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4 - 4
4-3 TRANSMITTER ADJUSTMENTS
ADJUSTMENT
ADJUSTMENT CONDITION
MEASUREMENT
VALUE
ADJUSTMENT
POINT
UNIT
LOCATION
UNIT
ADJUST
IDLING
CURRENT
(for drive)
1
• Display freq.
: 14.100000 MHz
• Mode
: CW (Key up)
• Preset R11, R18 on the PA unit to
max. CCW
• [RF POWER]
: Max. CW
• [TUNER]
: OFF
• Transmitting (without key)
PA
Unsolder W29.
Connect an ammeter to
the unsoldering points
of W29.
250 mA
PA
R11
After adjustment, re-solder the wire (W29) on the PA board
(for fi nal
amplifi er)
2
• Transmitting (without key)
PA
U n s o l d e r R 2 8 ( L 8
side).
Connect an ammeter to
the unsoldering points
of R28.
500 mA
PA
R18
After adjustment, re-solder the wire (W29) on the PA board
TX PEAK
1
• Display freq.
: 14.100000 MHz
• Mode
: USB
• Set following selections, controls
and functions as :
[VOX] : OFF
, [ TX] : OFF
PBT1 : Center , PBT2 : Center
Filter
: 2.4 kHz
[RF POWER] : Max. CW
[MIC GAIN] : Center
[TUNER]
:
OFF
[METER]
: METER Po
[MONITOR]
:
OFF
• Apply no audio signals to [MIC]
connector.
• Transmitting
MAIN-A C o n n e c t a d i g i t a l
multimeter or oscil-
loscope to the check
point CP243.
0.06 V
MAIN-A
R247
2
• Connect an audio generator to
[MIC] connector and set as:
Frequency : 1.5 kHz
Level
: 1 mVrms
• Transmitting
Rear
panel
Connect an RF power
meter to [ANT1] con-
nector.
50 W
Front
panel
[MIC GAIN]
control
3
• Transmitting
Maximum output
power
MAIN-A
L261
4
• [MIC GAIN]
: Center
• Preset L1701, L1702's top to same
high with coil's case.
• Connect an audio generator to
[MIC] connector and set as:
Frequency : 1.5 kHz
Level
: 10 mVrms
• Transmitting
RF-B
Connect an RF volt-
meter the check point
J201.
Maximum level
RF-B
L1801,
L1553,
L1702,
L1701
Adjust in sequence L1801, L1553, L1702, L1701, L1702, L1701
TRANSMITTER
TOTAL GAIN
1
• Display freq.
: 14.100000 MHz
• Mode
: USB
• [MIC GAIN]
: Center
• Connect an audio generator to
[MIC] connector and set as:
Frequency : 1.5 kHz
Level : 1 mVrms
• Transmitting
Rear
panel
Connect an RF power
meter to [ANT1] con-
nector.
50 W
MAIN-A
R263