In a message dated 99-08-03 00:18:16 EDT, firstname.lastname@example.org writes:
> Just got the TH11 up and find out that the VSWR on 17 meters is relatively
> high, about 1.9. BTW, rechecked all measurement 4 times while on the
> so there is no chance for a wrong element length. All traps where
> disassembled and checked for integrity. The Autek analyzer calculates a 1.0
> VSWR at 17.760 Mhz though. Approximately 10 feet above the TH11 is an old
> Gain 402BA which is as high as the mast will allow. The TT archives say
> acceptable spacing is anywhere from 8 to 14 feet. IMHO, I think the trouble
> is the 40 interaction causing the VSWR to rise.
I haven't had any experience with this combo but a TH11/402CD was fine
at about 8 foot spacing and beautiful at 10+ feet. A TH11/XM240 combo with
about 8+ feet spacing degraded the TH11; turning the 40M 90 degrees made it
worse. Maybe the TH11 is problematic with a stacked 40M yagi.
> Any thoughts and possible cures, short of a new mast?
Roger Cox from Hy-Gain has unsubscribed but may have some answers.
Let me know if you want his email address. I don't know how much better it'd
be with more spacing.
Cheers, Steve K7LXC
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