Pa Unit Adjustments - Icom IC-703 Service Manual

4-6 PA UNIT ADJUSTMENTS

ADJUSTMENT ADJUSTMENT CONDITION
1 • Turn R159, R164 (on the PA unit) to
IDLING
CURRENT maximum counterclockwise posi-
tion.
2 • Display frequency: 14.10000 MHz
• Mode
• [MIC GAIN]
• Transmitting
3 • Transmitting
SWR • Display frequency: 14.10000 MHz
1
DETECTION • Mode
• [MIC GAIN]
• Connect CP2711 on the MAIN unit
to ground.
• Connect an audio generator to
[MIC] connector and set as:
1.5 kHz/30 mV
• Transmitting
• Transmitting
2
3
After remove the jumper wire from CP2711 on the MAIN board.
MEASUREMENT
UNIT
PA
: USB
: 1 (minimum)
Rear
: USB Panel
: 5
PA
4 - 12
LOCATION
Connect a digital 0.5 V
multimeter to check
point CP151.
Connect a DC 0.2 A increase from that
ammeter between R159 is in maximum
the DC power supply counterclockwise posi-
and transceiver's DC tion.
power socket (W80
on the PA unit).
0.2 A increase from
step 1.
Connect an RF 10 W
power meter to
[ANT1] connector.
Connect a digital Minimum voltage
multimeter to check
point CP41.
ADJUSTMENT
POINT
VALUE
UNIT ADJUST
PA
Quick
set
mode
PA
R150
R159
R164
MIC
GAIN
C561