"surfnturf" wrote in news:WN_Yf.1391$_u1.990@pd7tw2no:

While on the topic of antennas, what do you all think about the issue
of RF exposure and the recomendation that omni directional antennas
with a gain of under 9 dB be mounted 5 meters (15 ft) above deck
level?

Even the 1 meter above head level given as minimum height for the base
of the antenna seems to be ignored on many boats.


I'm 60 years old. I got my ham license when I was 11 in 1957 because the
ham I used to pester to death to use his equipment and license figured,
rightly, that was the only way HE was ever going to get on ham radio
again without me in the way.

I've run everything from 1,500 watt HF teletype, CW, digital modes, AM,
SSB on the HF ham bands, creating fields so strong the hall light in one
house use to light up with SSB every time you talked on the mic. I used
to build HF linear amps it took 4 people to carry...(c; I've run over
80KW effective radiated power on VHF/UHF for things like bouncing signals
off the moon, long haul troposcatter where lots of power is required,
etc. Your skin got hot if you stood in front of it. I've operated an HF
mobile SSB station at 650 watts output on all the bands, in fields so
strong the dash lights in the car glowed from the wiring picking up the
intense field.

I've been around broadcast transmitters up to 100KW on FM and 25
megawatts on UHF-TV (ERP). They radiate an amazing array of RF, Xrays
from the intense voltages applied to the klystron tubes that are longer
than you are tall. I've climbed AM radio towers to replace the light
bulbs. AM radio antenna IS the tower, itself. I've been on that tower
with the transmitters running full power....5KW, 10KW. You learn quick
not to touch the OTHER side of any insulator you come to to keep from
burning your hands. I've been in the transmitters with the cabinet open
trying to figure out what's arcing at 5KV, 10KV, 25KV from a power supply
that looks like a substation. You can hear the RF "hissing" in there...
(c;

I'm 60. I had one trip to the hospital to retrieve a kidney stone back
in the 80's. I drink distilled water, now, because it HURT! I've always
been, basically, kind of ugly, but that was genetics, not RF's fault...

I'm still sailing and in good health....(c;

RF is dangerous. Too much RF from a cellphone, for instance, causes the
cellphone to occupy the channel over too wide an area, reducing company
revenues per square mile. So, we generate a public panic that cellphones
are too powerful and are causing terrible cancers over your ears. The
public sucks that up like a sponge....and loses its mind allowing the
cellphone companies to turn their power levels WAY down so the phone
range just sucks something awful. New phones run .15 watts, tops.
Cellphone companies are thrilled...revenues are way up!

If RF is deadly, then we MUST turn off all commercial transmitters,
immediately! That 100KW FM rap station down the street is killing you!

If we're running out of oil, we need to ground all airplanes, stop buses
and trains and stay home to conserve, right?

Neither will ever be implemented, of course. It's about the money...