Hello Topbanders,
I have a 65 ft tower with a TH7 and 40-2CD on top and 16 radials from
1/8 to 1/4 wavelength long. I have shunt fed it for 160m with a
jumper across the 18 inch spaced shunt at abt 50 ft. It seems to
work pretty good. The SWR is almost flat across the entire 160m band.
Is that typical?
I also tried to add an 80 meter shunt on the opposite side of the
tower. I havn't been able to find an optimum jumper point on the
shunt. The lowest SWR has been 2:1 and the bandwith is quite narrow
(which is OK). The performance has been poor. I probably just need
more time to refine it. My question regards interaction between the
two shunts. It appears that the 160m performance has decreased since
I added the 80 m shunt. Could this be true or is it just my biased
judgement or band conditions?
Have any of you had success with a combo 160/80 m shunt fed tower?
Any guess where the 80 m jumper would be with 18 inch spacing?
Thanks for reading my questions and for your response if you can
help.
73,
Jim Hood, K5TT
President, Oklahoma DX Association
wv5s@icon.net
Past operations: KC6SS, V63SH, /XE, /WH6, /NH7, /KP2
Previous calls: WV5S, W0PUD, W7KDH, K5TWD
USA-CA # 432
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