Today on Geerling Engineering, my Dad and I toured the tower site for WSDZ-AM, located in Belleville, IL. It's a 20kW AM radio station broadcasting with an array of eight individual towers:
How does one get a single coherent signal out of an eight-tower array? Enter the phasor:
That's phasor with an o, not phaser with an e, so Trekkies need not fret about a misspelling.
...except it was a beef frank. Make your wurst jokes in the comments.
What you see above is the remains of a hot dog after it has been applied to an AM radio tower operating in its daytime pattern, at around 6 kW.
A couple months ago, soon after we posted our If I touch this tower, I die video, a few commenters mentioned you likely wouldn't die after touching a high-power AM tower—rather, you'd have serious RF burns.
I was trying to figure out a way to somewhat safely test the scenario: what would happen if someone walked up and touched the tower, while standing on the ground?
If reading's not your thing, check out the short video we posted on Geerling Engineering:
Nearing it's centennial, KMOX-AM (1120 kHz) is a 50,000-watt clear-channel AM radio station with studios located in downtown St. Louis, MO, USA.
But their broadcast tower is located about 10 miles northeast, in Pontoon Beach, IL. My Dad was the director of engineering overseeing the tower and studios for about 20 years, and though he's no longer there, he and I got permission from Audacy and the St. Louis engineers (thanks!) to tour the site, and learn a bit about how they broadcast their AM signal—which reaches all the way into Canada and Mexico at night!
In this blog post, I'll write a bit about KMOX's tower system (AM towers are a lot different than FM, like the FM Supertower we toured last year), the transmitter, and the some of the history found at that tower site.
...that was the question I asked my Dad, a radio engineer for many decades, who worked at the biggest AM station in St. Louis, KMOX. The station is approaching its centennial in 2025, as are—some YouTube commenters argue—its primary audience!
I recorded that video during my convalescence at my parents' house (I am feeling much better now, thank you!), and my Dad discussed a few reasons why AM radio—at least in the US—is not dead. But it is suffering.
In the video, I pointed out the current dichotomy:
As the son of a radio engineer, I've seen my share of radio towers. From small, rural AM and FM towers to urban 'constellation' towers serving dozens or even hundreds of services, there's a lot more than meets the eye.
My Dad and I visited the so-called 'FM Supertower' in St. Louis, MO twice now, to explore the tower and the supporting infrastructure below. Both of these visits are documented on our Geerling Engineering YouTube channel:
My Dad and I just posted a new video on the Geerling Engineering YouTube channel where we explored the tallest radio tower in the St. Louis metro area, the so-called 'Supertower' that has a 10-station combined dual FM antenna system (dual 4-bay FMVee by Dielectric) at the top:
Over on the Geerling Engineering YouTube channel, my Dad and I just posted a video where we installed the ASUSTOR Lockerstor 4RS - AS6504RS at his radio station, to increase their raw network storage capacity from 4 to 16 TB:
In the video, we focused on the installation, though I highlighted the unit's top-line features at the beginning.
In this blog post, I'll quickly recap the main features, then give more impressions of the unit from our experience setting it up, and my Dad's use of it at the station since we recorded the video.
In a strange coincidence, the authors of TinyPilot and Pi-KVM both emailed me within a week of each other and asked if I'd be interested in one of their KVM devices.
Michael Lynch, founder of Tiny Pilot, said he'd used some of my Ansible work in building the TinyPilot update system, and Maxim Devaev, of Pi-KVM, liked my Pi open source content, and wanted to see what I thought of the new v3 kit that's currently on Kickstarter.
I took them both up on the offer, and dug into both devices.
Both have HDMI and USB inputs, so you can plug them into any Mac or PC and get full control, up to and including BIOS/UEFI settings, remote desktop management (with no software on the managed computer), and mounting of USB ISO images for re-installing an OS or maintaining a system.
Last year I spent a lot of time in the hospital. Between multiple surgeries and outpatient visits and follow-ups (either intentional or through an unexpected ER visit), I probably spent at least a month or two in a hospital room. For a time, you could see the exact date ranges I was checked in by the holes in my GitHub contribution graph! Such is the life of an open source developer.
Despite appearances, this was not a very fun recovery!
I didn't have much time today to post this earlier (I was driving home from a trip which took me through five states in six days, and had to do this on the road), but this afternoon I was on the excellent 'Catholics Next Door' radio show on the Sirius XM Catholic Channel.
I was happy to speak with Greg and Jennifer Willits about flockNote, about parish communications, and about helping Catholic organizations get connected to their flock in various ways.
Then I continued driving home from Chicago :)
I don't know if they have an online archive of their shows, but if I can find a link to the audio at some point, I'll try to provide it. I'm also not too familiar with satellite radio, since I've never subscribed (Pandora + free radio has worked for my musical tastes), so I don't know if there are any rebroadcasts or ways of listening to past shows...