14 ms·

AT&T’s Abandoned Microwave Tower Network (2017)

225 points by ecliptik 5y ago

psim1 5y ago
I used to live next to one of these! It was a useful landmark: turn right at the tower. There was also an underground bunker next to it that someone bought in recent years and attempted to make into living quarters.
JCM9 5y ago
Many small towns still have these telephone microwave towers around if you know what to look for.
- Zigurd 5y ago
  The AT&T Long Lines network predates the use of digital radio for telecommunications. It used analog FDM to carry multiple calls. These towers have lasted because they, and the radio equipment, were designed to survive a nuclear war. (Another reason the fiber transition happened quickly was that fiber was more survivable.) There are many new microwave links being deployed now using modulation techniques for digital data.
- throwawayboise 5y ago
  There is one along the road on my way to work. It's still used, but the microwave horn antennas have been replaced by cellular network antennas.
- embedded_hiker 5y ago
  Here is a site in downtown Portland OR: https://www.google.com/maps/@45.5230331,-122.6802471,3a,75y,124.74h,121.75t/data=!3m6!1e1!3m4!1snRk3DMvLa-7RI74trqqtbw!2e0!7i13312!8i6656 https://www.google.com/maps/@45.5230331,-122.6802471,3a,75y,...
- pixl97 5y ago
  Where I used to live in East Texas there was one of these, well, at least a few decades ago. Never knew exactly what it was for. But it is a mirror image of the pictures. The things you learn later in life because of the internet.
- flyinghamster 5y ago
  Cell carriers often use microwave backhaul as well, particularly when fiber infrastructure is unavailable. These are usually smaller dishes mounted on cell towers, rather than big horn antennas.
- __turbobrew__ 5y ago
  There is one in Vancouver BC. I always wondered what is is: https://goo.gl/maps/RKVvfiDApVxCWsnj7 https://goo.gl/maps/RKVvfiDApVxCWsnj7
  - walrus01 5y ago
    The Telus CO downtown at Robson and Seymour used to have a large tower on the roof with 6GHz horns, linked to that site, and towards the site on Bowen Island which still has horns. Bowen Island was a link to the sunshine coast, across to Nanaimo, and many other places. There is also a big site out in the fraser valley on a hilltop that was part of the long lines network with shots going east towards Hope (trans canada microwave) and down into Whatco County.
    - __turbobrew__ 5y ago
      Interesting! Thank you for the information. Does the trans Canada microwave go along the coquilhalla highway? I notice that there are point to point links along the side of the highway. Were the microwave links to Nanaimo and the Sunshine Coast replaced by fiber?
      - walrus01 5y ago
        There's submarine fiber to Vancouver island now, in a diverse ring, so yes. Still is some microwave operational on sunshine coast but not as a primary thing. Big parts of trans Canada microwave have now been dismantled. There was a mountain top site slightly NE of Hope that could only be reached by its own cable car. And lots of other mountain top sites east of it going all the way to Lethbridge.
ugjka 5y ago
Also known as bird killers
themodelplumber 5y ago
That's a great resource, thank you. I learned just a little about these after making the decision that my drives through Nevada would never again be boring. Once I started asking questions about what I was seeing, the "ice cream cones" or horn antennas really did stand out in a fascinating way. And $25K to buy one does seem like it could be a terrific deal in the right situation. Another thing I asked about: When I stopped to get gas or groceries, I realized there were tall visibility flags on the back of so many Nevadan trucks, even what looked like personal vehicles. I had overlooked them for years. An interesting dive into an industry and its culture started there. BTW, speaking of old towers that went up for sale and are possibly interesting to ham radio operators: Here's one near me (NorCal Bay Area) that was purchased by a local bay leaf grower and then opened for ham radio use--in exchange for a refurbishment effort. https://www.youtube.com/watch?v=GMtkLjHUgYU https://www.youtube.com/watch?v=GMtkLjHUgYU
- deleted 5y ago
  [deleted]
- bombcar 5y ago
  What are the flags for?
  - dmd 5y ago
    http://www.miningwhips.com/ http://www.miningwhips.com/
    - themodelplumber 5y ago
      Yep, this.
    - nitrogen 5y ago
      They are also for off-road recreational use, e.g. in sand dunes.
- ashleyn 5y ago
  Growing up in the mountains, I remember seeing a curious kind of antenna up on a mountain nearby. It didn't look like the others; from one angle it looked like a three-petal flower and across town, it looked like a giant robot with two antennae. Wondered what it was for years since it looked so unusual. Only a few years ago I learned it was a long-decommissioned AT&T Long Lines tower: an urban explorer had filmed it. https://youtube.com/watch?v=MvXxNheLATw https://youtube.com/watch?v=MvXxNheLATw
mbostleman 5y ago
Any reason AT&T isn't removing and disposing of these towers?
- astronautjones 5y ago
  most of them are just on top of mountains or hills http://long-lines.net/places-routes/index.html http://long-lines.net/places-routes/index.html
- grendelt 5y ago
  Cost. Several of them are hosting cell and radio services so that "pays the rent" on the location. Dismantling and scrapping such a tower would be enormously expensive and bring no value to AT&T shareholders. If they're in total disrepair, I'm sure a case can be made for safety in an urban area. The two towers closest to me are in rural areas with several other radio service tenants where maintenance is a covered cost.
  - Aloha 5y ago
