From NEC2 to the real world with accuracy
Scott, WU2X wrote:
"I`ve always known that I would use #12 solid copper wire (not stranded)
so that is what I used when running NEC2 to optimize this touchy antenna
design (over millions of iterations).
Bill Orr, W6SAI devotes Chapter 9 in "All About Cubical Quad Antennas"
to tuning and adjustment.
John Devoldere, ON4UN wrote on page 13-52 of the 2nd edition of
"Low-Band DXing:
"I designed the quad (for 80-m) with two quad loops of identical length
(for a 2 mm OD conductor or no.12 wire).
William I.(Bill)Orr, W6SAI wrote on page 77 of the 2nd edition of "All
About Cubical Quad Antennas";
'the individual gamma devices are made of #12 solid copper wire and a
small variable capacitor."
Ed Laport pictures a Wind Turbine Company insulator used for two wire
balanced lines on page 485 of "Radio Antenna engineering". These were
used in WW-2 Signal Corps fhombic antenna kits to support the 600-ohm
feedline. The wire was a cable made from (3) #12 twisted Copperweld
wires. This same cable also was used to make the rhombic curtain which
contained (3) of these Copperweld cables. I used many miles of this
cable and never saw a breakage in normal use despite years of aging in
all weather and the fact that we were using 100 KW in an antenna kit
designed for 5 KW. We did redesign the stainless steel dissipation lines
to withstand the high power. With new dissipation lines installed we got
many letters of complaint from South America from listeners who had
benefited from our bidirectional antennas which were intended to cover
central Europe only. Too bad, but other broadcasters claimed the target
area we were temporarily occupying in South America.
Best regards, Richard Harrison, KB5WZI
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