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While reading through the comments on that article, I was reminded of my Dad's own journey through the years as a radio engineer. When I was growing up, he was

While reading through the comments on that article, I was reminded of my Dad's own journey through the years as a radio engineer. When I was growing up, he was the market engineering director for one of the two or three local FM conglomerates, and through the past 30 years or so, they kept getting gobbled up by larger corporations until probably 90% of the AM/FM radio audience was owned by either Clear Channel or CBS-then-Entercom-now-Audacy. These groups also cut back substantially not only on local radio talent (there used to be shows through the day run by local DJs, now you're lucky to get a morning show and maybe an afternoon drive show), but also on the radio engineers deployed to the stations. A lot is due to automation and ease of IP audio (and popularity of alternative formats like YouTube and Podcasts), but it's a bit of a sad, slow death of something I remember more fondly as a kid. I recently had my Dad take me on a tour of a 'megawatt' (ERP) FM tower site in St. Louis (we posted a YouTube video of it) and it's incredible the engineering that goes into getting a signal (in the case of this site, 10 signals) into an FM antenna system 300m above the earth!

adamparsons 4y ago
Small world, the youtube algorithm put that video in front of me the other day, enjoy it a lot.
dylan604 4y ago
>it's incredible the engineering that goes into getting a signal (in the case of this site, 10 signals) into an FM antenna system 300m above the earth! this is what always amazed me. we used to drive by/through the local antenna farm in my area, and it always impressed me as a kid that these towers was where the radio/tv signals originated. driving by, you could see the bases of some of them were on a single point of an inverted pyramid which revealed the importance of the guide wires. these were the first structures that i understood to be designed to move. then learning stories of the power of the signal, the amount of electricity to create that power, the fact that the AM signals could change their wattage at night to be more powerful, that video was an AM signal with the audio being FM all multiplexed together. then there was the time that a military jet clipped the guide wires forcing the 2 occupants to eject and causing the station on that tower to go off the air. or the much more gruesome time a local teenager climbed one of the smaller towers, thinking he could recreate an action movie scene, attempted to slide down the guide wires. the attempt was not successful as it sliced off his fingers causing him to free fall catching a lower wire which created 2 halves of him. in case anyone thinks of trying this, don't. after all of that, wound up becoming a video engineer.
- sokoloff 4y ago
  AM stations generally reduce their power at night, rather than increase it.
  - iefbr14 4y ago
    Yeah that was later because the power stations caused too much interference. The reach of medium wave increases at night and you get some local interference of far stations. They mitigated that by raising their local power causing even more interference. FCC stopped that :)
- dreamcompiler 4y ago
  > could see the bases of some of them were on a single point of an inverted pyramid I was under the impression these towers were AM because such a long wavelength is needed for AM radio stations that the whole tower is the antenna, with an insulator between the point of the inverter pyramid and the ground. FM towers are not like this; the wavelength is much shorter and the tower is not part of the antenna. The antenna is a short element at the top insulated from the tower. Happy to be corrected.
  - geerlingguy 4y ago
    FM antennas are indeed placed as high up as possible on these towers, but the tower itself, being a guyed model and not freestanding, does come down to a "ball and socket" joint at the bottom, which allows the tower to move around slightly under the tremendous pressure of the guy wires yanking it down to earth. Apparently there's a deep 25'x25' slab of concrete underneath that holds the socket the tower rests on.
- vel0city 4y ago
  FYI, they're guy-wires not guide wires. https://en.m.wikipedia.org/wiki/Guy-wire https://en.m.wikipedia.org/wiki/Guy-wire
  - dylan604 4y ago
amatecha 4y ago
I saw that video the other day - it was seriously amazing! That you for sharing it! I shared it around with a bunch of people who I figured would find it interesting as well. I would love to tour a facility like that one day, though chances are slim the stars will align in such a way. Who knows, maybe one day! haha :)

adamparsons 4y ago

Small world, the youtube algorithm put that video in front of me the other day, enjoy it a lot.

dylan604 4y ago

>it's incredible the engineering that goes into getting a signal (in the case of this site, 10 signals) into an FM antenna system 300m above the earth! this is what always amazed me. we used to drive by/through the local antenna farm in my area, and it always impressed me as a kid that these towers was where the radio/tv signals originated. driving by, you could see the bases of some of them were on a single point of an inverted pyramid which revealed the importance of the guide wires. these were the first structures that i understood to be designed to move. then learning stories of the power of the signal, the amount of electricity to create that power, the fact that the AM signals could change their wattage at night to be more powerful, that video was an AM signal with the audio being FM all multiplexed together. then there was the time that a military jet clipped the guide wires forcing the 2 occupants to eject and causing the station on that tower to go off the air. or the much more gruesome time a local teenager climbed one of the smaller towers, thinking he could recreate an action movie scene, attempted to slide down the guide wires. the attempt was not successful as it sliced off his fingers causing him to free fall catching a lower wire which created 2 halves of him. in case anyone thinks of trying this, don't. after all of that, wound up becoming a video engineer.

sokoloff 4y ago
AM stations generally reduce their power at night, rather than increase it.
- iefbr14 4y ago
  Yeah that was later because the power stations caused too much interference. The reach of medium wave increases at night and you get some local interference of far stations. They mitigated that by raising their local power causing even more interference. FCC stopped that :)
dreamcompiler 4y ago
> could see the bases of some of them were on a single point of an inverted pyramid I was under the impression these towers were AM because such a long wavelength is needed for AM radio stations that the whole tower is the antenna, with an insulator between the point of the inverter pyramid and the ground. FM towers are not like this; the wavelength is much shorter and the tower is not part of the antenna. The antenna is a short element at the top insulated from the tower. Happy to be corrected.
- geerlingguy 4y ago
  FM antennas are indeed placed as high up as possible on these towers, but the tower itself, being a guyed model and not freestanding, does come down to a "ball and socket" joint at the bottom, which allows the tower to move around slightly under the tremendous pressure of the guy wires yanking it down to earth. Apparently there's a deep 25'x25' slab of concrete underneath that holds the socket the tower rests on.
vel0city 4y ago
FYI, they're guy-wires not guide wires. https://en.m.wikipedia.org/wiki/Guy-wire https://en.m.wikipedia.org/wiki/Guy-wire
- dylan604 4y ago

amatecha 4y ago

I saw that video the other day - it was seriously amazing! That you for sharing it! I shared it around with a bunch of people who I figured would find it interesting as well. I would love to tour a facility like that one day, though chances are slim the stars will align in such a way. Who knows, maybe one day! haha :)