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10.
S meter sensitivity
26
(1)
(2)
(3)
Purpose:
Adjust the pointer of S meter to SO with specified
input.
Measuring instrument:
SSG
Adjusting procedures:
1)
Check that the RF GAIN
VR
(VR2)
is set to
fully clockwise position.
2)
Set
the
BAND
to
14MHz
and
apply
a
14.2MHz
30dB
SSG
signal
from
the
REC
ANT
terminals
and
establish
the tuning
of
DRIVE and VFO (signal is not modulated).
3)
Adjust
the
SENS!
VR
(VR2}
of S meter
mounted
on the unit X48-0012-00 so that the
deflection of S meter will point to S9.
4)
Set the RF GAIN VR (VR2)} to fully counter-
clockwise position.
5)
Turn
the
VR
attached
to the SM
terminal
disposed at the rear of the IF unit to locate
the pointer of S meter at the first portion of
letter "mA" located near its full scale.
6}
Again, set the RF GAIN
VR
to fully clock-
wise
position
and
check
that
the meter
is
pointing to S9.
{Note]
After
completing
the abovementioned
adjust-
ment, check for "'leak of carrier'.
The
"leak
of
carrier'
must
be
checked
by
following
procedure
since it sometimes
occurs,
depending
on the carrier position or the wave
form unbatance of the filter (X-1).
e After
finishing
the
adjustment
by 8-(3)-3),
rotate the RF GAIN
VR counterclockwise slowly
and hold it at a point just before the indication of
S meter increases beyond SQ.
e Next, turn off the SSG output and check that
the S meter gives an indication of more than S7.
e Place
the
RF
GAIN
VR
in fully
clockwise
position.
11.
RIT
(1)
(2)
(3)
Purpose:
To adjust the transmitting frequency to the center
(zero point) of the RIT knob.
Measuring instruments:
1)
AF generator
2)
Oscilloscope
Adjusting procedures:
1)
Set the function of the oscilloscope to EXT
HORIZONTAL
and
introduce
the
output
(1kHz, 1V) of AF generator to the H termi-
nal.
2)
Set the
RIT
knob
(VR3
on
the surface of
panel) to exactly ''O" and pull the RF GAIN
VR switch out.
3)
Receive the marker at 14.2MHz and obtain a
beat
sound
of about
ikHz.
In this case, a
signal
must
be
received
with
a maximum
sensitivity by adjusting the knobs at respective
stages.
4)
Introduce
the
received
output
to
the
V
terminal
of oscilloscope and adjust the VFO
dial finely until the Lissajous' figure stops.
In
this case, the figure should be a circle.
5)
Push in the RF GAIN VR knob to set the RIT
to off and adjust the RIT ''0'' ADJ VR (VR2)
on
the
unit
X43-0010-00
so that
the
Lis-
sajous' figure of the oscilloscope will become
a circle again.
[Note]
The adjustment of Item 5) must be finished with
one
minute.
If it cannot
be made within this
period, readjustment must be made from
Item 4).
6)
Set the marker to 'OFF' and then disconnect
the AF generator and the oscilloscope.
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