A 5 Band Log Periodic
Dipole Array
In ARRL Antenna Compendium No. 4, I desribed how I modified the Telerana
which was orginially featured in the July 1979 issue of QST. The unique
feature of the Telerana is that the elements are wire instead of aluminum
tubing which makes for a light weight LPDA (log periodic dipole array). The
array is suspended within a framework made of fiberglass poles emanating from
a central hub with the ends tied together with light weight rope around the
perimeter.
Here is a
picture taken of my Modified Telerana taken from below.
Modifications to the orginal Telerana design includes adding parasitic
reflectors for 15 and 20 meters to improve the front to back ratio on these
bands. I also described how I added a trap 30/40 meter inverted Vee that acts
as a top truss system to keep the Telerana from turning upside down like an
umbrella might in high winds. Below the modified Telerana is a homemade 4
element 6 meter Yagi. This system allows coverge of all amateur radio bands
from 40 to 6 meters without an antenna tuner, on one tower, with only 3 coax
feed lines. This very compact system worked very well. I used this antenna
system from 1986 until 2005. My rotatable antennas are supported by a 60 foot
Wilson telescoping tubular tower. With the Modified Telerana I worked 293
contries with confirmed QSLs from 275 countries! As well, I have worked 121
countries at QRP levels!
In 2005 my tubular tower collapsed within itself and destroyed the Telerana
and 6 meter Yagi. After re-cabling and painting the tower I replaced the LPDA
with a Steppir Yagi and two stacked 5 element 6 meter yagis below.
Vol 4 of the ARRL Antenna Compendium series is no longer in print however I
have scanned a copy of the article, "The Improved Telerana, with Bonus
30/40 Meter Coverage": here (Copyright
ARRL. All rights reserved, used with permission of the ARRL.)
You may also find an abbreviated version of the Modified Telerana article in
recent ARRL Antenna Handbooks.
I
received this picture of (Dec. 2004) UA0SB and his copy his version of the
Modified Telerana.
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