I found this Engineering Report Order number 391S covering technical data
and comparative Test data to the TH6DXX Antenna
The report shows which elements are active on each band, plus electrical
and mechanical comparisions. There is a slight advantage to both average
and peak gain for the TH7DX. There is a slight advantage to the TH7DX for
front to back except on 10. The biggest advantage is the bandwidth
especially on 10.
I also remember Steve K7LXC pointing out that the TH7DX is slightly better
than the TH-11 in gain on the 10, 15, and 20 meter bands. The TH7DX does
not cover 12 and 17.
Good report if you can get your hands on it. This was published by Telex
Hy-gain with no date shown. The order number was 5314. Probably copyright
so someone needs to ask MFJ/Hy-gain if this is still a current publication.
73 Dave K4JRB
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