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COAX CABLE RUNS
Some coax cables available have a steel core with a copper coating. Whilst these cables are
stronger when pulled through ducts etc., their electrical characteristics are inferior to cables
of all copper construction. When used with the BH259, for example, steel cored RG59 cable
will correct to only about 500m as opposed to about 1,600m achieved by copper cored
RG59. When purchasing or assessing an existing cable, it is not always obvious which is
steel core or which is all copper. A magnet can be helpful!
As with any medium/long distance coax cable installation, care should be exercised when
making a join or terminating the cable run. Join with proprietary 75Ω coax connectors and
ensure ongoing protection from moisture ingress. Resistive connections, spaghetti wiring,
bulky terminal blocks, damp leakage, etc. will cause picture noise and degrade performance,
due to crosstalk, impedance mismatch, line reflections, etc.
GROUND / EARTH LOOPS
Significant earth potentials may exist across the long distances the BH259 can be run,
ie.1,600m If using earth returns at both ends of the line these may introduce an earth loop.
If present, these disturbances will require the addition of, where appropriate, an opto-isolator,
a video isolating transformer or a camera/source with ‘floating’ output (ungrounding one end
of the line). The intensity of an earth loop may vary over time.
SPIKES & EARTHING
The BH259 contains devices to protect its internal circuitry against spike disruptions from
power glitches, nearby lightning strikes etc. However, the standard device is ground
independent and relies on the local destination equipment (monitor etc.) for line termination
earthing. If preferred, a version of the unit can be supplied fitted with an earth stud for
localised earthing. Details may be obtained from our sales department.
END OF LIFE DISPOSAL
When this product eventually reaches the end of its working life it needs to be disposed of
correctly to prevent damage to the environment. It should not be disposed of with general
household type waste.
If you phone WeeeCare plc on 0844 800 2004 and quote our Account Number 135027 they
will arrange collection of this product from you. They will then correctly dispose of the unit
and recover any materials that may be recycled and reused.
There will be no charge to you
for this service.
