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I am looking at an AM antenna nearby. I have done quite a few off one with a output listed as being 5kW. The one im looking at is 50kW. Being ten times a higher output, im thinking that it's safe to say it's a no go. I've done some trawling and can't seem to find any info, in plain English, as to what you can get away with. Does anyone here have much experience (real world, first hand experience) with live AM antennas?? Being a higher output, would it mean the risk of earthing out while trying to get onto the A would be greater due to more current going through it??

it's not worth it. that's my only input.

unless of course you can turn it off (or down).

Is it possible to use a wooden ladder to access the object? Once you're on it will be OK for a few minutes probably. You might not be impregnating any females for a few days though...

I'm not sure what the power level of the towers I have been on (working while they are hot) but I can tell you for sure after about 15 minutes you start to feel weird. Mildly queasy, a little lightheaded...and supposedly it is not the greatest for your internal organs, though others have assured me that there is no longterm damage (who knows right since the typical tower climber is not exactly the paradigm of health).

IMO, there will be greater shock risk if you ground out, in addition to more cooking of your organs while you're on the tower. If you do it, do it quickly.

Ask NickDG...

or, ask the new skydiver at my old DZ, ~5+ years ago... a 40-jump wonder who bought a rig and tracking pants on the internet... thought it would be easy to huck the nearest antenna with no training or knowledge. Fortunately when he grounded the antenna he was blasted backwards far enough to thoroughly reconsider his approach before he killed himself :)

He was a nice guy, it opened his eyes, and he was very humble about the experience. I think he said it knocked his shoes off and burned holes clear through his leather gloves. Obviously, you personally are not going to ground it. One huck might not kill ya but I would worry about cancer especially if you made it a habit.

I still fly over that antenna on a regular basis. You can get great reception on the NDB from several states away. My fantasy is that they decommission it some day. And that naked retareded ninja trannies are waiting at the bottom.

I know of two jumpers who've been shocked by AM antennas and they turned out fine. One of them even had two kids. But enough about me..... ahem, ahem......I say GO FOR IT. You need to understand how AM antennas work and make sure you are not a path to ground. My mistake was misidentifying the antenna due to painted ceramic bases and trusting the other jumper (who had multiple leaps from it in the past) that it wasn't hot. Felt like a bee sting.

Worst case, bring someone dumber than you and make them climb first. Bring a wooden rake handle that can be used to beat his/her appendages off the tower during an electrocution.

I'm not too concerned about the shock factor, avoiding that is pretty simple. Im mainly after someone who may know what levels are tolerable, and what are a definite no go! The one I usually jump is pumping out 5kW, but there is an epic looking one that is pumping out 50kW. I have heard its a no go, but I havent heard it from anyone who has first hand info. I am also looking at a couple that are putting out 10kW. One way to find out hey?!

Here is an interesting tidbit I found on an Australian government guide to RF radiation:

Broadcast towers produce weak RF EME exposure levels in the everyday environment. The weight of national and international scientific opinion is that there is no substantiated evidence that RF EME emissions associated with living near a broadcast tower poses a health risk.
To date, the only health effect that has been proven to exist as a result of exposure to RF EME relates to heating of part or all of the body. This is known as the thermal effect, and the ARPANSA Radiation Protection Standard “Maximum Exposure Levels to Radiofrequency Fields – 3 kHz to 300 GHz”, which sets public and occupational limits of exposure to radiofrequency radiation, is designed to avoid adverse heating effects where people are exposed to RF EME.


Hmmmm... PARTY TIME! Hahaha

I will clarify my last post. In theory this kind of radiation should not directly mess up your DNA and cause cancer that way. That is straightforward science. Studies that once claimed to find an association between cancer and high voltage lines, or cell phone antennas, or other transmitters have also all been discredited.