    Legacy AT&T owns almost none of them anymore, what's left are owned by the RBOC (often the other AT&T) and as you note, have a prohibitive removal cost and are in urban centers.
- aasasd 5y ago
  I'm gonna guess that spending money on that seems a highly dubious investment.
  - mistrial9 5y ago
    safety and clean-up are always a cost center, on the books.
  - dboreham 5y ago
    Almost all the sites are still in use due to the resurgence in terrestrial wireless use in the past 20 years.
- 5y ago
aasasd 5y ago
> Built in the early 1950s... It conveyed phone conversations and television signals from the era of the Kennedy assassination through the resignation of Nixon Even from the other side of the globe I can tell that it seems strangely short-lived. Built for a decade, then used for a decade? Wikipedia notes tersely: > The launch of communication satellites in the 1970s provided a cheaper alternative.
- magila 5y ago
  Technology advanced extremely quickly from the 40s to the 70s. Much of what was built in that time became obsolete soon after it was completed.
- weird-eye-issue 5y ago
  Just wait until you hear about smartphones
  - nine_k 5y ago
    Less of a joke than one might think. The GSM / 2G / 3G / 4G / 5G transition took less than 30 years, each step involved scrapping some of the old incapable hardware.
- allturtles 5y ago
  I think this is wrong. AFAIK satellites have never been a significant channel for domestic phone calls. Microwave relays were obsoleted by fiber optics.
  - alrs 5y ago
    > Like their predecessor satellites, the Telstar 3 satellites operate at 6/4 GHz (C band). Simultaneous long distance telephone call capacity is 21,600. The satellites furnish voice, video, and high speed data services. https://www.telcomhistory.org/resources/online-exhibits/science-of-phones/calling-a-country-far-away/ https://www.telcomhistory.org/resources/online-exhibits/scie...
dunham 5y ago
My dad used to work on these towers in the midwest. Back in the day, he told me that they still had plenty of capacity, but AT&T had to switch to fiber after Sprint "dropped the pin".
sgt101 5y ago
BT built a system of underground copper pipes/waveguides for microwave transmission in the 1970's - it never got beyond a testing platform in Suffolk (Martlesham Heath to Wickham Market) due to fibre optics becoming the clear winner.
- Aloha 5y ago
  AT&T built one as well, the WT4/WT4A system. https://archive.org/details/bstj56-10-1829 https://archive.org/details/bstj56-10-1829
- walshemj 5y ago
  And some above ground waveguides alongside a main road near Ipswich - not sure if they are still there.
  - superkuh 5y ago
    There's some cool but not very ready tech called surface wave transmission lines that use horn like "launchers" to establish surface waves on single conductors like power lines. They have very low RF losses up to the tens of GHz as long as stuff stays a few wavelengths away from the lines. In way, if you try hard enough, most powerlines could act like inside out waveguides for high data rate RF backhaul.
  - sgt101 5y ago
    There is a story that the "Radio Tower" at BT Labs was built as a waveguide - this is on the A1214. Given that the office accomodation in it is so weirdly laid out I can believe that this might be so.
kzrdude 5y ago
Interesting. Is there no corresponding podcast episode for this story?
tyingq 5y ago
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://en.wikipedia.org/wiki/AN/TRC-97 https://www.marines.mil/Photos/igphoto/2001740716/ https://www.marines.mil/Photos/igphoto/2001740716/ (apparently still used by the Marine Corps)
- ms4720 5y ago
  I was one of those techs, 29m
- peterangular 5y ago
  > 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 https://en.wikipedia.org/wiki/Autovon http://www.coldwar-c4i.net/Echo-Fox/index.html http://www.coldwar-c4i.net/Echo-Fox/index.html
  - tyingq 5y ago
    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.
spacecadet 5y ago
My family leases land in Maine for one of these towers. They are still maintained.
cenazoic 5y ago
The Qwest Tower building in Minneapolis referenced in the article has been the CenturyLink Building since 2011, and the microwave was removed in 2019: ref: https://www.startribune.com/after-50-plus-years-the-centurylink-building-in-mpls-sheds-its-crown/561882801 https://www.startribune.com/after-50-plus-years-the-centuryl...
- rsync 5y ago
  ... and is the most beautiful Central Office (CO) building in the United States.
retrac 5y ago
I think this fits the mood. The old telephone system was entirely analogue. It remained so well into the 1980s, even when they were carrying tens of thousands of conversations in parallel on a single wire or antenna. When I was a kid, you could hear the white noise stack successively louder on a long-distance call, as it went through each additional link. And sometimes you could hear the hum of it all, just below the threshold of intelligibility. In hindsight it's amazing how well it all worked. But sometimes it didn't work so well: https://vocaroo.com/1oCxkWyNDusp https://vocaroo.com/1oCxkWyNDusp Maybe a filter was slightly out of tune on that day. Recorded mid-1970s New York. The electronic beeps are in-band call establishment tones. (Yes, the same ones phone phreaks exploited. The recording was in fact made by one of those phreaks who has gone back and narrated some of his old recordings http://www.evan-doorbell.com/ http://www.evan-doorbell.com/ )
- deleted 5y ago
  [deleted]
- jibcage 5y ago
  “Hello? Yes, a collect call for Mrs. Floyd from Mister Floyd Will you accept the charges from United States?” I always wondered what those beeping tones were in the recording at the end of that song (“Young Lust”). I guess I’m not old enough :)
  - TedDoesntTalk 5y ago
