Receiver Adjustments - Icom IC-M700PRO Servise Manual

4-4 RECEIVER ADJUSTMENTS

ADJUSTMENT ADJUSTMENT CONDITION
RECEIVER
1 • Display frequency : 2.1820 MHz
GAIN
• Mode
• Noise blanker
• Squelch
• Speaker
• AGC
• RF gain
• R223 (MAIN unit) : Max. clockwise
• R257 (MAIN unit) : Max.counter
• R300 (MAIN unit) : Center
• C o n n e c t a s t a n d a r d s i g n a l
generator to the [ANT] connector
and set as:
Frequency
Level
modulation
• Receiving
CLARITY
1 • While pushing the [SQL] and [CL]
switches, turn power ON.
TOTAL GAIN
1 • Display frequency : 12.2300 MHz
• Mode
• C o n n e c t a s t a n d a r d s i g n a l
generator to the [ANT] connector
and set as:
Frequency
Level
modulation
• Receiving
2 • Set the signal generator to OFF (no
output).
S-METER
1 • While pushing the [SQL] and [T
ONLY] switchs, turn power ON.
• Display frequency : 12.2300 MHz
• Mode
2 • C o n n e c t a s t a n d a r d s i g n a l
generator to the [ANT] connector
and set as:
Frequency
Level
• Receiving
NOISE
1 • Display frequency : 12.2300 MHz
BLANKER
• Mode
• C o n n e c t a s t a n d a r d s i g n a l
generator to the [ANT] connector
and set as:
Frequency
Level
Add the following signal into
the signal generator output.
1 msec.
• Receiving
This output level of the standard signal generator (SSG) is indicated as SSG's open circuit.
: J3E
: OFF
: OFF
: OFF
: ON
: 9
clockwise
: 2.1815 MHz
: 0.5 µV
(–113 dBm)
: OFF
: J3E
: 12.2315 MHz
: 0.32 mV
(–57 dBm)
: OFF
: J3E
: 12.2315 MHz
: 1 mV
(–47 dBm)
: J3E
: 12.2315 MHz
: 3.2 µV
(–97 dBm)
100 msec.
MEASUREMENT
UNIT LOCATION
Rear C o n n e c t a n A C
Panel millivoltmeter to the
[EXT SP] jack with a
4 dummy load.
Set the [CLARITY] control to the center position and
push the [DIMMER] switch.
Rear C o n n e c t a n A C
Panel millivoltmeter to the
[EXT SP] jack with a
4 ohms dummy load.
Function S/RF meter
display
MAIN C o n n e c t a n
oscilloscope to R59.
4 - 8
ADJUSTMENT
VALUE
UNIT
Muximum output level MAIN
Front
Panel
1.0 V Front
Panel
–30 dB (32 mV) MAIN
Push the [DIMMER] Font
switch. Panel
7th dot just appears
while pushing the
[DIMMER].
1 2 3 4
MAIN
Adjust the maximum
noise wave displayed
on the oscilloscope.
POINT
ADJUST
Adjust in
sequence
L74, L75,
L78, L79,
L83, L84,
L85, L92,
L93
[CLARITY]
[VOLUME]
R223
[DIMMER]
Verify
L80, L81