Yaesu FT-847 Operating Manual page 9

Tips for Successful
Mobile Installations:
r Before connecting the DC cable to the battery, mea-
sure the voltage across the battery terminals with
the engine running fast enough to show a charge. If
the voltage is above 15 Volts, the vehicle's voltage
regulator should be adjusted to reduce the charg-
ing voltage to 14 Volts or lower.
r Route the DC cable as far away from the ignition
cables as possible, and cut off any excess cable
(from the battery end) to minimize voltage drop.
r If the DC cable is not long enough, use #12 AWG
(minimum) stranded, insulated wire to extend it.
Be certain to solder the connections at the splice
securely, and provide ample insulation for the sol-
dered splice (heat shrink tubing plus black electri-
cal tape work well).
r Be sure that the POWER switch on the FT-847 is
OFF when connecting the DC cable's connector
to the rear panel 13.8VDC jack.
r Be sure that the POWER switch on the FT-847 is
OFF when starting your car. There initially may
be no voltage regulation, which may cause erratic
operation of your transceiver's microprocessor.
r Check the battery terminal connections frequently
to be sure they are tight and not corroded.
FT-847 O
PERATING
P C
OWER
M
ANUAL
ONNECTIONS
Permanent damage can result if improper sup-
ply voltage, or reverse-polarity voltage, is ap-
plied to the FT-847. The Limited Warranty on
this transceiver does not cover damage caused
by application of AC voltage, reversed polarity
DC, or DC voltage outside the specified range
of 13.8V ±10%.
When replacing fuses, be certain to use a fuse
of the proper rating. The FT-847 requires a 25A
fast-blow fuse.
Installation
Caution
7