It's like the warnings on bread toasters and TVs that tell you not to
use
the item while showering.
wrote in message
roups.com...

Shortwave Sportfishing wrote:

On 19 Jan 2006 18:18:36 -0800, "
wrote:


I have just received a ICOM fix-mounted VHF radio. To my
surprise, its
instruction says that I must keep the bottom of the radio antenna at
least 1-meter (3.3 feet) away from our heads if the antenna is
mounted
in a small boat. I have never heard this before. Is this for real?


yes.


Does this have something to do with strong radio frequency may
boil our
brain or cause cancer?


not cancer - the brain boil thing. turns it to mush at 25 watts. its
why i wander around with this blank look on my face.


Does this restriction also apply to 3dB antenna?


all antennas - including car radio antennas, portable radio antennas -
anything that has an antenna.


Does this mean that I need to use an extension to keep the
radio antenna further away from our heads?


at least three feet - further away is better. its best to put the
antenna on a mast at least three feet tall - ten feet tall is the
best.


Thanks in advance for any info about this "unexpected" restriction.


there is no direct evidence that radio waves cause cancer or boil your
brain. there is anecdotal evidence, but it has to be very high power
- like in the megawatts - at the marine radio frequency.

put your antenna where its easy for you to raise and lower and dont
worry about that stupid - rule - its legal beagles being legal and
stuff.


Thanks for clarifying this issue to me. Sound like this is not a
"real" issue for a VHF radio that only uses up to 25 watt.

Jay Chan


I spent 17 years as a military electronics tech working on
communications and nav equipment, with much experience in VHF. During
that time, I was required to submit to various regular periodic medical
tests and exams including extensive eye exams due to my exposure to RF
radiation. And I only worked with low-power radios and terminated all
power output into loads when transmitting on the bench - I never had an
antenna next to my head. There is an enormous body of research as well
as plenty of anecdotal evidence of specific damage to body and brain
tissue from various frequencies. Anyone who tells you that RF radiation
- any RF radiation in close proximity, isn't harmful is uninformed. That
doesn't mean you are going to get cancer or fry your brain from your
vhf, but a little caution certainly doesn't hurt. BTW, the most rapid
deterioration in my eyesight was during the period I worked more with
comm radio transmitters.