Maybe I've Been Triggered

Maybe I've been triggered because I'm sensitive to the topic, maybe I'm sick of the same old ... stuff, but I saw something supposedly coming from Bobby Kennedy and the MAHA folks.  I've spent hours looking for it between yesterday and today but couldn't find it again.  Which makes me doubt talking about this, but it's a slow news day.  

What I'd swear I saw was a list of things that they're supposedly interested in looking into the health effects of the High-frequency Active Auroral Research Program (HAARP).  Coming from a career in radio design - transmitters, receivers and all the major subsystems in them - I've heard absurd fear of radio signals for so long, I start subconsciously twitching when I come across a new story.  

Let's start here.  Most people don't think this way but every minute of every day you live immersed in a constant soup of radio signals.  Forget about your phone or your home WiFi router, the things you usually think of, there are sources from almost audio frequencies through broadcast radio, shortwave broadcasters, TV over the air, police radios, taxi radios, weather radios and on and on up into the microwave spectrum and beyond that into what are called millimeter waves that you're exposed to every day.  Some of them all day, some of them irregularly or intermittently.  Unless you take absurd steps to prevent this - forget the tin foil hat, it's more like a tin foil 100% cover - you live in this every day.  If you turn off your phone, you turn off what it produces; the signals from every other phone and every cell tower are still there.  

So let's think of it in another way the most people won't.  The first law of Toxicology - the study of toxins or poisons is "The Dose Makes the Poison" and the guy who started the field said a big enough dose makes something toxic that isn't usually thought of that way.  The classic example is oxygen; not just nontoxic but essential to life, as in without it we die.  At a high enough partial pressure, it's toxic.  That's why really deep sea diving doesn't use compressed air but exotic mixes of other gases and oxygen.  

A big enough "dose" of radio will burn you.  Since radio is just very, very far infrared light, it immediately brings to mind a laser.  Lasers are high power lights and dose is the power.  Can high power radio hurt you?  Absolutely!  That's why there are limits imposed on the power that systems can produce that people can be exposed to.  The power required to hurt someone depends somewhat on the physical size of the radio waves; the allowable power for a system to expose the general public to is lowest around the FM broadcast band because people are similar in size to 1/4 wavelength at some point in the FM band, depending on how they're sitting; 234/freq. in MHz gives 1/4 wave, so 2.66 ft @ 88 MHz and 2.17 ft @ 108 MHz.  

The saving grace of all that radio soup we live in is that it's all low power by the time it gets to us.  Radio signals drop off in power very fast.  It drops to 1/4 of the power every time you double the distance from the transmitter.  A relationship I've shown many times here is a bit less accurate than the fully rigorous calculations, but it's easy to stick in a spreadsheet somewhere and use it when you need it.  

Path loss in dB = 37 dB + 20log(f) + 20log(d)  where f is the frequency in MHz and d is the distance in miles.  

What's a dB?  It's a decibel, a power ratio.  A loss of 3 dB is 1/2 the power, -6 dB is 1/4, -9 dB is 1/8.  So imagine you're calculating how much power you're exposed to from an FM broadcaster in town. 

Path loss in dB = 37 dB + 20log(100) + 20log(10)  where f 100 MHz and d is 10 miles

Path loss is 97 dB

Now 97 dB is a lot of loss, but FM broadcasters often start out with high powers.  I have a local FM station here in town that says they start out at 1000 watts.  Us Receiver guys refer to that as 60 dB more than 1.00 milliwatt or +60 dBm transmit power (dB is ratio, dBm is a power ratio to 1 milliwatt).  Taking away 97 dB of that gives me -37 dBm.  That's a perfectly usable signal to a radio receiver, but it's 3.2 millivolts RMS or .0032V on digital voltmeter. That's not going to hurt anybody or anything.  

So let's do the same thing with HAARP, according to their documents.  The frequency is 2.7 to 10 MHz, and the distance depends on where you are with respect to the transmitter.  Essentially the distance is up to the ionosphere and out to your location.  The ionosphere covers a fairly wide range of altitudes, but at most is in the "couple of hundred miles" range (photo below) and the altitude will drop out of the equations for a path to the center of the country.  Some web searches show the center of the US is just outside of Lebanon, Kansas, and that it's close enough to say 3300 miles from HAARP.

Path loss in dB = 37 dB + 20log(10) + 20log(3300)  where f 100 MHz and d is 10 miles

Path loss is 127 dB

The power of HAARP is variable, the antenna pattern can change plus there are other differences depending on what the experiment is. That said, 3.6 Million Watts is 95.6 dBm and after the path loss the level is close to previous example - a bit stronger at -31.4 dBm or closer to 6mV, .006V.  

Atmospheric layer heights from Wikipedia

I tried to pick numbers for the distance that weren't too far from or too close to Alaska to be reasonable, but it's a bit surprising that these numbers ended up being within a couple of dB for a local, low power FM station and HAARP.  Bottom line is I still see nothing about that situation that's remotely scary.  As a general rule, the only time a radio signal can be dangerous is if you're close enough to touch the transmitter.