I took the KX3 manual into the smallest room in the house for a few
minutes this morning, and was quite dismayed by what I read under the
heading of "Grounding and ESD Protection."
The manual says "A ground system using buried rods and/or a ground
counterpoise (wires radiating out from the antenna) can reduce receive
interference and help prevent electrical shock or damage due to
electrostatic discharge (ESD)."
A connection to earth DOES provide ESD protection and lightning
protection, but it is NOT part of a solution to noise elimination, and
does NOT make an antenna work better. Those wires extending out from the
antenna are correctly described as radials or a counterpoise, but they
are NOT a "ground," and they DO make the antenna work better by
providing a return for antenna current, and for the EM field produced by
the antenna. Indeed, the earth is really a big resistor, and any current
that flows in it results in wasted transmitter power. Indeed, an
important function of a good radial system is to SHIELD the antenna's EM
field from the lossy earth! And those radials do NOT reduce receive noise.
A couple of paragraphs later talks about "Pedestrian Mobile Ground" and
says "if you plan to transmit, you'll need a trailing ground wire to
serve as a minimal counterpoise and greatly improve your transmitted
signal." Again, that wire IS a counterpoise, it IS part of the antenna,
and it DOES improve your transmitted signal, but it is NOT a "ground" wire.
Earlier on the page, under the heading of "Antennas," is the statement
"If you use a short whip, vertical, or a single wire, a ground of some
kind is necessary (described at right) to provide good transmit
efficiency. Dipoles, inverted Vs, beams, quads, and similar antennas
have an inherent counterpoise, making ground optional, though still
desireable."
Again, the word "ground" is the wrong one to describe radials or a
counterpoise. And a connection to earth is desirable ONLY for lightning
and ESD protection -- it does NOT make the antenna work better, nor does
it reduce noise or RFI.
These paragraphs demand a serious and immediate rewrite. Yes, we've seen
serious errors in equipment manuals for as long as I've been a ham, but
we expect more from Elecraft. It is yet another example of confusion and
muddled thinking resulting from using the word "ground" when other
words, like "radial" and "counterpoise" convey the correct meaning.
73, Jim K9YC
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