Philips PM 3266 - 3.4.9. Sensitivities

154
—
Set
the
m.t.b.
TIME/DIV
switch
to
.1 ms
and
its vernier
to CAL
—
Set
the
d.t.b.
TIME/DIV
switch
to
.05
fis
and
its vernier
to
CAL
—
Set the
DELAY
TIME
control
(R1)
to
1.00
-
Apply
a time
marker
voltage
with
a
repetition
rate
of
.1 ms
to the
channel
A input
-
Check
that
the
intensified
spot on
the
trace
coincides
with
the
starting
point of
the
second
time
marker
pulse;
if
necessary,
readjust
potentiometer
R1384
on
the
trigger
amplifier
board
—
Set the
DELAY
TIME
control
(R1
)
to
9.00
-
Check
that
the
intensified
spot
on
the
trace
coincides
with
the
starting
point of
the
tenth
time
marker
pulse;
if
necessary,
readjust
potentiometer
R1379
on the
trigger
amplifier
board
—
Remove
the
input
signal.
As both
adjustments
are
slightly
interdependent,
they
must
be
repeated
until
both
conditions
are
fulfilled.
3.4.8A.
Alternate
time-base
and
trace
separation
-
Depress
push-button
A
of
the
display-mode
controls
(SI
)
-
Depress
push-button
ALT
TB of
the
X deflection
controls
(S2)
—
Set the
m.t.b.
TIME/DIV
switch
to
.5
ps and
its vernier
to
CAL
—
Set
the
d.t.b.
TIME/DIV
switch
to
.5
p%
and its vernier
to
CAL
—
Depress
push-button
0 of
the
channel
A
signal-coupling
controls
-
Check
that
the
distance
between
the
two traces
is
0 DIV
with the
TRACE
SEP
control
turned
anti-clockwise
and
approximately
4
DIV
with
this
control
turned
clockwise.
3.4.9.
Sensitivities
Before
checking
the
sensitivities,
check
the
balances
in
accordance
with
section
3.4.7.
Balance
adjustments.
3.4.9.1.
Gain
(sensitivity)
Y/\
VIA
X
—
Depress
push-button
B
of
the
display-mode
controls
(SI
)
-
Depress
push-button
EXT
X DEFL of
the
X
deflection
controls
(S2)
—
Push the
Y
POSITION
controls
to position
NORMAL
—
Depress
push-button
AC of the
channel
A signal-coupling
controls
—
Depress
push-button
A of the
m.t.b.
trigger-source
controls
(S22)
—
Set the
d.t.b. TIME/DIV switch
to
OFF
—
Set the channel
A
AMPL switch
to .5 V/DIV and
its
vernier
to CAL
—
Apply a 3 V
square-wave voltage,
frequency
2
kHz,
to the channel
A input.
—
Check
that the
trace
width is 6
DIV; if necessary,
readjust
GAIN potentiometer
R12
on the front
panel.
3.4.9.2.
Gain
(sensitivity)
Ya
VIA Y
(unit
13)
—
Depress
push-button
A of the display-mode
controls
(SI
)
—
Depress
push-button
MAIN TB of
the
X
deflection
controls
(S2)
—
Push
the Y
POSITION controls
to position NORMAL
—
Depress
push-button
AC of the channel
A
signal-coupling
controls
—
Depress push-button A
of
the
m.t.b. trigger-source
controls
(S22)
—
Set
the
d.t.b. TIME/DIV switch
to
OFF
—
Set
the channel
A
AMPL
switch
to
.5 V/DIV
and
its
vernier to
CAL
—
Apply
a 3 V square-wave
voltage,
frequency 2 kHz, to the channel A input.
—
Check that the
trace-height is
6 DIV; if
necessary, readjust potentiometer
R654
on the final Y
amplifier
board
—
Check that
the
control range of the
channel
A
vernier
control is 1
:2,6
to 1
;3,5
and
that the pilot
lamp
UNCAL lights
up
as
soon
as the vernier is
out
of the
CAL position
3. 4. 9.3.
Gain (sensitivity)
Yq VIA Y
—
Depress
push-button
B
of the display-mode
controls (SI
)
—
Depress push-button
MAIN TB of the
X
deflection
controls
(S2)
—
Push
the
Y POSITION
controls
to position NORMAL
—
Depress
push-button
AC
of the
channel
B
signal-coupling
controls
—
Depress
push-button
B of
the
m.t.b.
trigger-course
controls
—
Set the
d.t.b. TIME/DIV switch
to
OFF
—
Set the channel
B AMPL switch
to .5 V/DIV and its vernier
to CAL