Icom IC-R75, Руководство по обслуживанию

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4-3 RECEIVER ADJUSTMENTS
4 - 4
RECEIVER
SENSITIVITY
1ST MIXER
BALANCE
ADJUSTMENT
ADJUSTMENT ADJUSTMENT CONDITION
MEASUREMENT
VALUE
POINT
UNIT LOCATION UNIT ADJUST
1
2
1
• Displayed frequency
: 14.10000 MHz
• Mode : USB
• PREAMP1 : ON
• ANT select : ANT1
• AGC : FAST
• NOISE BLANKER : OFF
• RF/SQL
: CENTER
• PBT1/PBT2 : CENTER
• IF FILTER1 : 2.4 kHz
• IF FILTER2 : 2.4 kHz
• Connect an SSG to the antenna
connector1 and set as:
Frequency : 14.10150 MHz
Level : 22 µV*
(–13 dBµ)
Modulation : OFF
• Receiving
• Displayed frequency
: 0.10000 MHz
• PREAMP1 : OFF
• set an SSG level as
: OFF
• Receiving
Rear
Panel
Rear
panel
Connect the AC
milli-volt meter to
the [EXT SP] jack
with an 8
Ω
load.
Connect an oscillo-
scope to the [EXT
SP] jack with 8
Ω
load.
Pre-set to center
Maximum output level
Minimum noise level
MAIN
MAIN
MAIN
R444
R898
L443,
L461,
L462,
L471,
L701,
L711,
L712,
L891,
L892,
L911
L443,
R444
*This output level of the standard signal generator (SSG) is indicated as SSG’s open circuit.
Receiver sensitivity adjustment
Pre-set to center before
receiver sensitivity adjustment
1st mixer balance adjustment
EXT SP JACK
Receiver sensitivity and 1st mixer balance
check point
• MAIN UNIT
R893
R444
L701
L711
L712
L471
L462
L461
L443
L891
L892
L911
R444
L443