n4pcloop.nec

zip contains tool for Antenna Modelling with examples

CM N4PC Loop (CQ, Dec. 1990), converted with 4nec2 on 29-mrt-06 14:37
CM 	N4PCLoop
CM This multiband horizontal loop antenna was created by Paul
CM Carr, N4PC, and described in December, 1990 CQ Magazine. A
CM unique feature is that it's driven at opposite corners by
CM out-of-phase signals as in the W8JK antenna. This results
CM in an overhead null on all bands. If you look at the input
CM file description, you'll see two (split)sources shown IN phase.
CM This is necessary due to the direction current is assumed
CM to flow in the wires. When multiple sources are placed in
CM connected wires as done here, you have to check the
CM resulting currents to make sure they're flowing in the
CM directions you thought. If not, you must reverse one or
CM more sources. Note also the relatively large number of
CM segments for each wire. On 20 meters, the 51-foot sides are
CM approaching a full wavelength long, so it's necessary to
CM use an appropriately large number of segments.
CM This is also an illustration of the use of split sources to
CM allow source placement at wire junctions.
CE
GW 1 16 0  0  50 0  51 50 3.367e-3
GW 2 16 0  51 50 51 51 50 3.367e-3
GW 3 16 51 51 50 51 0  50 3.367e-3
GW 4 16 51 0  50 0  0  50 3.367e-3
GS 0 0 ft		' All in feet.
GE 0
EX 6 1 1 0 1 0		' Split I-src 1
EX 6 4 16 0 1 0
EX 6 3 1 0 1 0		' Split I-src 2
EX 6 2 16 0 1 0
GN 2 0 0 0 13 5.e-3
FR 0 1 0 0 14.1 0
EN