    Those are in-band signals to the switching equipment. The equipment would “hear” those tones and translate them into “machine instructions”. That’s why phreakers could exploit the system by generating those tones themselves and playing them into the phone microphone.
    - jeffrallen 5y ago
      That's why you do not control networks with signals on the network itself. See also: Facebook's recent outage.
diskzero 5y ago
I lived directly across the street from one of the "Long Lines" towers on Queen Anne Hill in Seattle, WA. [1] It was actively maintained, with various antenna arrays being attached or removed frequently. The building below was packed full of gear and service vans were coming and going all the time. I was sorely tempted to try and climb it over the various years I lived in Seattle, but decided it wasn't worth either the arrest or death by electrocution or ground impact! 1. https://www.google.com/maps/place/315+W+Galer+St,+Seattle,+WA+98119/@47.6323144,-122.3615366,3a,75y,357.71h,110.22t/data=!3m6!1e1!3m4!1sy4UHRwaLuVpqtauIrxZ3iQ!2e0!7i16384!8i8192!4m5!3m4!1s0x5490156b89f8ab9f:0x2b7e34054bd175e7!8m2!3d47.6321641!4d-122.3611876 https://www.google.com/maps/place/315+W+Galer+St,+Seattle,+W...
- walrus01 5y ago
  the queen anne site is a wireline CO for that region, and has cellular stuff on it. The 6 GHz microwave has been out of service for many years. It used to be a primary link across the sound, to things in Kitsap, and similar. fairly typical USWest/Qwest central office otherwise.
Goety 5y ago
A lot of broken links in that article
ipdashc 5y ago
Love seeing these get brought up. It's a really fascinating system from an era when communications infrastructure was a bit more visible. It's one of those things where, once you learn it exists, you'll start seeing them (the towers/horns) popping up all over the place. My favorite AT&T artifact, though, has gotta be the Project Offices: https://en.wikipedia.org/wiki/Project_Offices https://en.wikipedia.org/wiki/Project_Offices The gist of it seems to be that these are secure, physically guarded, literal underground bunkers built into the tops of mountains along the East Coast, housing troposcatter antennas and satellite dishes. Super cool. As far as I can tell, nobody ever truly figured out exactly what they're for, and most are still operational today. I tried driving up to one once, out of curiosity, and there are some pretty intimidating "stay out of here" signs and cameras, even at the very base of the mountain. Chances are they were simply just meant for the military AUTOVON network, mentioned near the top of this thread. But I suppose that doesn't explain why they're still operational nowadays. https://coldwar-c4i.net/ATT_Project/index.html https://coldwar-c4i.net/ATT_Project/index.html (Funny enough, this website is maintained by the same Albert LaFrance who runs long-lines.net, mentioned in the article) https://coldwar-c4i.net/ATT_Project/VA01/ATTsiteB.html https://coldwar-c4i.net/ATT_Project/VA01/ATTsiteB.html This one is actually decommissioned and has pictures of the inside: https://coldwar-c4i.net/ATT_Project/Buckingham/index.html https://coldwar-c4i.net/ATT_Project/Buckingham/index.html Super interesting stuff, IMO
- deleted 5y ago
  [deleted]
- js2 5y ago
  Wild. I've lived 30 minutes from the one in Chatham for 15 years and never heard of it before. https://www.flickr.com/photos/legeros/albums/72157691603482592 https://www.flickr.com/photos/legeros/albums/721576916034825... http://www.thetownofliberty.com/2018/01/the-mystery-of-big-hole-road-in-chatham.html http://www.thetownofliberty.com/2018/01/the-mystery-of-big-h...
  - ipdashc 5y ago
    Yeah they're crazy. Super obscure bits of infrastructure and Cold War history. It's interesting to me how all the signs in that Flickr album say "People" instead of "Personnel" (Delivery People, Authorized People Only). Was this an AT&T thing?
EGreg 5y ago
Does AT&T still send you microcells?
genocidicbunny 5y ago
How serendipitous, I was just watching a show Bob Moses [1] did on one of these towers above LA, and was wondering what they were. Now I've my answer. 1. https://www.youtube.com/watch?v=xKeduffv7_U https://www.youtube.com/watch?v=xKeduffv7_U
NelsonMinar 5y ago
We've got networks like this all over rural America. Only instead of giant towers they're little consumer fixed wireless nodes, getting 1-25Mbps (or more!) via 2.4GHz. 5GHz if you're lucky.
mtippett 5y ago
I had just moved to Toronto in about 2002, and was waiting for an interview. I saw one of those microwave horns on a building in the distance. Puzzling over what it was. Interview started, talking about something glanced over the background and muttered verbally "Microwave" as it hit me that it was a microwave waveguide of some sort. Didn't get the job...
- walrus01 5y ago
  The entire lower white donut ring around the bottom of the CN tower is a radome, inside are ptp microwave dishes. It was a lot more relevant in the era before singlemode fiber went everywhere. Looks like this inside. https://www.jagelectromagnetics.com/images/jag_cataloug_images/JAG_Catalogues_CN_Tower.jpg https://www.jagelectromagnetics.com/images/jag_cataloug_imag... Nowadays there is some 2.0GHz band ENG stuff up there for live news gathering stand ups.
ksec 5y ago
Why is the Title Edited ? >Vintage Skynet: AT&T’s Abandoned “Long Lines” Microwave Tower Network The original title of the article, actually make sense in the subject of "Long Lines". But the submitted title make it sounds like AT&T totally abandoned Microwave Network. I dont know about AT&T but Microwave Network is still actively being used today and refined even in the latest 5G 3GPP Spec Rel 16, 17 and 18. Other than that it is a nice piece and history of the system.
- walrus01 5y ago
