Interesting.? ?Thanks for forwarding the link.? ?i ran the default look (which is of reasonable size) and it was a small db down at 20 meters and 20 db down at 80 meters....? ??
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A ton of the people I work with all the time in local clubs are always excited by antennas that are "quiet receivers."? ?Of course, the easiest way to get a very quiet receiving antenna is to use a 50 ohm resistor.? ?(dummy load).? ?Very quiet -- down into
the thermal noise!? ? But not terribly good for transmitting!? ?
All antennas are compromises and one uses what one has to, but I'm interested in emergency work, so efficiency for transmitter work is important to me.? ?Might be very different for someone working with FT8!
Thanks -- I learned something! (As usual on this site)
Gordon
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Here you can calculate it for yourself.? Arv posted this:
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The math is in the other links Arv forwarded¡
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Hmmmm. ?I didn¡¯t see any math to explain the quoted efficiencies of 40 or 90%......??
On May 31, 2019, at 13:51, Jack Purdum via Groups.Io <jjpurdum@...> wrote:
Not true. Our loop is 40% efficient on 40M and 90% on 20M. See:
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Fw: [JackAl] W8TEE Mag Loop Testing
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On Friday, May 31, 2019, 12:30:24 PM EDT, iz oos <and2oosiz2@...> wrote:
As far as I have understood, loops have poor efficiency (something like 10%, ie - 10db), although they might have rx advantages. Did you software modeled it first? What would
the efficiency be?
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Il 31/mag/2019 01:52, "Kees T" <windy10605@...> ha scritto:
Jack,
How do we figure out which reflector to follow for info on the ML Testing since it's on several. Guess this is the largest "member count" reflector, but might not be the best one.
73 Kees K5BCQ
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