Icom IC-2710H Service Manual page 41

LOGIC UNIT (TOP VIEW)
LOGIC UNIT (BOTTOM VIEW)
+
DC power supply
+2.4
v
to MAIN UNIT
� ..- M N
_, - 0 0
§'! �
to BATIERY
�
<!l BT
1
1 0 - 3
SWITCH BOARD (TOP VIEW)
to MAIN UNIT
C O R DLESS M I C RO P H O N E ADJ U STM ENT
• PREPARATION
Disconnect the Ni-Cd battery (BT 1 ), then connect a DC power supply (2.4 V) with a dummy resistor (1
unit).
ADJUSTMENT ADJUSTMENT CONDITIONS
MICROPHONE 1 • Disconnect a power supply (2.4 V) from J 1
OUTPUT
(MAIN unit) only.
• Remove the microphone (MAIN unit,
MC1 ), then connect an audio generator
through the coupling capacitor (0.01 µF),
and set as 10 mV/1 kHz
• Connect a DC power supply (8.8 V) to
W8V line (MAIN unit, J2, pin 1 ).
• Push the [PTT] switch.
455 kHz 1 • Connect a DC power supply (2.4 V) to J 1
REFERENCE
(LOGIC unit).
FREQUENCY
• Re-set R 1 5 to the center position.
• Push the [PTT] switch.
DEVIATION 1 • Connect an audio generator to the point
(AUDIO)
between C2 and C4 (MAIN unit) through
the coupling capacitor (0.01 µ F) and set as:
1 0 mV/1 kHz
• Set a modulation analyzer as:
HPF : 50 Hz
LPF : 20 kHz
• Push the [PTT] switch.
1
DEVIATION • Push any key on the keypad.
(DATA}
2 • Make a soldering bridge at CP 5.
• Push any key on the keypad.
@.iliTI
to MAIN UNIT
O
ill 1 W)) to J1 (LOG IC
ADJUSTMENT
MEASUREM ENT
POINT
VALUE
UNIT LOCATION UNIT ADJUST
1 2 mV ± 3 dB
MAIN Connect an oscillo- MAIN
scope to J2 (WMIC}.
MAIN Connect a frequency 455.00 kHz MAIN
counter to CP1 .
MAIN Connect a modula- ±4.8 kHz MAIN
lion analyzer to
CP1 .
±7.5 kHz
MAIN Connect a modula- MAIN
lion analyzer to
±5.3 kHz
CP1 .
Verify
L1
R78
R42
R39