  PTP microwave is very much in use by many carriers, it's absolutely essential for a lot of modern cellular network builds. But the actual microwave horn antennas in the 6 GHz band, that typified the inter-city AT&T long lines network, are 98% decommed in place these days. You would be very hard pressed to find a site that still has the waveguide, waveguide pressurization system, and a live FCC part 101 licensed 6 GHz radio running on a horn-to-horn path.
gpvos 5y ago
Of course, many countries have had a similar network. I like the towers of the Netherlands, which have similar designs to each other, even though each is unique. A few have a radio mast on top. Click the links at the bottom of https://cellnextelecom.nl/over-cellnex/locaties/ https://cellnextelecom.nl/over-cellnex/locaties/ to get an impression. Currently they are mostly used as data centres, but I think they still provide some microwave links as well.
rsync 5y ago
If you spend any time in the mountains you will see "blank" billboards up in the hills. These are "passive repeaters"[1] for microwave networks and I am surprised they weren't mentioned in the article ... [1] https://en.wikipedia.org/wiki/Passive_repeater https://en.wikipedia.org/wiki/Passive_repeater
- walrus01 5y ago
  Here's a 1984 vintage PDF for passive microwave repeater engineering: https://az276019.vo.msecnd.net/valmontstaging/vsna-resources/microflect-passive-repeater-catalog.pdf?sfvrsn=6 https://az276019.vo.msecnd.net/valmontstaging/vsna-resources... For the most part these are almost obsolete, the typical data link that many of them carried was one DS3, or at most, three DS3... The path loss is extreme. Usual setup was to go from a small town central office (CO), 3-5 km up to a nearby mountain, then bounce it off there, and 25-30 km to another nearby mountain. With big old power hungry PTP microwave gear that occupied a full 42U rack, took 1200W of power, and carried a whole lot of DS0. Nowadays a modern PTP microwave radio that can carry 1400Mbps full duplex in the 6 or 11 GHz bands is as little as 35W of power, so many hilltop tower sites either have built electrical grid connections, off grid solar, or whatever. Building some of those passive repeater billboards in places with no road access was very costly. Big helicopter bills and very labor intensive. You can still see a number of them on hillsides in eastern Oregon.
  - jonah-archive 5y ago
    Spotted one up on Steens Mountain not so long ago: https://www.google.com/maps/@42.4584052,-118.6942825,155m/data=!3m1!1e3 https://www.google.com/maps/@42.4584052,-118.6942825,155m/da...
- jcrawfordor 5y ago
  Passive repeaters were certainly not common, possibly not used at all in the AT&T Long Lines network. I am not aware of any examples at least. In general AT&T did not like them, it's more common for telephone passive repeaters to have been installed by CLECs or telephone cooperatives, and later on I know MCI used some in this area. These were all later installations than most Long Lines. I'm not sure exactly why AT&T eschewed them besides the speculation that AT&T built much of their microwave network relatively early and so the attenuation may not have been acceptable given the already short range on their links. AT&T's first generation of microwave sites had to put the RF amplifier in a hut on top of the tower because the waveguide loss was unacceptable, for example. A very common place to find passive repeaters in the desert west is at dams, where they were almost invariably installed to provide the telephone connections to the power house. A later interesting example of passive reflectors is the "periscope antenna," mostly used by Western Union when they operated a microwave network for a time. The actual microwave antennas were mounted on the roof of the shack pointed up, and at the top of the tower passive reflectors at a 45 degree angle "bent" it to horizontal. It put the more maintenance intensive parts on the ground at the cost of some power loss.
bogomipz 5y ago
Also worth mentioning that MCI, an AT&T competitor and thorn in their side, also had a microwave relay network. The M in MCI is for microwave. There's some great info on MCI here: https://telephoneworld.org/long-distance-companies/the-history-of-mci/ https://telephoneworld.org/long-distance-companies/the-histo... For those not familiar MCI was a real innovator and an important part of internet history. Vincent Cerf, an internet giant, worked for MCI[1]. Sadly MCI was relegated to the dustbin of history as a result of the WorldCom scandal[2]. They are sadly just a part of Verizon Business today. [1] https://en.wikipedia.org/wiki/Vint_Cerf https://en.wikipedia.org/wiki/Vint_Cerf [2] https://en.wikipedia.org/wiki/WorldCom_scandal https://en.wikipedia.org/wiki/WorldCom_scandal
Goety 5y ago
I kind of want one but i dont think any are still for sale.
razzmataz 5y ago
I used to live in an area served by what was then GTE and they had antennas like this. I have not seen anything listing GTE’s equivalent infrastructure. Does anything exist for that?
dhosek 5y ago
Alas, the linked google maps link for the towers is now 404'd. I was curious to look closer to see if any of the towers near me still existed.
- dhosek 5y ago
  Ah, but I've turned up this rather comprehensive site: https://long-lines.net/places-routes/ https://long-lines.net/places-routes/
xyzzy21 5y ago
Fun fact: the USSR used exactly the same technology and that is why enabled the US to monitor all phone calls using the Rhyolite/Aquacade surveillance satellite: microwaves are line-of-sight and due to the curvature of the Earth (take that flat-Earthers!), the inter-station signals continue into space and are receivable by a big enough antenna. https://en.wikipedia.org/wiki/Aquacade_(satellite) https://en.wikipedia.org/wiki/Aquacade_(satellite) Fun fact 2: back in the day you could make a "station-to-station" long distance calls - these are the "stations" they were talking about.

