Considering an inverted L and thinking about the tie points you have on a city
lot I did some real rough plots in EZNEC just to see the effect of raising or
lowering the end. Figured you tie the end to a 6' fence or 16' eave in the
worst case. This chart shows the R portion of the Z on a +/- 140' long wire
adjusted for the lowest SWR at 1.8 mhz and is very interesting. These were
perfect ground calcs.
Keeping the top horizontal or sloping up appears to be very important. For a
crummy antenna like this, the radiation pattern probably isn't nearly as
important as the radiation resistance.
Interesting that a 30' vertical with 110' horizontal and 30' high at the end
just might work as well as a 55' vertical with sloped section tied to a 6'
fence.
Maybe someone would like to add the DB loss/gain expected.
Vertical Feet Height at end R
30' 6' 2.17
30' 16' 3.46
30' 30' 5.73
30' 40' 7.71
35' 6' 2.88
35' 16' 4.21
35' 35' 7.47
35' 40' 8.51
40' 40' 9.33
50' 50' 13.31
55' 6' 5.57
55' 16' 7.35
55' 25' 8.97
55' 55' 15.38
Rick, N6PE
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