Harris DX 25U, Техническое руководство

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MCG Electronics, Inc.
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EFI Corp.
•
General Electric
All of these vendors provide parts and
systems to protect broadcast transmitters.
All audio and control lines should be pro-
tected the same as described for ac lines
with components sized accordingly.
All coaxial lines should have the shield
connected to the system ground at the point
of entrance and in addition have a ferrite
choke around it located between the en-
trance point and the equipment rack. This
will provide a high impedance for current
flowing in the shield but does not affect the
signal currents.
a.5.
Conclusion
The 1% chance of a major lightning strike
probably can not be protected against but
the other 99% can be controlled and damage
prevented. Install surge protection on all
incoming and outgoing lines at the wall of
the building connected to a well designed
ground system. Properly install the antenna
ground system with spark gap adjusted cor-
rectly and maintained. With this done you
can sleep peacefully at night if your bed
isn’t under the feed line.
Figure a-4. EM Flux Field
Figure a-5. Sample Surge Voltage as a Function of
Distance from Stroke to Line
a-3
WARNING: Disconnect primary power prior to servicing.