Icom IC-7800 Service Manual Addendum page 395

4-8 SCOPE UNIT ADJUSTMENTS
ADJUSTMENT ADJUSTMENT CONDITION
1 Pre-set the IC-7800 as the following
S3 LO LOCK
VOLTAGE condition.
• MAIN display frequency
• Mode
• Dualwatch
• Pre-amp.
• Attenuator
• Scope
• Scope attenuator: OFF
• Span
• Receiving
SCOPE 1 • Connect an SSG to [ANT1] connec-
tor and set as;
Frequency : 14.200 MHz
Level
Modulation : OFF
• Receiving
2 • Connect an SSG to J1 and set as;
Frequency : 71.715 MHz
Level
Modulation : OFF
• Receiving
3 • Connect an SSG to [ANT1] connec-
tor and set as;
Frequency : 14.200 MHz
Level
Modulation : OFF
• Receiving
SCOPE GAIN 1 • MAIN display frequency
• Mode
• Connect an SSG to [ANT1] connec-
tor and set as;
Frequency : 14.200 MHz
Level
Modulation : OFF
• Receiving
1 • MAIN display frequency
SCOPE
ATTENUATOR
• Mode
• Scope attenuator: 30 dB
• Connect an SSG to [ANT1] connec-
tor and set as;
Frequency : 14.200 MHz
Level
Modulation : OFF
• Receiving
*This output level of a standard signal generator (SSG) is indicated as SSG's open circuit.
UNIT
SCOPE
: 14.200 MHz
: CW
: OFF
: OFF
: OFF
: ON
: ±25 kHz
Front
panel
: 500 µV* (–53 dBm)
: 100 mV* (–7 dBm)
: 500 µV* (–53 dBm)
Front
: 14.200 MHz panel
: CW
: 500 µV* (–53 dBm)
Front
: 14.200 MHz panel
: CW
: 500 µV* (–53 dBm)
MEASUREMENT
LOCATION
Connect a digital volt-
meter to CP801.
Scope wave on the
LCD.
Set peak of scope
Scope wave on the
wave form to 6 scales
LCD.
in the scope screen
Set peak of scope
Scope wave on the
wave form to 3 scales
LCD.
in the scope screen.
4 - 22
ADJUSTMENT
VALUE
UNIT
2.5 V
SCOPE
Maximum wave form
SCOPE
Minimum wave form
Maximum wave form
SCOPE
SCOPE
POINT
ADJUST
C824
Adjust in
sequence
L203,
L202,
L201,
L5,
L6,
C41,
and
repeatedly
adjust L5,
L6 and
C41 in
sequence.
C41
Adjust
L5,
L6,
repeatedly.
R416
R11