Codan Envoy Reference Manual page 439

Positioning the tuner
Due to high voltages on the antenna, position the tuner so that the antenna-to-tuner
connection is isolated from accidental contact with conducting surfaces.
WARNING: It is essential that the antenna be positioned at least 50 mm (2 in) from
CAUTION:
Connecting the antenna to the tuner
When routing the antenna wire to the tuner:
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Earthing the tuner
The earth system is a key part of the overall antenna system. An inefficient earth
system is a primary cause of poor performance and difficulty in adjusting the tuner.
The earth system should be connected to the earth stud on the tuner by a heavy copper
wire or braid. The connection from the tuner to the earth must be a small percentage
of the total length of the antenna, that is, the earth braid must be kept as short as
possible.
CAUTION:
In areas of good earth conductivity, an effective earth can be established with an earth
spike. The spike should be approximately 3 m (10 ft) in length and should be installed
as close as possible to the tuner. It may be necessary to use several earth spikes bonded
together to improve the earth contact.
Copper or steel water pipes can be suitable earths, provided that:
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E ™ T R
NVOY RANSCEIVER EFERENCE
a conducting surface.
Avoid kinks in the lead-in wire of the antenna.
keep the length of the antenna wire inside the building to a minimum and away
from metal objects
a minimum hole diameter of 100 mm (4 in) is necessary for wiring that passes
through a wall or roof, and the wiring should pass through the centre of this hole
using a grommet or other suitable insulator
wiring must not come into contact with guttering, eaves etc, upon entering or
leaving a building
Do not use an earth strap that exceeds 1.5 m (5 ft).
the water pipe is close to the tuner
the water pipe enters the ground very close to the tuner earthing point
there are no joints or couplings in the pipe that may increase the resistance path
to earth
the water pipe makes good contact to soil that has good conductivity
a low resistance connection is made to the water pipe
M
ANUAL
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NSTALLATION
F
IXED STATIONS
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