- 13 -
Connections
The feed line should be run away from the antenna at the exact center to the antenna element. If
possible, bury the feed line for some distance from the antenna. This helps to decouple the feedline
from unwanted noise. A
DXE-RFCC-1
Receive Feedline Choke will also ensure feedline
decoupling.
Connect a suitable 75 Ω feedline to the type F connector
OUTPUT
. Leave a small loop in the
feedline to relieve stress on the
AVA-2
connection and securely attach the feedline to the mast
below the mounting plate.
The feedline connectors must remain dry. Do not place any intentional DC shorts or opens on the
feedline between the
NCC-1
and the
ARAV3s
. This includes lightning arrestors, splitters, or any
other accessory not intended for feedlines that carry power or control voltages.
Coaxial Cable Feedline
Flooded 75 Ω CATV type feedline cable (F-6) is strongly recommended for use with the
ARAV3
systems.
DXE-F6
Flooded 75 Ω CATV type feedline cable has a bonded foil to improve shielding.
Moisture typically seeps in around the shield and can cause increased noise. Flooded style cables
have the distinct advantage of automatically sealing small accidental cuts or lacerations of the
jacket. Flooded cable also prevents shield contamination and has a gummy liquid inside that seals
cuts or nicks, displaces water, and can be direct buried.
The feedline is used to provide power for the
AVA-2
matching unit. We
recommend the use
of
DXE-SNS6-25
Snap-N-Seal type F connectors to
ensure high quality and weather resistant feedline connections. Use the
proper tool to crimp these connectors.
To help decouple the feedline from radiated noise, bury the feedline for some distance from the
antenna when the feedline reaches the ground. A
DXE-RFCC-1
DX Engineering Receive Feedline
Choke will also ensure feedline decoupling, which may be installed in-line, preferably at the station
end.
Low Frequency Response - Internal Jumpers
The sensitivity response of the
ARAV3
system does not need to be changed for most installations
above 3.5 MHz. However, if you are interested primarily in frequencies below 3.5 MHz, jumpers
may be required to optimize or increase sensitivity or eliminate interference from strong broadcast
stations.
Set the jumpers to the lowest operating frequency desired.
Refer to
Figure 9
for
various jumper settings.
For access to the jumpers, loosen the two #2 Phillips Screws on each
side of the
AVA-2
unit and remove the chassis from the bottom.
