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4015 MARINE AUTOMATIC ANTENNA TUNER
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 (earth) system is the
primary cause of poor performance and tuning problems. There is little point in
installing the antenna unless a good ground (earth) system or counterpoise can
be provided.
Whichever method is used, the ground (earth) run from the ground (earth) plate
to the antenna tuner should be as short as possible and use copper strap at least
50 mm wide (wider if available).
Metal Hulled Vessels
Metal hulled vessels provide an almost perfect ground (earth). The tuner ground
(earth) terminal should be connected directly to the hull using the shortest possi-
ble ground (earth) 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
Wooden or fibreglass vessels present more of a problem to ground (counter
-
poise). Ideally the vessel should be fitted with an external copper ground (earth)
sheet, connected to the interior of the vessel by suitable stud or an ground
(earth) plate (“E” plate Barrett P/N BCA91700)
Should neither of these methods be available, acceptable ground points include
stainless steel stanchion, through mast, through hull or a metal water tank.
NOTES:
•
Do NOT connect the ground terminal to anything combustible i.e a gas or
electrical pipe, fuel tank, engine or oil catch pan
• Ground cables should not be connected to more than one ground point.
• Consideration must always be given to the problem of electrolysis. Severe
structural damage may occur if electrolysis is present. Consult your maritime
experts for more information concerning electrolysis.
