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Old March 5th 07, 12:57 AM posted to rec.radio.amateur.policy
[email protected] LenAnderson@ieee.org is offline
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On Mar 4, 3:09�pm, John Smith I wrote:
wrote:

*...

Well, anyway, if not for these six fingers, I don't think exposure to rf
is all that dangerous. *grin

Actually, I did hear tell of guys up in alaska working on radar, decades
ago and before microwave ovens, they found holding their hands over the
slits in waveguides "warmed" their fingers--then some started ending up
with pains in their hands--cooked partially fingers are painful!

I have never heard of HF causing any medial problems which can be proved
to relate. *However, UHF and beyond is quite different ...


Ahem...take a look at the chart in Part 97. Maximum
allowed power before having to do an "evaluation" is
500 W at 40m but it drops down linearly to 50 W at
10m. All bands at VHF at 50 W. At UHF it is 70 W
at 70cm and rises to a maximum of 250 W at 13 cm
and holds there on up to maximum frequency of
anyone's allocations.

When I was at Fort Monmouth Signal School in '52
and taking the radar systems introductory class,
cadre used to put a wad of steel wool on the end of
a bamboo pole and hold it in front of a 1 MW peak
search radar. Steel wool blazed! One of the wesen-
heimers made a remark about "it was dangerous to
steel wool" with much ha-ha-ing from the group. The
next day we got a demo with a slab of outdated
(uncut) bacon. Instant fried bacon. Wisenheimer
shut up. Search radar was somewhere in S Band
or 2 to 4 GHz. (microwave ovens are 2.4 GHz)

When I worked at Hughes Aircraft Co., El Segundo,
CA division, one of the airborne radar final check-out
guys got one hand slightly fried from playing around
with adjustments with the (F-94?) radar. Wore a
large bandage for about two months after returning
from a medical leave of about a month. That was '57
to '59 time period. Peak powers ain't something to
fool with, not up-close and personal to the RF source.

On the other hand, the tower monkeys who service
the TV and FM towers on Mt. Wilson overlooking
L.A. aren't shielded and seem to survive. Was an
article about them in L.A. Times about a half year
ago. TV and FM sit right in the most sensitive
frequency region for RF Exposure. Go figure...

73, LA