don't worry about the swr, you need to build a phasing system that generates
the required feed currents and that can easily contain a network to bring
the output impedance to whatever you want to feed it with.
wrote in message
oups.com...
Hi,
I am using 4nec2 and ICEPAC to design a 4-square inverted L. I think
the far field pattern, SWR, and area coverage are pretty good. I
believe most receivers can hear signals down to -120db fairly well. I
am modelling not only radials but also a ground system to reduce the
SWR and help with the lightning protection. I hacked this out of a
standard 4-square for 80 meters.
Any of the 4-square people out there who can offer additional pointers,
construction details, and other things I have not considered? I'm
finding trouble reducing the SWR from 2:1 down to 1:1
NOTE: Distance T is an arbitrary distance between the ground and a
planned wooden deck roof to help disguise the system. Distance D is an
arbitrarily small distance between the ground system and the dirt.
Thanks much!
The Eternal Squire
CM K6NA - 4-Element W1CF Phased-Vertical Array
CE converted with 4nec2 from AO to 4nec2 format on 22-apr-02
SY T = 9 ft
SY S = 17.3875 ft
SY K = T
SY M = 8.69375 ft
SY D = 0.1 ft
SY W = 8.69375 ft
GW 1 5 -S 0 T -S 0 T+W 1in
GW 2 5 0 -S T 0 -S T+W 1in
GW 3 5 0 S T 0 S T+W 1in
GW 4 5 S 0 T S 0 T+W 1in
GW 11 5 -S 0 T+W -S+W 0 T+W 1in
GW 22 5 0 -S T+W 0 -S+W T+W 1in
GW 33 5 0 S T+W 0 S-W T+W 1in
GW 44 5 S 0 T+W S-W 0 T+W 1in
GW 111 5 -S 0 K -S-M 0 K 0.25in
GW 112 5 -S 0 K -S+M 0 K 0.25in
GW 113 5 -S 0 K -S M K 0.25in
GW 114 5 -S 0 K -S -M K 0.25in
GW 211 5 S 0 K S-M 0 K 0.25in
GW 212 5 S 0 K S+M 0 K 0.25in
GW 213 5 S 0 K S M K 0.25in
GW 214 5 S 0 K S -M K 0.25in
GW 311 5 0 S K 0 S-M K 0.25in
GW 312 5 0 S K 0 S+M K 0.25in
GW 313 5 0 S K M S K 0.25in
GW 314 5 0 S K -M S K 0.25in
GW 411 5 0 -S K 0 -S-M K 0.25in
GW 412 5 0 -S K 0 -S+M K 0.25in
GW 413 5 0 -S K M -S K 0.25in
GW 414 5 0 -S K -M -S K 0.25in
GW 51 5 -S 0 0 -S 0 T 2in
GW 52 5 0 -S 0 0 -S T 2in
GW 53 5 0 S 0 0 S T 2in
GW 54 5 S 0 0 S 0 T 2in
GW 66 5 -S 0 D 0 0 D 0.25in
GW 67 5 0 0 D S 0 D 0.25in
GW 68 5 0 -S D 0 0 D 0.25in
GW 69 5 0 0 D 0 S D 0.25in
GW 70 5 -2S 0 D -S 0 D 0.25in
GW 71 5 S 0 D 2S 0 D 0.25in
GW 72 5 0 -2S D 0 S D 0.25in
GW 73 5 0 S D 0 2S D 0.25in
GW 80 5 -1S 0 D -1S -1S D 0.25in
GW 81 5 -1S 0 D -1S 1S D 0.25in
GW 82 5 1S 0 D 1S -1S D 0.25in
GW 83 5 1S 0 D 1S 1S D 0.25in
GE 1
SY I1 = 1
SY I23 = 1
SY I4 = 1
SY P1 = 0
SY P23 = -90
SY P4 = -180
EX 6 1 1 00 1.0 0.0
EX 6 2 1 00 .0 -1.0
EX 6 3 1 00 .0 -1.0
EX 6 4 1 00 -1.0 -.0
GN 0 0 0 0 13 0.002
'
FR 0 1 0 0 14.01
EN
'From the arrl antenna anthology, vol. 1.
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