225 points by ecliptik 5y ago

I used to live next to one of these! It was a useful landmark: turn right at the tower. There was also an underground bunker next to it that someone bought in recent years and attempted to make into living quarters.

JCM9 5y ago

Many small towns still have these telephone microwave towers around if you know what to look for.

Zigurd 5y ago
The AT&T Long Lines network predates the use of digital radio for telecommunications. It used analog FDM to carry multiple calls. These towers have lasted because they, and the radio equipment, were designed to survive a nuclear war. (Another reason the fiber transition happened quickly was that fiber was more survivable.) There are many new microwave links being deployed now using modulation techniques for digital data.
throwawayboise 5y ago
There is one along the road on my way to work. It's still used, but the microwave horn antennas have been replaced by cellular network antennas.
embedded_hiker 5y ago
Here is a site in downtown Portland OR: https://www.google.com/maps/@45.5230331,-122.6802471,3a,75y,124.74h,121.75t/data=!3m6!1e1!3m4!1snRk3DMvLa-7RI74trqqtbw!2e0!7i13312!8i6656 https://www.google.com/maps/@45.5230331,-122.6802471,3a,75y,...
pixl97 5y ago
Where I used to live in East Texas there was one of these, well, at least a few decades ago. Never knew exactly what it was for. But it is a mirror image of the pictures. The things you learn later in life because of the internet.
flyinghamster 5y ago
Cell carriers often use microwave backhaul as well, particularly when fiber infrastructure is unavailable. These are usually smaller dishes mounted on cell towers, rather than big horn antennas.
__turbobrew__ 5y ago
There is one in Vancouver BC. I always wondered what is is: https://goo.gl/maps/RKVvfiDApVxCWsnj7 https://goo.gl/maps/RKVvfiDApVxCWsnj7
- walrus01 5y ago
  The Telus CO downtown at Robson and Seymour used to have a large tower on the roof with 6GHz horns, linked to that site, and towards the site on Bowen Island which still has horns. Bowen Island was a link to the sunshine coast, across to Nanaimo, and many other places. There is also a big site out in the fraser valley on a hilltop that was part of the long lines network with shots going east towards Hope (trans canada microwave) and down into Whatco County.
  - __turbobrew__ 5y ago
    Interesting! Thank you for the information. Does the trans Canada microwave go along the coquilhalla highway? I notice that there are point to point links along the side of the highway. Were the microwave links to Nanaimo and the Sunshine Coast replaced by fiber?
    - walrus01 5y ago
      There's submarine fiber to Vancouver island now, in a diverse ring, so yes. Still is some microwave operational on sunshine coast but not as a primary thing. Big parts of trans Canada microwave have now been dismantled. There was a mountain top site slightly NE of Hope that could only be reached by its own cable car. And lots of other mountain top sites east of it going all the way to Lethbridge.

ugjka 5y ago

Also known as bird killers

themodelplumber 5y ago

That's a great resource, thank you. I learned just a little about these after making the decision that my drives through Nevada would never again be boring. Once I started asking questions about what I was seeing, the "ice cream cones" or horn antennas really did stand out in a fascinating way. And $25K to buy one does seem like it could be a terrific deal in the right situation. Another thing I asked about: When I stopped to get gas or groceries, I realized there were tall visibility flags on the back of so many Nevadan trucks, even what looked like personal vehicles. I had overlooked them for years. An interesting dive into an industry and its culture started there. BTW, speaking of old towers that went up for sale and are possibly interesting to ham radio operators: Here's one near me (NorCal Bay Area) that was purchased by a local bay leaf grower and then opened for ham radio use--in exchange for a refurbishment effort. https://www.youtube.com/watch?v=GMtkLjHUgYU https://www.youtube.com/watch?v=GMtkLjHUgYU

deleted 5y ago
[deleted]
bombcar 5y ago
What are the flags for?
- dmd 5y ago
  http://www.miningwhips.com/ http://www.miningwhips.com/
  - themodelplumber 5y ago
    Yep, this.
  - nitrogen 5y ago
    They are also for off-road recreational use, e.g. in sand dunes.
ashleyn 5y ago
Growing up in the mountains, I remember seeing a curious kind of antenna up on a mountain nearby. It didn't look like the others; from one angle it looked like a three-petal flower and across town, it looked like a giant robot with two antennae. Wondered what it was for years since it looked so unusual. Only a few years ago I learned it was a long-decommissioned AT&T Long Lines tower: an urban explorer had filmed it. https://youtube.com/watch?v=MvXxNheLATw https://youtube.com/watch?v=MvXxNheLATw

mbostleman 5y ago

Any reason AT&T isn't removing and disposing of these towers?

