Icom ic-775 Service Manual page 30

RECEIVER
ADJUSTMENT
(CONTINUED)
ADJUSTMENT
ADJUSTMENT CONDITIONS
MEASUREMENT
VALUE
ADJUSTMENT
POINT
UNIT
LOCATION
UNIT
ADJUST
DUALWATCH
1
.
[SPLIT!
;
ON
•
Main
frequency readout
:
14.1
00000
MHz
•
Mode
USB
.
[PREAMP/ATT]
:
OFF
.
[ANT]
:
1
•
Connect a
standard
signal
generator
to
[ANTI]
and
set as:
Frequency: 14.101500
MHz
Level
: 1
jiV
* (-1
07
dBm)
Rear
panel
Connect an
AC
millivolt-
meter
to
[EXT
SP] jack
with
an
8
Q
dummy
load.
Maximum
audio
output
level
RF
L16
2
•
Main
frequency readout
:
1
00 kHz
•
Apply no
signal to the
antenna
connector.
Minimum
noise
level
R24
PREAMP
2
1
•
Displayed frequency: 23.000000
MHz
.
Mode
:
USB
.
(PREAMP/ATT]
:
PRE
2
.
[ANT]
:
1
•
Connect a standard
signal
generator
to
[ANTI]
and
set as:
Frequency: 23.001500
MHz
• Receiving
Rear
panel
Connect an
AC
millivolt-
meter
to
(EXT SP]
jack
with
an 8
fi
dummy
load.
Maximum
audio
output level
RF
L80
NOTCH
1
•
Same
settings as
"AGC VOLTAGE"
• [NB]
:
OFF
•
[NOTCH]
:
ON
•
Connect a standard
signal
generator
to
[ANTI]
and
set as:
Frequency:
14.101500
MHz
Level
:
1
0
mV
*
(-27
dBm)
Front
panel
S/RF
meter
Minimum
level
Front
panel
[NOTCH]
control
2
Minimum
level
(-45
dB
or
more
from Notch
OFF)
IF
Cl
25,
R193
NOISE
BLANKER
1
•
Same
setting
as
"AGC VOLTAGE"
.
[NB WIDE]
:
OFF
.
[PREAMP/ATTj
:
OFF
•
Connect a
standard
signal
generator
to
[ANTI] and
set as:
Frequency: 14.101500
MHz
Level
:
1
0
pV
*
(-87
dBm)
Add
the following signal into the signal
generator
output.
-HH-
1
msec.
IF
Connect an
oscilloscope
to
CP2.
Maximum
voltage
IF
L9, L10,
L11
METER
SCALE
1 •
[RF]
Max. clockwise
•
[SQL]
:
3
o'clock position
• Receiving
Front
panel
S/RF meter
S9 + 30
dB
DIS-
PLAY
R3
S-METER
1
•
Same
setting as
"AGC VOLTAGE"
.
[PREAMP/ATT]
:
OFF
•
Connect a
standard signal
generator
to
[ANT
1]
and
set as:
Level
:
50
pV
* (-73
dBm)
Front
panel
S/RF
meter
S9
IF
R386
2
•
Set the standard
signal generator as:
Level
:
50
mV
*
(-13
dBm)
S9 + 60 dB
R453
FM SQUELCH
1
• Displayed frequency
:
29.100000
MHz
•
Mode
FM
.
[PREAMP/ATT]
:
PRE
2
•
Apply
no
signal to
the antenna connector.
Top
panel
Speaker Squelch
just
closes.
Front
panel
[SQL]
control
2
•
Connect a
standard signal
generator
to
[ANTI] and
set as:
Frequency: 29.100000
MHz
Level
:
0.16
pV
*
(-123
dBm)
Squelch
just
opens.
R233
*
This output level of
the standard
signal
generator
(SSG)
is
indicated as
SSG's open
circuit.
5-6