Pll Adjustments - Icom IC-7400 Service Manual

5-2 PLL ADJUSTMENTS

ADJUSTMENT ADJUSTMENT CONDITION
1 • Displayed freq. : Any
REFERENCE
FREQUENCY • Preset R1032 (RF unit) to the cen-
ter position.
• Preset L1902 (RF unit) approxi-
mate 1.5 mm downside from top of
the coil's case.
• Receiving
2 • Receiving
LPL LOCK 1 • Displayed freq. : 0.030000 MHz
• Mode
VOLTAGE
• Receiving
VCO LOCK 1 • Displayed freq. : 7.999999 MHz
• Mode
VOLTAGE
• Receiving
2 • Displayed freq. : 21.999999 MHz
• Mode
• Receiving
3 • Displayed freq. : 39.999999 MHz
• Mode
• Receiving
4 • Displayed freq. : 60.000000 MHz
• Mode
• Receiving
1LO 1 • Displayed freq. :
OUTPUT 0.500000 MHz,
LEVEL 8.000000 MHz, 21.999999 MHz
22.000000 MHz, 39.999999 MHz
40.000000 MHz, 50.000000 MHz
54.000000 MHz, 144.000000 MHz,
148.000000 MHz
• Receiving
3LO 1 • Displayed freq. : Any
OUTPUT • Mode
• Receiving
LEVEL
1 • Displayed freq. : 14.100000 MHz
MARKER
OUTPUT • Mode
LEVEL • Marker
• Receiving
MEASUREMENT
UNIT
RF
RF
: USB
RF
: USB
: USB
: USB
: USB
RF
7.999999 MHz
RF
: USB
FRONT
: CW
: ON
5 - 2
VALUE
LOCATION
Connect an RF volt- Maximum level
meter to the check (0 dB or more)
point P1901.
Connect a frequency 64.000000 MHz
counter to the check
point P1901.
Connect a digital
multimeter or oscillo-
scope to the check
point CP1101 (LV1).
Connect a digital
multimeter or oscillo-
scope to the check
point CP1801 (LV2).
Connect an RF volt- –7 dBm or more
meter to the check
point CP1500.
Connect an RF volt- –25 dBm or more
meter to the check
point CP1601.
Display S3 or more
(S-meter level)
ADJUSTMENT
POINT
UNIT ADJUST
RF L1903,
L1904,
L1901
(L1902, R1032
for critical
adjustment)
C1303
1.0 V RF
C1208
4.0 V RF
C1228
C1248
C1268
Verify
Verify
Verify