Your post brings out more questions such as how did you test the antenna
prior to installation> What are the resonant frequencies now and do you get
a 13-30MHz antenna to even work on 30 meters. Personally I would not use
the mast as a tower just to obtain more distance from the guy wire. If you
have solid steel guys below it you should consider changing them to a
non-conductive material or breaking them with insulators.
The main purpose of my post is to make sure that your tower guy properly
installed the coax. It should not be taped to the hot boom. Doing so will
cause the coax to radiate.
GL,
John KK9A
Dave Thompson K4JRB wrote:
Gang,
I have a Tennedyne T-10 older model with a 24 foot boom. I tested this beam
before the tower guy put it up on my 70 foot Rohn 45.
I found that the SWR was 1.3 to 1,4 on all bands except 30 meters where it
is 1.9. Now mounted on the tower at just over 71,5 feet the SWR on all
bands except 20 an 10 is the same. The SWR on 20 is 1.8 but tunes to flat
with my Ten Tec 3229 tuner The SWR on 10 is 2.2 to 1. But does tune with the
tuner but not as easily as the 20 meter portion. I have been told by K9LA
and others that most Tennedyne antennas will work on 6 but have mot tried
it.
The tower guy said the beam bumped the house on the way up which means the
front elements may be loose. I got a S shaped screw driver to tighten the
screws holding the elements in place. The beam is mounted about 9 feet below
the 2 el 40 Cushcraft that has given me good performance for years and i
rebuilt with the aid of parts from MFJ/Cushcraft.
I was warned that the antenna did not like metal guys so it is 18 feet to
the nearest guy but the 8 foot spacing was less than the
11 feet I had planned. The tower guy said with the 20 foot 2" .25 aluminum
mst I used that the extra spacing might cause the mast to bend. The 4o meter
beam has an overhead strut that uses up almost 4 feet of the mast so 11 feet
was the most I could separate the beams. I got the antenna from W6XA who
knew the original owner of Tennedyne in Texas and he told me that the screws
being loose might cause the problem. He was surprised that the 20 meter SWR
went up as the usual interaction with a 40 meter beam affected 15 not 20.
The element lengths were set by W6XA for max performance and not touched.
All I had to do was attach the elements.
I need any other ideas on 20 and 10 operation from users of Tennedyne
antennas, I did work Asia easily on both 20 and 40 during the recent All
Asia SSB. 10 has been dead so I have not tried it but plan on trying the
band soon.
My problem is that I used a Crank up tower so I could tilt it over or crank
it down prior to the Rohn 45 so I did all my own antenna work. Now I have to
use an outside tower person so can't do the work myself.
Thanks for any help.
73 Dave K4JRB
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