BARRETT 2030 HF SSB TRANSCEIVER
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Ground (earth) system
The ground (earth) system is a key part of the overall antenna system and
consequently the system operation. An inadequate ground system is the primary
cause of poor performance and tuning problems. There is little point in installing
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.
Wooden or fibreglass vessels present more of a problem to ground. Ideally the
vessel should be fitted with an external copper ground sheet, connected to the
interior of the vessel by suitable stud or an earth plate ("E" plate Barrett P/N
BCA91700)
If the vessel is yet to be constructed, then in the case of fibreglass vessels a thin
copper sheet with an area of not less than 4 square metres should be moulded into
the hull during lamination. A suitable heavy strap should be connected to the sheet
and left free for earth connection.
Should neither of these methods be available it will be necessary to bond as many
large metallic objects, such as the engine and propeller shaft, together to form a
ground.
Whichever method is used the ground run from the ground system to the antenna
tuner should be as short as possible and use copper strap at least 50mm wide
(wider if available). Consideration must always be given to the problem of
electrolysis. Severe structural damage may occur if electrolysis is present.
Corrosion
All connections in marine situations are subject to corrosion and oxidation. To
minimise this all joints should be cleaned and have silicon grease applied before
assembly. Under severe conditions joints should be protected with self vulcanising
rubber tape.