Sony AV-3600 Service Manual page 41

Procedure B:
If
the
SONY
Alignment Tape
is
not
available,
proceed as follows.
1.
Set
up
the E-to-E
mode
with no input
signal.
2.
Connect
the
scope
CHANNEL
1
input to
TP-302
and
CHANNEL
2
to
TP-105.
3.
Set
the scope
MODE
Switch
to
ALTER
and
TRIGGERING COUPLING
to
AUTO.
4.
Set
R
1
37 (White Clip) fully
count
erlock wise.
5.
Adjust
R126
(Sync Tip
Carrier Freq.) for a stable
trace
of
3.2
MHz.
(Refer
to
Step 6 in
Procedure
A).
6.
Note
the position
(
dc voltage
level)
of the trace
on
CHANNEL
2 with reference
to
the trace
on
CHANNEL
1
(as
obtained
in
Step
5).
See
Fig. 5-2a.
This trace indicates the
dc
level
of
the
modu-
lator
input required to
produce
3.2
MHz
at
the
modulator output.
Do
not
reset the vertical
POSITION
control of
CHANNEL
2 until this
adjustment
is
complete.
7.
Readjust
R126
for 4.6
MHz
as
indicated
on
the
scope.
A
correct
frequency of 4.6
MHz
is
indicated
when
there are
23
complete square
waves
in
ten divisions
when
the time-base
is
set
to 0.5 /isec/cm.
8.
Note
the position
(
dc voltage
level)
of the trace
on
CHANNEL
2 with reference to the trace
on
CHANNEL
1
(as
obtained
is
Step
7).
See
Fig.
5-2b.
Mark
the scope
graticule.
9.
Apply
a
stairstep signal
of
1.0 volt (p-p)
to the
TV
jack. See Fig. 5-la.
10.
Readjust
R126
(Carrier
Frequency) so that the
sync-tip part
of the
waveform
corresponds to the
position of the trace
measured
in
Step
6.
See
Fig. 5-2c.
11.
Adjust
R121
(Deviation Set) so that the
"top
step" peak-white part of the
signal
corresponds
to the position of the
trace
measured
in
Step
8.
See
Fig. 5-2c.
12.
Make
sure that a carrier
frequency of about
3.6
MHz
is
indicated
on
the
scope with no
signal
input.
Repeat Steps
5 to 11,
if
necessary.
Video
Level
is
now
set
to
produce the
maximum
devia-
tion
allowed
by
the system.
13.
Adjust
R335 (Video Output Level) to obtain
1.0volt(p-p)atTP-305.
14.
Proceed with Steps
11
to 13
in
Procedure
A
for
the
Dark and White
Clip Settings.
/::
TP-302
(3.2
MHz)
\
TP-105
Fig. 5-2a.
Waveforms
in
Steps
Sand
6
Fig. 5-2b.
Waveforms
in
Steps
7 and
8
modulator
input dc
level in
Step
8
/producing 4.6
MHz
modulator output
4.6
MHz
3.2
MHz
\
modulator
input
dc
level in
Step
6
producing 3.2
MHz
modulator output
Fig. 5-2c.
Maximum
deviation
setting
5-3