On 1/5/20 7:11 PM, Jim Brown wrote:
What I HAVE done (about ten years ago) was to add a second #10 THHN to
my Tee vertical for 160M, spaced roughly 8-10 inches from the first,
wired in parallel top and bottom. The vertical section is 100 ft. The
measured result was to approximately double the SWR bandwidth.
So, going from l/d of 12000 to 120 -> that's a big, big difference, and
the change in SWR bandwidth would be expected.
My experience has been that when I correctly define the model (wire,
insulation, height, soil parameters) NEC gives me pretty good
correlation with what I measure when the antenna is built and installed.
An example: for a CQP site we used for several years, I modeled a 40M
dipole at the height we were able to rig it in the scrub trees at the
site, and over poor soil, which is what is there. The model predicted 75
ohms, so we brought RG11 for it. Our SWR bridge that was referenced to
75 ohms read close to 1:1 at resonance.
73, Jim K9YC
On 1/5/2020 9:57 AM, Jim Thomson wrote:
10 gauge wire provided for a much wider BW, vs the 16 +18
gauge I tried previously.
2 other folks here in town tried the same experiment...with
same results.
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|