15
FT-857 Operating Manual
I
NSTALLATION
E
LECTROMAGNETIC
C
OMPATIBILITY
If this transceiver is used with, or in the vicinity of, a computer or computer-driven accesso-
ries, you may need to experiment with grounding and/or Radio Frequency Interference (RFI)
suppression devices (such as ferrite cores) to minimize interference to your communications
caused by energy from the computer. Computer-generated RFI is usually a result of inad-
equate shielding of the computer’s cabinet or I/O and peripheral connections. While com-
puter equipment may “comply” with RF emission standards, this does not ensure that sensi-
tive Amateur Radio receivers like the
FT-857
will not experience interference from the
device!
Be certain to use only shielded cables for TNC-to-Transceiver connections. You may need
to install AC line filters on the power cord(s) of the suspected equipment, and decoupling
ferrite toroidal chokes may be required on interconnecting patch/data cables. As a last re-
sort, you can try installing additional shielding within the computer’s case, using appropri-
ate conductive mesh or conductive shielding tape. Especially check “RF holes” where plas-
tic is used for cabinet front panels.
For further information, consult amateur radio reference guides and publications relating to
RFI suppression techniques.
H
EAT
AND
V
ENTILATION
To ensure long life of the components, be certain to provide adequate ventilation around the
cabinet of the
FT-857
. The cooling system of the transceiver must be free to draw cool air in
from the side of the transceiver and expel warm air from the rear of the transceiver.
Do not install the transceiver on top of another heat-generating device (such as a linear
amplifier), and do not place equipment, books, or papers on top of the transceiver. Place the
transceiver on a hard, flat, stable surface. Avoid heating vents and window locations that
could expose the transceiver to excessive direct sunlight, especially in hot climates.
Heat
Water & Moisture
Dust
Ventilation