15
Consult the dealer or an experienced Radio/TV technician for help.
The user is cautioned that any changes or modifications not expressly approved by the party
responsible for compliance could void the user‘s authority to operate the equipment. The user
is also cautioned that any peripheral device installed with this equipment must be connected
with a high-quality shielded cable to insure compliance with FCC limits.
Note 2: The shield of the cable, whether foil, braid, braid over foil, or double braid, must be
properly terminated (connected) 360 to the connector. This is usually accomplished by the
use of a metal or metalized plastic back shell, but may be implemented by direct contact,
including soldering, with metal portion of connector. Experience has indicated that cable
assemblies (with connectors) advertised as ―shielded‖ are not necessarily terminated properly,
if terminated at all. Check cable construction to be sure.
RFI Suppression
In moving to the world of digital communications via computers, a new dimension of RFI may be
encountered. In spite of the equipment manufacturers‘ diligence, each new piece of electronic
equipment will react differently in each separate environment. Every amateur station will have its
own unique layout, equipment variation, and antenna installations. Experience has shown that
these differences are related to the total RF environment, and may be causative factors in RFI
induced problems. The suggestions given here may assist in resolving RFI problems you may
encounter in your ―unique‖ station.
Use shielded cable for all connections between equipment.
Make all interconnecting cables as short as practical. A balance should be maintained
between cable length and equipment proximity. At times simply moving the video monitor
one foot further from an interface or other device will solve a ―screen hash‖ problem.
Antenna runs should be kept away from equipment control lines and/or interconnecting
cables. If it is necessary for such lines to cross each other they should do so at 90-degree
angles.
Ground leads should be as short as possible and go to a GOOD EARTH GROUND.
Interconnecting cables appearing to act as radiators or antennas should be looped through
a toroid. Be certain toroids, if used, are designed for the frequency in use.
To Next Page
Loading...
