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GregS
 
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Default VHF Antenna Recomendation

In article , Bruce in Alaska wrote:
In article WN_Yf.1391$_u1.990@pd7tw2no, "surfnturf"
wrote:

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.

surfnturf



RF Radiation is NOT ever going to be a problem on ANY non-commercial
vessel. Period. None of the radiators that one can buy and install
ever even come close to maximum RF Radiations Power Densities considered
the Safe Levels. The same is true for most commercial Marine
installations. My only concern would be to make sure that any MF/HF
Antenna system be well insulated at any place where a person could come
in contact with it. GTO-15 certainly would do this job for wire
antennas, or a nonconductive insulating layer applied to any other
antenna section that is within reach of a humans. The worst that could
happen, should a person come in contact with the above, while
transmitting, is that they could get an RF Burn, that is going to smart


When I was in the Army, I would test my transmitter/antenna system
out by touching the antenna to get a burn and I think I learned that from others, don't
remember. If it burned, then it was OK. The antenna was a 1/4 wave vertical and transmitted
to the Northrop drone planes. I later made a separate box to have a lamp indicator
when placed near the antenna. The hing was, there was no indiction on the transmitter
if a cable connection was bad.

When I was on a Carnival cruise in 1986, I ventured up to the radio room. Took me back,
I saw a man using a bug or some kind of key, sending CW. The antenna
wire came out of the rack, up the wall, along side of which was a light bulb flashing in tune with
the CW. I thought it was pretty neat.

greg