astronautjones 5y ago
most of them are just on top of mountains or hills http://long-lines.net/places-routes/index.html http://long-lines.net/places-routes/index.html
grendelt 5y ago
Cost. Several of them are hosting cell and radio services so that "pays the rent" on the location. Dismantling and scrapping such a tower would be enormously expensive and bring no value to AT&T shareholders. If they're in total disrepair, I'm sure a case can be made for safety in an urban area. The two towers closest to me are in rural areas with several other radio service tenants where maintenance is a covered cost.
- Aloha 5y ago
  Legacy AT&T owns almost none of them anymore, what's left are owned by the RBOC (often the other AT&T) and as you note, have a prohibitive removal cost and are in urban centers.
aasasd 5y ago
I'm gonna guess that spending money on that seems a highly dubious investment.
- mistrial9 5y ago
  safety and clean-up are always a cost center, on the books.
- dboreham 5y ago
  Almost all the sites are still in use due to the resurgence in terrestrial wireless use in the past 20 years.
5y ago

aasasd 5y ago

> Built in the early 1950s... It conveyed phone conversations and television signals from the era of the Kennedy assassination through the resignation of Nixon Even from the other side of the globe I can tell that it seems strangely short-lived. Built for a decade, then used for a decade? Wikipedia notes tersely: > The launch of communication satellites in the 1970s provided a cheaper alternative.

magila 5y ago
Technology advanced extremely quickly from the 40s to the 70s. Much of what was built in that time became obsolete soon after it was completed.
weird-eye-issue 5y ago
Just wait until you hear about smartphones
- nine_k 5y ago
  Less of a joke than one might think. The GSM / 2G / 3G / 4G / 5G transition took less than 30 years, each step involved scrapping some of the old incapable hardware.
allturtles 5y ago
I think this is wrong. AFAIK satellites have never been a significant channel for domestic phone calls. Microwave relays were obsoleted by fiber optics.
- alrs 5y ago
  > Like their predecessor satellites, the Telstar 3 satellites operate at 6/4 GHz (C band). Simultaneous long distance telephone call capacity is 21,600. The satellites furnish voice, video, and high speed data services. https://www.telcomhistory.org/resources/online-exhibits/science-of-phones/calling-a-country-far-away/ https://www.telcomhistory.org/resources/online-exhibits/scie...

dunham 5y ago

My dad used to work on these towers in the midwest. Back in the day, he told me that they still had plenty of capacity, but AT&T had to switch to fiber after Sprint "dropped the pin".

sgt101 5y ago

BT built a system of underground copper pipes/waveguides for microwave transmission in the 1970's - it never got beyond a testing platform in Suffolk (Martlesham Heath to Wickham Market) due to fibre optics becoming the clear winner.

Aloha 5y ago
AT&T built one as well, the WT4/WT4A system. https://archive.org/details/bstj56-10-1829 https://archive.org/details/bstj56-10-1829
walshemj 5y ago
And some above ground waveguides alongside a main road near Ipswich - not sure if they are still there.
- superkuh 5y ago
  There's some cool but not very ready tech called surface wave transmission lines that use horn like "launchers" to establish surface waves on single conductors like power lines. They have very low RF losses up to the tens of GHz as long as stuff stays a few wavelengths away from the lines. In way, if you try hard enough, most powerlines could act like inside out waveguides for high data rate RF backhaul.
- sgt101 5y ago
  There is a story that the "Radio Tower" at BT Labs was built as a waveguide - this is on the A1214. Given that the office accomodation in it is so weirdly laid out I can believe that this might be so.

kzrdude 5y ago

Interesting. Is there no corresponding podcast episode for this story?

tyingq 5y ago

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://en.wikipedia.org/wiki/AN/TRC-97 https://www.marines.mil/Photos/igphoto/2001740716/ https://www.marines.mil/Photos/igphoto/2001740716/ (apparently still used by the Marine Corps)

ms4720 5y ago
I was one of those techs, 29m
peterangular 5y ago
> 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 https://en.wikipedia.org/wiki/Autovon http://www.coldwar-c4i.net/Echo-Fox/index.html http://www.coldwar-c4i.net/Echo-Fox/index.html
- tyingq 5y ago
  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.

spacecadet 5y ago

My family leases land in Maine for one of these towers. They are still maintained.

cenazoic 5y ago

The Qwest Tower building in Minneapolis referenced in the article has been the CenturyLink Building since 2011, and the microwave was removed in 2019: ref: https://www.startribune.com/after-50-plus-years-the-centurylink-building-in-mpls-sheds-its-crown/561882801 https://www.startribune.com/after-50-plus-years-the-centuryl...

rsync 5y ago
... and is the most beautiful Central Office (CO) building in the United States.

retrac 5y ago

I think this fits the mood. The old telephone system was entirely analogue. It remained so well into the 1980s, even when they were carrying tens of thousands of conversations in parallel on a single wire or antenna. When I was a kid, you could hear the white noise stack successively louder on a long-distance call, as it went through each additional link. And sometimes you could hear the hum of it all, just below the threshold of intelligibility. In hindsight it's amazing how well it all worked. But sometimes it didn't work so well: https://vocaroo.com/1oCxkWyNDusp https://vocaroo.com/1oCxkWyNDusp Maybe a filter was slightly out of tune on that day. Recorded mid-1970s New York. The electronic beeps are in-band call establishment tones. (Yes, the same ones phone phreaks exploited. The recording was in fact made by one of those phreaks who has gone back and narrated some of his old recordings http://www.evan-doorbell.com/ http://www.evan-doorbell.com/ )

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jibcage 5y ago
“Hello? Yes, a collect call for Mrs. Floyd from Mister Floyd Will you accept the charges from United States?” I always wondered what those beeping tones were in the recording at the end of that song (“Young Lust”). I guess I’m not old enough :)
- TedDoesntTalk 5y ago
  Those are in-band signals to the switching equipment. The equipment would “hear” those tones and translate them into “machine instructions”. That’s why phreakers could exploit the system by generating those tones themselves and playing them into the phone microphone.
  - jeffrallen 5y ago
    That's why you do not control networks with signals on the network itself. See also: Facebook's recent outage.

