Hi-VHF + UHF HUM4 (9.5x9-in) with 2 Sizes of Reflector Rods (RR) analyzed using 4nec2.
Nikiml's new CMD--OPT Python Script Optimization commands are now embedded in 4nec2 Files, where the fol. is the contents of the *.bat Python Control File (your's may vary):
cd c:\Python27 python -m nec.opt --num-cores=7 HUM4_9-5_9_BS0_4+7RR-2Sizes_PY.nec pause
Two examples are shown, a sparse lower performance model and a medium performance model where I chose the number of RR's for roughly equal F/B Ratio in each Band out of the twelve I've run thus far. Note there are about TWICE as many UHF RR's as for Hi-VHF. (More runs are planned, esp. with more RR's.)
Hi-VHF SWR is just a bit over desired 2.7 target, which I could fix by adjusting Target Function to increase the "importance" (multiplier) for the "max_ml" term. But instead I ran a Parameter Sweep for RS (Hi-VHF Rod-to-Bowtie Separation), allowing a user to PICK whether they want MORE GAIN (smaller RS) or BETTER SWR (larger RS).
=========================================================== a) HUM4+4RR+7RR with 4-RR for Hi-VHF and 7-RR for UHF: Bowtie-to-Hi-VHF-RR Separation RS=13.0 Bowtie-to-UHF-RR Separation-in RS2=5.5-in
UHF Raw Gain = 10.3 to 13.7 dBi, F/B & F/R Ratio Min = 11.9 dB and SWR (300-ohms) Under 2.4. Hi-VHF Raw Gain = 6.4 to 7.0 to 6.7 dBi, F/B & F/R Ratio Min = 13.3 dB and SWR (300-ohms) Under 3.4.
=========================================================== b) HUM4+8RR+15RR with 8-RR for Hi-VHF and 15-RR for UHF: Bowtie-to-Hi-VHF-RR Separation RS=13.0 [Or 14.5-in to push Hi-VHF SWR under 2.8 with 0.5 dB Gain reduction.] Bowtie-to-UHF-RR Separation-in RS2=5.5-in
UHF Raw Gain = 11.9 to 14.9 to 14.5 dBi, F/B & F/R Ratio Min = 15.3 dB and SWR (300-ohms) Under 2.5. Hi-VHF Raw Gain = 6.6 to 7.5 to 7.2 dBi, F/B & F/R Ratio Min = 15.1 dB and SWR (300-ohms) Under 3.2.
Date(s): 9 Jan 2014. Album by holl_ands. 1 - 42 of 42 Total. 8999 Visits.