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What happens when you touch a pickle to an AM radio tower

jeffgeerling.com

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Re: What happens when you touch a pickle to an AM radio tower

#131

Post by BenjiWiebe »

justanother wrote: post #40

I understand he got permission and everything was checked out by actual RF eggheads, but damn. I won't even change a HV run capacitor unless i'm wearing crocs, standing on cement, and wearing the rubber oven mitts. And even then, I keep one hand behind my back. Because there have been accidents, and they hurt (the pool pump run cap fails approximately annually in this climate and if I paid someone to change it every…

Does your pool pump run capacitor actually not have a bleed resistor? I thought that was standard issue in start/run capacitors.

Re: What happens when you touch a pickle to an AM radio tower

#132

Post by Johnythree »

ck2 wrote: post #73
JCM9 wrote: post #62

For folks wondering why these sort of videos (there are lots on YouTube) always focus on AM towers: 1. On AM the radio energy literally pulses (the amplitude modulation) and thus the arcs of plasma will pulse too thus creating the audio noise. AM has a carrier wave that’s constant but the two sidebands of signal pulse from zero energy at silence to more power the louder the sound being transmitted. FM signals broadca…

The history of AM radio and the invention of the mechanical sparkgap transmitters by Reginald Fessenden is absolutely fascinating. Imagine only having telegraphs and morse code and amateurs listening every night to the spark noises in morse then suddenly in 1906 (first done in 1900 !) you hear voices and music! https://en.m.wikipedia.org/wiki/Reginald_Fessenden can't seem to direct link the photos but scroll down to…

You have it backwards:

Fessenden is famous for developing a electomechanical RF generator which put out a clean sinewave (eg a coherent wave), which helped replace the earlier Spark-Gap systems (which generated wide-band hash).

Re: What happens when you touch a pickle to an AM radio tower

#133

Post by Johnythree »

JohnMakin wrote: post #39

I always wonder if there would be any pain in the death that results from touching one of these. I’d assume it’d be instant from the electricity traveling through your heart - or would you just burn up more slowly?

Because your nerves don't respond to high frequencies, you cannot "feel" RF current.

What you do feel is the intense burning associated with the RF energy being converted to heat.

Re: What happens when you touch a pickle to an AM radio tower

#134

Post by Johnythree »

JosephRedfern wrote: post #64

I'm curious as to how much paperwork was involved here. Was the pickle grounding out the transmitter and (presumably) interrupting the broadcast not an issue?

The pickle will shunt (steal) some signal, but the radiated power from the antenna will be very much greater than that flowing through the pickle.

Re: What happens when you touch a pickle to an AM radio tower

#135

Post by greesil »

stavros wrote: post #18
greesil wrote: post #4

Not to state the obvious, but isn't there a damned good reason the tower is fenced off? You can see the fence in several of the pictures.

You can also see the reason in several of the pictures.

That's my point. This is ridiculously dangerous.

Re: What happens when you touch a pickle to an AM radio tower

#136

Post by dessimus »

edm0nd wrote: post #97
dekhn wrote: post #78

Earlier quoted context omitted.

One of the authors, Alan Eustace, was an exec at Google (in the days when execs at Google had a clue) and also holds the record for highest jump (135K feet).

Bill Gates can actually jump over a chair. og Tech execs are awesome at jumping it seems!

Necessary life skill with Ballmer on the Executive team.

Re: What happens when you touch a pickle to an AM radio tower

#137

Post by bArray »

dgacmu wrote: post #81
bArray wrote: post #67

Earlier quoted context omitted.

I went through it (admittedly many years ago), but ham licensing wouldn't really do anything for safe radio operation. I learned the real stuff from two very experienced operators. It would probably be easiest to regulate the transmitters than the people using them.

Me too, but at least there's some stuff in there (for extra) about RF safety. Not a lot, but enough that someone with an extra class license should know that they need to go do some calculations about the safe distance from their antenna based upon radiated power, etc., and hopefully that's enough to get them to actually do it. IIRC there was a question or two in the pool about RF burns. Not much in there that would…

Electrocution I think is an easier risk to manage than the RF side, it's less intuitive and you'll be burned but not necessarily understand why. Ham is better than nothing, but I wouldn't feel personally comfortable operating a 1kW+ AM rig.

It seems like it needs more thought, but I still like the idea of de-centralised community AM transmitters operating.

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