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BARRETT 4050 HF SDR TRANSCEIVER - OPERATING AND INSTALLATION MANUAL
Antenna
On sailing vessels the antenna can either be an insulated backstay or a whip
antenna mounted vertically, usually on the stern. Best performance will be
achieved by using an insulated backstay as the radiating length will be longer
than that available when using a whip. The top insulator on the backstay
should be approximately 300 mm from the mast and the bottom insulator
should be at eye level above the deck. The distance between insulators should
be greater than 10 metres and less than 35 metres. A whip antenna is generally
used on small to medium sized power vessels. There are different length whips
to suit the vessel length.
Transceiver and Tuner Mounting
Select a suitable position in the vessel to mount the Transceiver. It should be a
position that is out of the weather and easily accessible to the operator, whilst
as close as practical to the 13.8 V DC power source. Mount the Transceiver to a
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at the rear of the Transceiver to connect the power and antenna cables.
The antenna tuner should be mounted as close to the antenna feed point as
possible. In metal vessels the length of the feeder from the antenna tuner to
the feed-through insulator, inside the vessel, should be kept less than 1 metre.
The antenna feed cable should be a suitable high voltage cable. Care should
be taken to avoid sharp points when terminating the cable to prevent corona
discharges.
The interconnect cable supplied with the antenna tuner should be routed away
from other cables back to the Transceiver and connected as indicated in the
diagram overleaf.
Ground (Earth) System
The ground (earth) system is a key part of the overall antenna system and con-
sequently the system operation. An inadequate ground system is the primary
cause of poor performance and tuning problems. There is little point in install-
ing the antenna unless a good ground system can be provided.
Metal hulled vessels provide an almost perfect ground. The tuner ground
terminal should be connected directly to the hull using the shortest possible
ground strap. The point of connection to the hull should be prepared so that it
is free of paint and rust to ensure a good contact area with minimum electrical
resistance.
Содержание 4050 HF SDR
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