Basejumper.com - archive

who here has hands on experience jumping am antenas?

i understand that the whole structure is transmitting, and that it is insulated from the ground for a reason, dont complete that circut..

what about the radiation? how serious is it really?
how much exposure is acceptable?
if you were climbing fast to minimze time on tower, would you be more susceptible due to exertion?

i ask, because there is a once in a lifetime,sentimental jump for me, however im pretty sure its am...

Check this thread http://www.dropzone.com/...truckerbase;#1318209

I think Truckerbase is the jumper you should ask.

Get on - Get up - Get off . . . is the advice used for years concerning AM towers.

As far as health risks there are dueling studies concerning exposure to Electro Magnetic Radiation (EMR). The ones funded by power companies say the risk is minimal, while the studies done by some Universities say it's the kiss of death. Keep in mind these studies usually only deal with people living in close proximity to very high voltage power lines and not someone actually touching them.

Some people are more prone to developing cancer and other problems than others. So there is no one answer to this one. It’s a risk, that’s for sure, but it’s sort of the same risk we take every time we play the game.

Keep in mind however that the operators of these AM towers think there is a risk. No worker ever climbs a really hot AM tower without it being de-powered or completely turned off . . . In fact there was a tour arranged by a local radio club to the old 700-foot KFI AM tower in So Cal and the operators powered the tower down before they would let the tour even stand next to the base of structure.

NickD
BASE 194

thanks to both.. tb coverd it all.

ask tower toper his name is vince and he has been building antennas for years but i jump them all the time and nothing iks wrong with me except i always shit and piss in my sleep \for a week strait after jumping an am A
just sleep in the bath tub its an easy clean up

I'll start by noting that I agree with your recommendation to "Get on, get up, get off". Although my understanding is that the effects of RF radiation at the usual antenna doses are temporary, they still suck, and cooking yourself for longer than you have to is probably a bad idea.

Still, the above strikes me as a grossly inaccurate characterization of our understanding of the risks of RF radiation. I have read only two technical papers on the subject, but between them, the one by Motorola (done for OSHA) restricts itself to a few specific recommendations for tower workers and makes no comment on the effects of exposure, while the one by the FCC states that the literature is inconclusive on the existence of non-thermal effects (while the thermal effects it lists certainly couldn't be called the "kiss of death" unless you're having lunch in front of a directional microwave antenna).

I'd be grateful if you could share a citation for one or two "kiss of death" University studies.

Sorry, I'm not organized enough to have citations right in front of me. The problem with these studies are they don't reflect what "we" are actually doing. It also depends on the power of the tower. The KFI tower I mentioned saw thousands of jumps before a plane was accidentally flown into it. This tower was especially hot and it was called, “The 50,000 watt flamethrower,” by folks in the radio business. I do know that at night, and under the right conditions the signal from KFI in Los Angeles could be picked up in New York.

Any study done by Motorola is suspect because that have a dog in the race.

The other ones I’ve read talk about the heating of body tissues, and especially the eyeballs which are stated to be very sensitive to internal heating. On the practical side I’ve seen plenty of people over the years complain of feeling “woozy” after a tower jump while others aren’t affected at all. I’ve seen Tom Sanders spend a entire day on a tower (in this case it was a pre-arranged legal FM tower) filming and he was absolutely green and feeling sick for the rest of the night. Also try taking a video camera onto an AM tower and see what you get. It won’t be much.

In the very early days we’d think nothing of spending a half hour on top of KFI, just relaxing and taking in the view. We just didn’t know any better back then. It was also about then we noticed while doing final gear checks that the hardware on our gear was warm to the touch. In fact one jumper lost a riser after opening when the small riser ring melted the white loop holding it in place. This was when fouling your three ring so it couldn’t release became popular.

I used to advise new BASE jumpers to just stay away from AM, but I may have softened my stance a bit as long as they know the score. And the score is we simply don’t know what the long term effects of EMR are . . .

NickD
BASE 194