Icom IC-78 Instruction Manual - Page 42

Fuse replacement, Resetting the CPU

Page 42 highlights

8 MAINTENANCE s Fuse replacement If a fuse blows or the transceiver stops functioning, try to find the source of the problem, and replace the damaged fuse with a new, rated fuse. CAUTION: DISCONNECT the DC power cable from the transceiver when changing a fuse. The IC-78 has 2 types of fuses installed for transceiver protection. • DC power cable fuses FGB 20 A • Circuitry fuse FGB 4 A DC POWER CABLE FUSE REPLACEMENT 20 A fuse CIRCUITRY FUSE REPLACEMENT The 13.8 V DC from the DC power cable is applied to all units in the IC-78 through the circuitry fuse. This fuse is installed in the MAIN unit. q Remove the top cover as shown on p. 48 w Replace the circuitry fuse as shown in the diagram at right. e Replace the top cover. PA unit FGB 4 A s Resetting the CPU [PWR] [√] [∫] Returns programmed values in both quick and initial set mode to their defaults. When first applying power or when the function seems to be displaying erroneous information, reset the CPU as follows: q Make sure transceiver power is OFF. w While pushing [UP Y] and [Z DN], push [PWR] to turn power ON. • The internal CPU is reset. 40

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40
CIRCUITRY FUSE REPLACEMENT
The 13.8 V DC from the DC power cable is applied to
all units in the IC-78 through the circuitry fuse. This
fuse is installed in the MAIN unit.
q
Remove the top cover as shown on p. 48
w
Replace the circuitry fuse as shown in the diagram
at right.
e
Replace the top cover.
FGB 4 A
PA unit
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.
CAUTION:
DISCONNECT
the DC power cable
from the transceiver when changing a fuse.
The IC-78 has 2 types of fuses installed for transceiver
protection.
•DC power cable fuses
................................
FGB 20 A
•Circuitry fuse
................................................
FGB 4 A
DC POWER CABLE FUSE REPLACEMENT
20 A
fuse
Resetting the CPU
Returns programmed values in both
quick
and
ini-
tial set mode
to their defaults.
When first applying power or when the function seems
to be displaying erroneous information, reset the CPU
as follows:
q
Make sure transceiver power is OFF.
w
While pushing [UP
Y
] and [
Z
DN], push [PWR] to
turn power ON.
•The internal CPU is reset.
[PWR]
[
][
]
8
MAINTENANCE