Michigan is a Prime Target of Terrorist Attacks?
Old people like to tell stories and my granpda was no exception. He didn’t usually make up stories, but sometimes it was obvious that he had gotten his information from a single source a single time and you didn’t always know how right or wrong he was.
One such story Grandpa used to tell me about how Michigan was a prime terrorist targets because the US had radio towers there to control the nuclear sub fleet. I always thought that was weird, because wouldn’t the army have more than one radio station? And why would you put radio stations for subs so far from the rest of the Navy?
Turns out he was right about the radio tower part (still not convinced on the terrorist target part).
How and Why of Submarine Radio in Michigan (and Wisconsin)
FM radio operates in the Mega Hertz range, eg 106.9 FM means that the station operates a frequency modulated radio broadcast on the 106.9 MHz, or 106,900,000 Hertz, wavelength. That means the radio waves are relatively short and you can use a relatively short antenna to send and receive that radio signal. AM uses longer radio waves and needs longer antennas which is why Walkmans and cell phones can include FM radio easily, but not AM.
To broadcast radio through the water to the depth that submarines operate you need to use extremely low frequencies in the 76 Hz range.
Republic, MI and Clam Lake, WI had Extremely Low Frequency radio stations that did indeed broadcast to the US submarine fleets. The radio stations couldn’t be built just anywhere because the antennas need to be “2,140 to 3,726 miles” (thanks Wikipedia!) long. Since a wire antenna that big would be unwieldy, the army hooked 26 mile wire antennas into the bedrock and let the earth be a big antenna. The locations in Wisconsin and Michigan had the right kind of rock to make that easier to do.
The radio stations have been decommissioned since 2004 which makes me wonder how they’re communicating with subs today.
Reading and Learning Comes Full Circle
My grandpa had lots of interesting stories because he was always learning. He subscribed to and read Scientific American and the Reader’s Digest and the Stars and Stripes magazines, among other publications. He was a news man that loved news. I can’t count the times he would literally pull me to his side, and point emphatically at some section of an article which he had circled and underlined with a ball point pen.
I like to think that he learned about these ELF radio stations from an article in one of his magazines. You see, I also love reading news and science articles. Most of my reading today is done online, including today’s big find. Lockheed Martin and the Department of Defense are working on making two-way communications with submarines possible.
Let me state for the record that I fully intend to tell my grandkids about this some day.
More information about the Clam Lake location can be found at the Federation of American Scientists website.