B&K 1076, Instruction Manual, Page: 37 / 64

smce
it
is
180"
from
reference
signal.
Fig.
HI
will
be
extremely
useful
in
servicing
color
TV
receivers
since
it
will
enable
you
to
evaluate
performance
of
the
receiver.
It
will
also
enable
you
to
check
the
range
of
the
hue
control
and
will
provide
a
simple
method
of
color
demodulator
alignment.
Since
most
of
the
color
TV
receivers
in
use
today
demodulate
an
+
(R-Y)
and
'a
+
(B-Y)
signal,
our
discussion
of
demodulator
alignment
will
refer
to
this
condition
only.
Connect
the
Television
Analyst
to
the
receiver
under
test
and
set
up
and
adjust
for
a
proper
picture
on
the
TV
receiver.
Be
sure
that
the
horizontal
frequency
of
the
Analyst
is
adjusted,
to
the
correct
frequency.
This
is
ex­
plained
in
your
instmction
manual.
Tum
the
color
signal
on
and
insert
the
color
bar
slide
into
the
Analyst.
Adjust
video
control
on
the
Analyst
to
get
Figure
19-Color
bar
pattern
showing
each
bar,
its
number
and
its
color
good
reproduction
of
the
bars
and
adjust
chroma
and
hue
controls
for
the
proper
level
of
the
color
signal
and
that
the
color
bars
occur
in
the
proper
sequence
as
shown
in
Fig.
19.
If
the
color
bars
do
not
fall
into
the
proper
sequence,
the
coarse
adjustment
of
the
hue
range
found
inside
the
receiver
will
center
the
range
of
the
hue
control.
At
this
point
it
is
well
to
indicate
that
the
horizontal
width
of
the-
receiver
under
test
should
be
reduced
to
be
certain
that
all
ten
bars
are
seen.
From
fundamental
color
theory
we
know
that
the
output
of
the
+
(R-Y)
demodulator
if
properly
adjusted
should
have
zero
+
(B-
Y)
output,
and
the
output
of
the
+
(B-Y)
demodulator
should
have
zero
output
of
+
(R-Y)
signal.
Since
our
i:olor
bar
pattern
has
both
an
+
(R-
Y)
signal
which
is
the
third
bar,
and
a
+(B-Y)
signal
which
is
the
sixth
bar,
we
can
use
these
signals
to
check
and
align
color
demodulators.
Connect
an
oscilloscope
of
adequate
band
width
to
the
output
of
the
+
(R-
Y)
demodulator.
. You
will
see
a
waveform
similar
to
that
shown
in
Fig.
20.
This
is
viewed
at
a
15,750
cycle
per
second
sweep
on
the
oscilloscope.
The
sixth
bar
which
is
+
(B-
Y)
should
be
at
zero
amplitude
as
shown
in
Fig.
20.
If
this
condition
is
not
met,
set
the
hue
control
to
its
center
position
and
ad­
just
the
coarse
hue
control
adjusment
which
is
located
within
the
TV
re­
ceiver
so
that
the
sixth
bar
is
at
zero
amplitude.
Now
move
the
oscilloscope
to
the
output
of
the
+
(B-Y)
demodulator
and
adjust
the
quadrature
trans­
former
driving
the
+
(B-
Y)
demodulator
· so
that
the
third
bar
which
is
+
(R-
Y)
is
at
zero
amplitude
as
shown
in
Fig.
21.
35