA equipment for the military was based on Bell Laboratories and WECo work.

The military often made practical decisions of whether it was better to field themselves or contract - and so military connectivity was sometimes contracted to AT&T even in surprising situations like overseas. But field-deployable portable systems have always been impractical to contract out and so the military tends to keep its own assets.

Other parts of the government took this other directions. The State Department nearly exclusively contracted to AT&T including for foreign installations. The FAA did so surprisingly infrequently, maintaining its own expansive microwave network until just recently.

Army 25P (microwave systems MOS) is still around iirc (at least in the Reserves), and speaking from personal experience, 25Q10EAC was still getting dedicated 10 week training on tropo and DGM enclosures in 2012 at AIT.

That EAC rider was certainly rare, but we were told tropo was still in play in South Korea, and as late as 2015, another company in my reserve ESB had a few tropo systems they were still maintaining and training on.

But yes, by and large, most microwave-based signal MOS were rolled into either point-to-point "multichannel transmissions" (25Q) by which a good part of your qualifications include deployment of satellite transportable trailers (STT), SMART/T systems (shared with the Marines),and the Phoenix system; and the dedicated SATCOM MOS (25S).

as a former 25U and 25A i've heard stories of what happened to birds that landed on that tropo ::shudder::

I was one of those techs, 29m

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