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