diskzero 5y ago

I lived directly across the street from one of the "Long Lines" towers on Queen Anne Hill in Seattle, WA. [1] It was actively maintained, with various antenna arrays being attached or removed frequently. The building below was packed full of gear and service vans were coming and going all the time. I was sorely tempted to try and climb it over the various years I lived in Seattle, but decided it wasn't worth either the arrest or death by electrocution or ground impact! 1. https://www.google.com/maps/place/315+W+Galer+St,+Seattle,+WA+98119/@47.6323144,-122.3615366,3a,75y,357.71h,110.22t/data=!3m6!1e1!3m4!1sy4UHRwaLuVpqtauIrxZ3iQ!2e0!7i16384!8i8192!4m5!3m4!1s0x5490156b89f8ab9f:0x2b7e34054bd175e7!8m2!3d47.6321641!4d-122.3611876 https://www.google.com/maps/place/315+W+Galer+St,+Seattle,+W...

walrus01 5y ago
the queen anne site is a wireline CO for that region, and has cellular stuff on it. The 6 GHz microwave has been out of service for many years. It used to be a primary link across the sound, to things in Kitsap, and similar. fairly typical USWest/Qwest central office otherwise.

Goety 5y ago

A lot of broken links in that article

ipdashc 5y ago

Love seeing these get brought up. It's a really fascinating system from an era when communications infrastructure was a bit more visible. It's one of those things where, once you learn it exists, you'll start seeing them (the towers/horns) popping up all over the place. My favorite AT&T artifact, though, has gotta be the Project Offices: https://en.wikipedia.org/wiki/Project_Offices https://en.wikipedia.org/wiki/Project_Offices The gist of it seems to be that these are secure, physically guarded, literal underground bunkers built into the tops of mountains along the East Coast, housing troposcatter antennas and satellite dishes. Super cool. As far as I can tell, nobody ever truly figured out exactly what they're for, and most are still operational today. I tried driving up to one once, out of curiosity, and there are some pretty intimidating "stay out of here" signs and cameras, even at the very base of the mountain. Chances are they were simply just meant for the military AUTOVON network, mentioned near the top of this thread. But I suppose that doesn't explain why they're still operational nowadays. https://coldwar-c4i.net/ATT_Project/index.html https://coldwar-c4i.net/ATT_Project/index.html (Funny enough, this website is maintained by the same Albert LaFrance who runs long-lines.net, mentioned in the article) https://coldwar-c4i.net/ATT_Project/VA01/ATTsiteB.html https://coldwar-c4i.net/ATT_Project/VA01/ATTsiteB.html This one is actually decommissioned and has pictures of the inside: https://coldwar-c4i.net/ATT_Project/Buckingham/index.html https://coldwar-c4i.net/ATT_Project/Buckingham/index.html Super interesting stuff, IMO

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js2 5y ago
Wild. I've lived 30 minutes from the one in Chatham for 15 years and never heard of it before. https://www.flickr.com/photos/legeros/albums/72157691603482592 https://www.flickr.com/photos/legeros/albums/721576916034825... http://www.thetownofliberty.com/2018/01/the-mystery-of-big-hole-road-in-chatham.html http://www.thetownofliberty.com/2018/01/the-mystery-of-big-h...
- ipdashc 5y ago
  Yeah they're crazy. Super obscure bits of infrastructure and Cold War history. It's interesting to me how all the signs in that Flickr album say "People" instead of "Personnel" (Delivery People, Authorized People Only). Was this an AT&T thing?

EGreg 5y ago

Does AT&T still send you microcells?

genocidicbunny 5y ago

How serendipitous, I was just watching a show Bob Moses [1] did on one of these towers above LA, and was wondering what they were. Now I've my answer. 1. https://www.youtube.com/watch?v=xKeduffv7_U https://www.youtube.com/watch?v=xKeduffv7_U

NelsonMinar 5y ago

We've got networks like this all over rural America. Only instead of giant towers they're little consumer fixed wireless nodes, getting 1-25Mbps (or more!) via 2.4GHz. 5GHz if you're lucky.

mtippett 5y ago

I had just moved to Toronto in about 2002, and was waiting for an interview. I saw one of those microwave horns on a building in the distance. Puzzling over what it was. Interview started, talking about something glanced over the background and muttered verbally "Microwave" as it hit me that it was a microwave waveguide of some sort. Didn't get the job...

walrus01 5y ago
The entire lower white donut ring around the bottom of the CN tower is a radome, inside are ptp microwave dishes. It was a lot more relevant in the era before singlemode fiber went everywhere. Looks like this inside. https://www.jagelectromagnetics.com/images/jag_cataloug_images/JAG_Catalogues_CN_Tower.jpg https://www.jagelectromagnetics.com/images/jag_cataloug_imag... Nowadays there is some 2.0GHz band ENG stuff up there for live news gathering stand ups.

ksec 5y ago

Why is the Title Edited ? >Vintage Skynet: AT&T’s Abandoned “Long Lines” Microwave Tower Network The original title of the article, actually make sense in the subject of "Long Lines". But the submitted title make it sounds like AT&T totally abandoned Microwave Network. I dont know about AT&T but Microwave Network is still actively being used today and refined even in the latest 5G 3GPP Spec Rel 16, 17 and 18. Other than that it is a nice piece and history of the system.