I wonder though, and maybe any other medical-types could chime in. There are plenty of case reports of workers getting burns from accidentally working on active transmitters. Usually UHF or microwave, not AM band. You can heat up tissue and cause thermal injury from being near EM radiation in general, it depends on the power, the frequency, and your body. And if you were to repeatedly cook your insides, that is probably not good for them in the long term. There is not exactly a lot of long-term research the field of in vivo organ cooking, if you know what I mean. So what effect this has on your vital organs over the long term, who knows. It's definitely conceivable that repeated cycles of injury and repair could increase your odds of pathological scarring, or some kind of cancer. 5kw vs 50kw I couldn't comment, except that 50kw wont be better for you.

Climbing it a certain number of times will never kill you, in all likelihood (the jump itself is another matter of course). But what happens if you find out you are getting cooked, and you are starting to get sick with vomiting, and you are halfway up? Do you climb down real fast, or climb up real fast? That is a bad spot to be in and I have no desire to explore that. But plenty of people have climbed these things and have been fine. It's just me being a pussy.

Also another thing to think of. The general safety reassurances that are given apply to people who live a considerable distance (i.e. more than centimeters) away from the transmitter. Power density from a transmitter decreases proportionally to the square of the distance, which is great if you are far from the transmitter. But if you are close enough to climb on it, you can get an enormous dose of energy.

Those government reassurances that you read were designed for the inhabitants of nearby houses, not for people climbing it while transmitting.

I still think you should climb it though, and tell us what happens :)

I jumped one a few years ago and it fucked me up. I had to jump to get on the ladder, after I had climbed over a 16 foot high cinder block wall and had trapped myself in. (Had 50 jumps at the time, was going hard and had no idea how to spot an AM except it had a ceramic base, which I saw after I jumped inside the wall). Anyway, I only made it 400' or so up the full 640' before I was running out of daylight and (now knowing I was climbing AM) paranoid I was gonna wreck myself.
Jump went ok, landed and felt like shit for 3 days. I never puked (some folks have told me this happened to them), but I was dragging ass for awhile. Just felt like I was exhausted and suffering from general malaise, had some anorexia to go with it. (think of AMS symptoms).
Fast forward 18 months and I tried to jump a freestander in Alaska. I had never heard of a freestanding AM tower, so I thought it was good. Had concrete bases, covered in snow, seemed grounded. I put my gloved hand on the concrete and it knocked me on my ass so fast it wasn't even funny. burned a hole through my glove and into my palm that took weeks to heal. Come to find out they use a lot of freestanding AM towers up there for long range comms.

Long story short, I don't fuck around with AM anything anymore, I look for ground wires religiously, don't go near an A with insulators on the guy wires or base and haven't jumped an antenna in nearly 2 years.

-Harry

You think AM sucks, try climbing right next to a Doppler.

Aren't AM usually freestanders? Because of the isolator thay need to be placed on?

nah... both are quite common. they use small guyed antennas set in arrays, they put isolators in the guy wires as well.

Many AM antennas are turned down or completely off at night. This of course is due to a bunch of physics hocus pocus involving the ionosphere thingy.

this is true. AM waves are more efficient in the night atmosphere. you can look up what a specific tower's broadcast wattage is based on day/night.

i've worked on many of them. it could be my own paranoia, or being loaded with a half knowledge of how things in the world work, but there are things about AM wave propagation that are simply unknown. it is simply a personal feeling at this point, but i was taught and trained over the decades to be wary of AM and other things that produce RF burn.

no one that i know of has ever died from climbing an antenna due to RF exposure... but that doesn't mean it's a good idea. it is what it is. BASE jumpers are kind of dumb and stubborn though anyway i've found.

In Aussie land most of our jumps are at night and I have jumped some A's that where pushing out that much power we could hear what they where transmitting that night it was the grey hounds racing and yes we had to jump up on to this one. Lots of good times on A's.

damn, so that badass freestander with the ball in the middle is off limits?
im not going to find out myself, whats the deal with them?

Probably safe. The average output of Doppler radars and marine radars are less than 30kW but I still feel like shit after climbing next to one. Probably psychological but you can feel the rotation of the disks spectrum.

you won't get sick if you stay off the doppler...

What are you using to do this?

I was going to reply to your thread.........but now i'm too busy staring at your avatar.....boobies....i like boobies....big boobies..... I <3 ( . Y . )

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