I Fuse Replacement; I Tuning Dial Brake Adjustment - Icom IC-746PRO Instruction Manual

13
MAINTENANCE
PROBLEM
The displayed frequency
does not change properly.

I Fuse replacement

If a fuse blows or the transceiver stops functioning, try
to find the source of the problem, and replace the dam-
aged fuse with a new, rated fuse.
The IC-746PRO has 2 types of fuses installed for
transceiver protection.
• DC power cable fuses ................................ FGB 30 A
• Circuitry fuse ................................................ FGB 5 A
D D DC power cable fuse replacement
Refer the figure illustrated at right for the DC power
cable fuse replacement.
D D Circuitry fuse replacement
The 13.8 V DC from the DC power cable is applied to
all units in the IC-746PRO, except for the power am-
plifier, through the circuitry fuse. This fuse is installed in
the PA unit.
q Remove the top cover as shown on p. 90.
w Remove the 11 screws from the PA shielding plate,
then remove the plate.
e Replace the circuitry fuse as shown in the diagram
at right.
r Replace the PA shielding plate and top cover.

I Tuning dial brake adjustment

The tension of the tuning dial may be adjusted to suit
your preference.
The brake adjustment screw is located on the right
side of the tuning dial. See the figure at right.
Turn the brake adjustment screw clockwise or counter-
clockwise to obtain a comfortable tension level while
turning the dial continuously and evenly in one direction.
93
POSSIBLE CAUSE
• The dial lock function is activated.
• A set mode screen is selected.
• The internal CPU has malfunctioned.
SOLUTION
• Push [LOCK/SPCH] to turn the function OFF.
• Push [MENU] several times to exit the set
mode.
• Reset the CPU.
CAUTION:
DISCONNECT the DC power cable
from the transceiver when changing a fuse.
30 A
fuse
Light
Heavy
REF.
p. 53
—
p. 94
Fuse