Icom IC-756PROII - Tuner Adjustments; CTRL-A Unit

4 - 10
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.