walrus01 5y ago
PTP microwave is very much in use by many carriers, it's absolutely essential for a lot of modern cellular network builds. But the actual microwave horn antennas in the 6 GHz band, that typified the inter-city AT&T long lines network, are 98% decommed in place these days. You would be very hard pressed to find a site that still has the waveguide, waveguide pressurization system, and a live FCC part 101 licensed 6 GHz radio running on a horn-to-horn path.

gpvos 5y ago

Of course, many countries have had a similar network. I like the towers of the Netherlands, which have similar designs to each other, even though each is unique. A few have a radio mast on top. Click the links at the bottom of https://cellnextelecom.nl/over-cellnex/locaties/ https://cellnextelecom.nl/over-cellnex/locaties/ to get an impression. Currently they are mostly used as data centres, but I think they still provide some microwave links as well.

rsync 5y ago

If you spend any time in the mountains you will see "blank" billboards up in the hills. These are "passive repeaters"[1] for microwave networks and I am surprised they weren't mentioned in the article ... [1] https://en.wikipedia.org/wiki/Passive_repeater https://en.wikipedia.org/wiki/Passive_repeater

walrus01 5y ago
Here's a 1984 vintage PDF for passive microwave repeater engineering: https://az276019.vo.msecnd.net/valmontstaging/vsna-resources/microflect-passive-repeater-catalog.pdf?sfvrsn=6 https://az276019.vo.msecnd.net/valmontstaging/vsna-resources... For the most part these are almost obsolete, the typical data link that many of them carried was one DS3, or at most, three DS3... The path loss is extreme. Usual setup was to go from a small town central office (CO), 3-5 km up to a nearby mountain, then bounce it off there, and 25-30 km to another nearby mountain. With big old power hungry PTP microwave gear that occupied a full 42U rack, took 1200W of power, and carried a whole lot of DS0. Nowadays a modern PTP microwave radio that can carry 1400Mbps full duplex in the 6 or 11 GHz bands is as little as 35W of power, so many hilltop tower sites either have built electrical grid connections, off grid solar, or whatever. Building some of those passive repeater billboards in places with no road access was very costly. Big helicopter bills and very labor intensive. You can still see a number of them on hillsides in eastern Oregon.
- jonah-archive 5y ago
  Spotted one up on Steens Mountain not so long ago: https://www.google.com/maps/@42.4584052,-118.6942825,155m/data=!3m1!1e3 https://www.google.com/maps/@42.4584052,-118.6942825,155m/da...
jcrawfordor 5y ago
Passive repeaters were certainly not common, possibly not used at all in the AT&T Long Lines network. I am not aware of any examples at least. In general AT&T did not like them, it's more common for telephone passive repeaters to have been installed by CLECs or telephone cooperatives, and later on I know MCI used some in this area. These were all later installations than most Long Lines. I'm not sure exactly why AT&T eschewed them besides the speculation that AT&T built much of their microwave network relatively early and so the attenuation may not have been acceptable given the already short range on their links. AT&T's first generation of microwave sites had to put the RF amplifier in a hut on top of the tower because the waveguide loss was unacceptable, for example. A very common place to find passive repeaters in the desert west is at dams, where they were almost invariably installed to provide the telephone connections to the power house. A later interesting example of passive reflectors is the "periscope antenna," mostly used by Western Union when they operated a microwave network for a time. The actual microwave antennas were mounted on the roof of the shack pointed up, and at the top of the tower passive reflectors at a 45 degree angle "bent" it to horizontal. It put the more maintenance intensive parts on the ground at the cost of some power loss.

bogomipz 5y ago

Also worth mentioning that MCI, an AT&T competitor and thorn in their side, also had a microwave relay network. The M in MCI is for microwave. There's some great info on MCI here: https://telephoneworld.org/long-distance-companies/the-history-of-mci/ https://telephoneworld.org/long-distance-companies/the-histo... For those not familiar MCI was a real innovator and an important part of internet history. Vincent Cerf, an internet giant, worked for MCI[1]. Sadly MCI was relegated to the dustbin of history as a result of the WorldCom scandal[2]. They are sadly just a part of Verizon Business today. [1] https://en.wikipedia.org/wiki/Vint_Cerf https://en.wikipedia.org/wiki/Vint_Cerf [2] https://en.wikipedia.org/wiki/WorldCom_scandal https://en.wikipedia.org/wiki/WorldCom_scandal

Goety 5y ago

I kind of want one but i dont think any are still for sale.

razzmataz 5y ago

I used to live in an area served by what was then GTE and they had antennas like this. I have not seen anything listing GTE’s equivalent infrastructure. Does anything exist for that?

dhosek 5y ago

Alas, the linked google maps link for the towers is now 404'd. I was curious to look closer to see if any of the towers near me still existed.

dhosek 5y ago
Ah, but I've turned up this rather comprehensive site: https://long-lines.net/places-routes/ https://long-lines.net/places-routes/

xyzzy21 5y ago

Fun fact: the USSR used exactly the same technology and that is why enabled the US to monitor all phone calls using the Rhyolite/Aquacade surveillance satellite: microwaves are line-of-sight and due to the curvature of the Earth (take that flat-Earthers!), the inter-station signals continue into space and are receivable by a big enough antenna. https://en.wikipedia.org/wiki/Aquacade_(satellite) https://en.wikipedia.org/wiki/Aquacade_(satellite) Fun fact 2: back in the day you could make a "station-to-station" long distance calls - these are the "stations" they were talking about.