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4 - 6
RXPLL-A UNIT ADJUSTMENTS–Continued
HPL LOCK
VOLTAGE
(VCO6)
R1 LO
OUTPUT
2LO LOCK
VOLTAGE
R2 LO
OUTPUT
T2 LO
OUTPUT
RX
SENSITIVITY
(HF)
ADJUSTMENT
ADJUSTMENT
ADJUSTMENT CONDITION
MEASUREMENT
VALUE
POINT
UNIT
LOCATION
UNIT
ADJUST
12
1
1
1
1
1
2
• MAIN display frequency
: 45.000 MHz
• Mode
: USB
• Receiving
• MAIN display frequency
: 14.999 MHz
• Mode
: USB
• Receiving
• MAIN display frequency
: 14.100 MHz
• Mode
: USB
• Receiving
• MAIN display frequency
: 14.100 MHz
• Mode
: USB
• Receiving
• MAIN display frequency
: 14.100 MHz
• Mode
: USB
• Receiving
Pre-set the IC-7800 as the following
condition.
• MAIN display frequency
: 14.150 MHz
• Mode
: USB
• Dualwatch
: OFF
• MAIN Ant.
: ANT1
• Pre-amp. 1
: ON
• SUB AF
: Minimum level
• Receiving
• MAIN display frequency
: 14.150 MHz
• Mode
: USB
• Connect an SSG to [ANT1]
connector and set as;
Frequency : 14.1515 MHz
Level
: 1 µV* (–107 dBm)
Modulation
:
OFF
• Receiving
RX
PLL-A
RX
PLL-A
RX
PLL-A
RX
PLL-A
RX
PLL-A
RX
PLL-A
Rear
panel
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
vo l t m e t e r t o J 3 5 1
(R1LO).
C o n n e c t a D C
voltmeter to CP3.
Connect a spectrum
a n a l y ze r t o J 8 3 1
(R2LO).
Connect a spectrum
a n a l y ze r t o J 5 6 1
(T2LO).
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
millivolt meter to [EXT
SP] jack with 8
Ω
load.
1.2 V–2.0 V
2.25 dBm ±0.25 dB
2.0 V ±0.3 V
Maximum level
(–10 dBm ±3.0 dB)
Maximum level
(3.0 dBm ±3.0 dB)
4.5 V ±0.1 V
4.5 V ±0.1 V
Center
position
Maximum audio level
RX
PLL-A
RX
PLL-A
RX
PLL-A
RX
PLL-A
RX
PLL-A
RX
PLL-A
RX
PLL-A
RX
PLL-A
RX
PLL-A
RX
PLL-A
RX
PLL-A
RX
PLL-A
Verify
R357
C546
L801,
L834
Adjust
repeatedly
L565,
L566
R1101
R1132
R1228
L1401,
L1402
L1403,
L1404
L1410,
L1411
L1408,
L1058
*This output level of a standard signal generator (SSG) is indicated as SSG’s open circuit.
Core
2 rotations
Core
3.5 rotations
Core's top