Adjustments On The Osc Unit And Pll Unit - Icom IC-7700 Service Manual

4-2 ADJUSTMENTS ON THE OSC UNIT AND PLL UNIT

ADJUSTMENT ADJUSTMENT CONDITION
REFERENCE 1 • Reference signal source :
SIGNAL LEVEL
• Receiving
REFERENCE 1 • Receiving
SIGNAL LEVEL
(40MHz)
HPL 1 • Frequency
LOCK VOLTAGE • Mode
(VCO1) • Receiving
(VCO2) 2 • Frequency
• Mode
• Receiving
(VCO3) 3 • Frequency
• Mode
• Receiving
(VCO4) 4 • Frequency
• Mode
• Receiving
(VCO5) 5 • Frequency
• Mode
• Receiving
(VCO6) 6 • Frequency
• Mode
• Receiving
1st LO 1 • Frequency
OUTPUT LEVEL • Mode
• Receiving
2nd LO 1 • Frequency
LOCK VOLTAGE • Mode
• Receiving
RX 2nd LO 1 • Frequency
LEVEL • Mode
• Receiving
TX 2nd LO 1 • Frequency
LEVEL • Mode
• Transmitting
1) C o n n e c t a n S t a n d a r d S i g n a l
External Generator to J1071 ([EXT-REF I/O]
terminal on the rear panel) and set
as;
Frequecy
Level
Modulation : None
2) Connect a Spectrum Analyzer to
J1072.
3) Adjust the REF signal level with
L1061 and L1062.
1) Connect a Spectrum Analyzer to
CP701 (PLL UNIT).
2) Adjust the REF signal (40 MHz)
level with L702 and L703.
: 7.999 MHz 1) Connect a Digital multimeter to CP2
: USB "LV2" (PLL UNIT).
2) Adjust the lock voltage with C222.
: 14.999 MHz 1) Connect a Digital multimeter to CP2
: USB "LV2" (PLL UNIT).
2) Adjust the lock voltage with C232.
: 21.999 MHz 1) Connect a Digital multimeter to CP2
: USB "LV2" (PLL UNIT).
2) Adjust the lock voltage with C242.
: 29.999 MHz 1) Connect a Digital multimeter to CP2
: USB "LV2" (PLL UNIT).
2) Adjust the lock voltage with C252.
: 44.999 MHz 1) Connect a Digital multimeter to CP2
: USB "LV2" (PLL UNIT).
2) Adjust the lock voltage with C262.
: 60.000 MHz 1) Connect a Digital multimeter to CP2
: USB "LV2" (PLL UNIT).
2) Adjust the lock voltage with C272.
: 14.999 MHz 1) Connect a Spectrum Analyzer to
: USB J351 "1LO" (PLL UNIT).
2) Adjust the output level with R357.
: 14.100 MHz 1) Connect a Digital multimeter to CP3
: USB "LV3" (PLL UNIT).
2) Adjust the lock voltage with C546.
: 14.100 MHz 1) Connect a Spectrum Analyzer to
: USB J831 "R2LO" (PLL UNIT).
2) Adjust the output level with L801
and L834.
: 14.100 MHz 1) Connect a Dummy Load to [ANT1].
: USB 2) Connect a Spectrum Analyzer to
J561 "T2LO" (PLL UNIT).
3) Adjust the output level with L565
and L566.
4 - 3
OPERATION
: 10.000 MHz
: –10.0 dBm
ADJUSTMENT
VALUE
POINT
L1061, L1062
Maximum
(OSC UNIT)
level
(repeatedly)
L702, L703
Maximum
(PLL UNIT)
level
(repeatedly)
C222
3.9–4.1 V
(PLL UNIT)
C232
3.9–4.1 V
(PLL UNIT)
C242
3.9–4.1 V
(PLL UNIT)
C252
3.9–4.1 V
(PLL UNIT)
C262
3.9–4.1 V
(PLL UNIT)
C272
3.9–4.1 V
(PLL UNIT)
R357
2.35–2.85
dBm
(PLL UNIT)
C546
1.7–2.3 V
(PLL UNIT)
Max. level
L801, L834
(–20.0
(PLL UNIT)
dBm ±3.0
(repeatedly)
dB)
L565, L566
Max. level
(PLL UNIT) (3.0 dBm
±3.0 dB)
(repeatedly)