I have now installed a loop each vert leg 50 ft approx x each horiz 105
ft =5250 sq ft
Next stage is to resonate the loop. I have to decide where the feed
point is going to be ie a bottom corner or a top corner or bottom middle
or top middle, series or parallel feed. Series feed seems to be popular
in the USA and a toroid matching transformer. I use 50 or 70 ohm coax so
have to match accordingly for my rx/tx.
So far connected up unresonated, it is poor as expected compared with my
resonant vertical.
A grounded quad loop is also a consideration, as an alternative to a
closed loop with the bottom horiz leg about 6ft above ground.
There is also some interaction with my vertical ground system, the loop
is affected by the vertical ground radials but the vertical is not
affected by the loop.
This first observation puts some doubt on some previous tests on Decca
sites with a small vertical in the vicinity of a large ground radial
system, where the small vertical was supposed to radiate better than the
main antenna.
The loop is located about 50 ft away from the vertical and its
associated ground radial system and because of the close proximity I
might not be able to do a meaninful comparison test. I do not intend to
dismantle the vertical because it works so well. I can work and hear all
the activity on 136 khz, so apart from some fun I do not need another
antenna. I will resonate it on 136 khz and even with the interaction see
how received signals compare.
73 de MalG3KEV
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