5 - 3
5-3 PLL ADJUSTMENT
PLL LOCK
VOLTAGE
PLL
REFERENCE
FREQUENCY
1
2
3
4
1
• Operating frequency : 136.000 MHz
• Receiving
• Operating frequency : 174.000 MHz
• Receiving
• Operating frequency : 136.000 MHz
• Transmitting
• Operating frequency : 174.000 MHz
• Transmitting
• Operating frequency : 174.000 MHz
• Transmitting
MAIN
Rear
panel
Connect a digital multi-
meter or an oscillo-
scope to the check
point, “LV”.
Loosely couple a fre-
quency counter to the
antenna connector.
3.0 V
10.0–14.0 V
3.0 V
10.5–15.5 V
174.00000 MHz
MAIN
MAIN
L38
Verify
L43
Verify
R376
ADJUSTMENT
ADJUSTMENT CONDITIONS
UNIT
LOCATION
VALUE
UNIT
ADJUST
MEASUREMENT
ADJUSTMENT
L.V.
PLL lock voltage
check point
L38
Rx PLL lock voltage
adjustment
L43
Tx PLL lock voltage
adjustment
R376
Reference frequency
adjustment
• MAIN UNIT