Hy-Gain TH-3JRS, Инструкция по эксплуатации

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The first feedline configuration involves connec-
tion of the coaxial feedline directly to the driven
element. The recommended feedline is RG-213/U
(such as Belden 8267). Other types of coaxial
cable may be used if proper selection and careful
assembly are utilized. The feedline should be
stripped as shown in Figure 7. Attach solder lugs
(not supplied) to the center conductor and shield
for easy connection to the driven element.
Weatherproof all connections.
The second feedpoint configuration involves con-
struction and installation of a homemade RF
choke. The RF choke will prevent RF from flow-
ing on the outside of the coaxial shield. This will
block radiation from the coaxial feedline; thereby
reducing the risk of TV1 and preventing radiation
pattern degradation.
NOTE: Use caution when selecting a balun to use
with this antenna. Some baluns are designed for
50-75 ohm impedance and may result in a higher
SWR when used with this antenna. For best
results, use the Hy-Gain BN-86, 50 ohm balun.
The Model BN-86 is available at your local Hy-
Gain dealer.
Carefully recheck all measurements, make certain
the drain holes in the traps are facing down and
then tighten all compression clamps securely.
Make certain all electrical connections are tight.
Weatherproof your coaxial connection using
Coax-Seal (R) or some similar substance.
Slip the boom-to-mast clamp over your mast and
tighten securely.
Wind the RF choke from RG-213/U ( or
equivalent) coaxial cable. The choke should con-
sist of 12 turns with an inside coil diameter of six
inches. Allow enough cable at the end to reach
from the mast to the driven element. Strip the
coaxial cable as shown in Figure 7. Attach solder
lugs (not supplied) to the center conductor and
shield for easy connections to the driven element.
Weatherproof all connections.
This completes your installation.
WARNING
Installation of this product near power lined is
dangerous. For your safety, follow the
installation directions.
The third feedpoint configuration involves using
a 50 ohm 1:1 balun to connect the feedline to the
driven element. (Hy-Gain Model BN-86 is
recommended.) A balun will act as an RF choke
and will balance the flow of current on the driven
element, resulting in a symmetrical radiation pat-
tern. A balun will also have a coaxial connector,
providing more convenience than a coax splice.
Follow the instructions supplied with the balun
for connection to the antenna.