Icom IC-7800 Service Manual page 53

RXPLL-B UNIT ADJUSTMENTS–Continued
ADJUSTMENT ADJUSTMENT CONDITION
HPL LOCK
12 • SUB display frequency
VOLTAGE
(VCO6)
• Mode
• Receiving
S1 LO
1 • SUB display frequency
OUTPUT
• Mode
• Receiving
2LO LOCK
1 • SUB display frequency
VOLTAGE
• Mode
• Receiving
2LO
1 • MAIN display frequency
OUTPUT
• Mode
• Receiving
RX
1 Pre-set the IC-7800 as the following
SENSITIVITY
condition.
(HF)
• SUB display frequency
• Mode
• Dualwatch
• MAIN Ant.
• SUB Ant.
• Pre-amp. 1
• MAIN AF
• Receiving
2 • SUB display frequency
• Mode
• Connect an SSG to [ANT1]
connector and set as;
Frequency : 14.1515 MHz
Level
Modulation : OFF
• Receiving
IMAGE
1 • SUB display frequency
RESPONSE
• Mode
• Connect an SSG to [ANT1]
connector and set as;
Frequency : 14.0765 MHz
Level
Modulation : OFF
• Receiving
*This output level of a standard signal generator (SSG) is indicated as SSG's open circuit.
UNIT
RX
: 45.000 MHz PLL-B
: USB
RX
: 14.999 MHz PLL-B
: USB
RX
: 14.100 MHz PLL-B
: USB
RX
: 14.100 MHz PLL-B
: USB
RX
PLL-B
: 14.150 MHz
: USB
: ON
: ANT2
: ANT1
: ON
: Minimum level
Rear
: 14.150 MHz panel
: USB
: 1 µV* (–107 dBm)
Rear
: 14.150 MHz panel
: USB
: 50 mV* (–13 dBm)
MEASUREMENT
LOCATION
C o n n e c t a D C
voltmeter to CP2
(LV2).
C o n n e c t a n R F
voltmeter to J351
(S1LO).
C o n n e c t a D C
voltmeter to CP3.
Connect a spectrum
analyzer to J561 (2LO).
C o n n e c t a D C
voltmeter to CP1102.
C o n n e c t a D C
voltmeter to CP1103.
Per-set L1401, L1402,
L1403, L1404, L1405
and L1406 as the
illustration at right.
C o n n e c t a n A C
Maximum audio level
millivolt meter to [EXT
Ω
SP] jack with 8 load.
C o n n e c t a n A C
millivolt meter to [EXT
Ω
SP] jack with 8 load.
4 - 12
ADJUSTMENT
VALUE
UNIT
1.2 V–2.0 V RX
PLL-B
2.25 dBm ±0.25 dB RX
PLL-B
2.0 V ±0.3 V RX
PLL-B
Maximum level RX
(–9.0 dBm ±3.0 dB) PLL-B
4.5 V ±0.1 V RX
PLL-B
4.5 V ±0.1 V RX
PLL-B
Center RX
position PLL-B
2 rotations
RX
PLL-B
Core
3.5 rotations
RX
PLL-B
Core
Core's top
RX
PLL-B
RX
PLL-B
Minimum audio level
RX
PLL-B
POINT
ADJUST
Verify
R357
C546
Adjust
repeatedly
L565,
L566
R1101
R1132
R1228
L1401,
L1402
L1403,
L1404
L1410,
L1411
L1408,
L1058
R1516,
C1656