On Sat, 13 May 2006 23:05:11 -0500, Jim P wrote:
>Maybe I'm missing something in regards to the caveat: "and
operate
>on the lower HF bands".
The receiving antenna (within the subject wired with the
electronic device) needs to be a significant fraction of a
wavelength to receive significant voltage from the transmitting
antenna. So, all things being equal (distance, power, etc.) lower
frequencies will induce less current in the human body than higher
ones by virtue of the electrical length of the receiving antenna
(the human body).
Example -- LF and VLF broadcast stations transmit with
considerable power (100 kW to 2 MW), but RFI from these stations
to audio equipment is almost unheard of. Why? The receiving
antennas are FAR too short as a fraction of a wavelength at these
frequencies to be efficient receiving antennas.
Remember, I'm assuming an HF transmitting antenna that may be
wires or a vertical of some sort, and thus potentially close to
the subject, which is what the original post described. I know
this setup well -- I lived with it at the QTH that I just moved
away from (see the link on qrz.com to my website).
73,
Jim K9YC
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