"Ian Jackson" wrote in message
...
In message , XPye
writes

"Dave" wrote us
For these loops, they are quoting a front-to-back ratio of 6dB. I was
unaware that loops HAD a
front-to-back ratio.
--
Ian

which side is the front? i wonder if art had anything with designing
these?


The front is at the halfside where the gammamatch is attached. So you
point the
thing with its sides closest to the gammamatcher. 6 dB is a power
increase of 4 times
gentlemen ! The are available in three sizes. It stays on your
mind, doesn't it ?


6db f/b can also mean a signal DECREASE to 1/4 of the 'front' signal
strength in the 'back' direction. it doesn't mean that there is gain in one
direction, simply that more power is going one direction than the other. i
can build a small loop and add a small vertical very close to it and
generate probably 20-30db f/b ratio, but it's signal compared to a dipole or
even a 1/4 wave vertical will suck... those antennas have been documented
for many years, but no one bothers using them for transmitting, only for
transmitter hunting as receive antennas.