Connection Of Antenna And Power Cables - Yaesu FT-991 Operating Manual

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onnection oF
Please follow the outline in the illustration regarding the proper connection of antenna coaxial cables, as well as the DC
power cable. The DC power connector for the FT-991 must only be connected to a DC source providing 13.8 Volts DC (±15
%), and capable of at least 23 Amperes of current. Always observe proper polarity when making DC connection:
The RED DC power lead connects to the Positive (+) DC terminal.
The BLACK DC power lead connects to the Negative (–) DC terminal.
To prevent damage from
lightning, atmospheric elec-
tricity, electrical shock etc., please
provide a good earth ground.
U s e a s h o r t ,
t h i c k , b r a i d e d
c a b l e t o c o n -
nect your station
equipment to the
buried ground rod (or alternative earth
ground system).
We recommend the use of the FP-1030A (USA market only) AC Power Supply. Other models of power supplies may
be used with the FT-991, but the 13.8 VDC input voltage, 23 Ampere current capability, and DC cable polarity guide-
lines described above must be strictly followed.
Note that other manufacturers may use the same type of DC power connections as the FT-991 transceiver; however, the
wiring configuration may be different from that specified for the FT-991 transceiver. Serious damage can be caused if
improper DC connections are made; consult with a qualified service technician when in doubt.
High RF voltage is present in the TX RF section of the transceiver while transmitting.
Absolutely! Do not touch the TX RF section while transmitting.
Permanent damage can result when improper supply voltage, or reverse-polarity voltage, is applied to the FT-
991. The Limited Warranty on this transceiver does not cover damage caused by application of AC voltage, re-
verse polarity DC, or DC voltage outside the specified range of 13.8 V ±15 %. When replacing fuses, be certain
to use a fuse of the proper rating. The FT-991 requires a 25 Amp blade fuse.
n :
ote
 Do not place the FT-991 in a location with direct exposure to sunshine.
 Do not place the FT-991 in a location exposed to dust and/or high humidity.
 Ensure adequate ventilation around the FT-991, to prevent heat build-up and possible reduction of performance due
to high heat.
 Do not install the FT-991 on an unstable desk or table. Do not place it in a location where objects may fall onto it
from above.
 To minimize the possibility of interference to home entertainment devices, take all precautionary steps including
separation of TV/FM antennas from Amateur transmitting antennas to the greatest extent possible, and keep trans-
mitting coaxial cables separated from cables connected to home entertainment devices.
 Ensure that the DC power cord is not subject to undue stress or bending, which could damage the cable or cause it to
be accidentally unplugged from the rear panel DC IN jack.
 Be certain to install your transmitting antenna(s) so they cannot possibly come in contact with TV/FM radio or other
antennas, or with power or telephone lines.
F T-991 O
peraTing
A
ntennA And
M
anual
b Y
efore
p c
oWer AbleS
rating (+13.8 V, 23 A) of the
power supply before con-
necting to the transceiver.
b
ou eGin
Check the DC volt-
a g e a n d c u r re n t
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