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RECEIVER ADJUSTMENTS—continued
RECEIVER
TOTAL GAIN
NOISE
BLANKER
SPECTRUM
SCOPE
ADJUSTMENT
ADJUSTMENT
ADJUSTMENT CONDITION
MEASUREMENT
VALUE
POINT
UNIT
LOCATION
UNIT
ADJUST
1
1
2
1
2
3
• Display freq.
: 14.100000 MHz
• [DUALWATCH] : OFF
• Mode
: USB
• Filter
: 2.4 kHz
• [AGC]
: OFF
• [P.AMP]
: OFF
• Connect an SSG to [ANT1] con-
nector and set as:
Frequency : 14.101500 MHz
Level
: 160 mV* (–3 dBm)
Modulation
:
OFF
• Receiving
• Display freq.
: 14.100000 MHz
• [DUALWATCH] : OFF
• Mode
: USB
• [AGC]
: MID
• [P.AMP]
: P.AMP1
• [NB]
: OFF
• [NB LEVEL]
: 50%
• Connect an SSG to [ANT1] con-
nector and set as:
Frequency : 14.101500 MHz
Level
: 5.6 µV* (–92 dBm)
Modulation
:
OFF
and apply following signal to [ANT1]
connector.
• Preset R271 on the MAIN-A unit to
the center position.
• Receiving
• [NB]
: ON
• Receiving
• Display freq.
: 14.100000 MHz
• Mode
: USB
• [DUALWATCH] : OFF
• [P.AMP]
: OFF
• [SCOPE]
: ON
• [SCOPE ATT]
: OFF
• Verify the connection of J2001 on
the RF-B unit and P801 (S3LO:
12.89000 MHz/–7 dBm) from the
PLL unit.
• Connect an SSG to [ANT1] con-
nector and set as:
Frequency : 14.101500 MHz
Level
: 1 µV* (–107 dBm)
Modulation
:
OFF
• Receiving
• Set an SSG output level to OFF.
• Receiving
• Set an SSG output level as:
Level
: 50 mV* (–13 dBm)
• Receiving
MAIN-A
MAIN-A
RF-B
Connect an oscil-
loscope to the check
point CP213.
Connect an oscil-
loscope to the check
point CP271.
Connect a digital
multimeter or oscil-
loscope to the check
point CP2002.
3.7 Vp-p
Maximum noise level
At the point where the
voltage just reduces.
Maximum voltage
0.1 V
4.4 V
MAIN-A
MAIN-A
RF-B
R210
L271,
L272,
L273
R271
L2102,
L2201,
L2202
R2012
R2016
100 msec.
1 msec.
*This output level of a standard signal generator (SSG) is indicated as SSG’s open circuit.