Section -4; Applications - Tektronix 545A Instruction Manual

The Type 545A
Oscilloscope
is
an
extremely versatile
instrument
which
is
adaptable
to
a
great
number
of appli-
cations.
However,
to
make
use of the
full
potentialities
of
the instrument,
it is
necessary that
you
understand
com-
pletely
the
operation
of
each
control. This portion of the
instruction
Manual
is
intended
to
provide
you
with the basic
information
that
you require.
If
you are familar with other
Tektronix Oscilloscopes,
you should
have
very
little
diffi-
culty
in
understanding the operation
of
the
Type
545A
since the function of
many
controls
is
the
same
as the func-
tion
of corresponding controls
on
other
Tektronix
instru-
ments.
Plug-In Units
The Type
545A
Oscilloscope
is
designed
to
operate with
any one
of
the Tektronix
letter-series
plug-in
units.
The
particular plug-in unit
used must be
selected
by you
to
satisfy
the
requirements
of
your application.
In
selecting
the plug-in unit for
any
particular
application,
you must
consider
the
bandpass,
sensitivity,
and
the
type
of input
required
for that
application.
The
plug-in
units
available
will satisfy
the requirements
for
most
applications.
Fig.
2-1. Inserting the selected plug-in unit into
the oscilloscope
plug-in
unit
compartment.
SECTION
2
OPERATING
INSTRUCTIONS
Preparation
for
use
When
the
plug-in unit
has
been
selected,
insert
it
into
the plug-in
compartment
of
the oscilloscope
and
press
firmly to insure that the connectors
make
proper
contact
(see Figure 2-1).
Tighten the
plug-in unit locking control to
hold the
unit
securely
in
place
and
turn
the oscilloscope
INTENSITY
control
fully
counterclockwise.
Connect
the
power
cord
to
the rear of the instrument
and
to the
power
line
and
place the
POWER
switch
in
the
ON
position.
Time Delay
Time
delay relays used
in
Type 545A
Oscilloscopes delay
operation
of the instrument
for
approximately 25 seconds
after the
POWER
switch
is
turned on
to
allow a
brief
tube-
warmup
period.
The delay allows
the tubes
sufficient
time
to
heat before
the
dc operating voltages are applied.
If
the ac
power
is
off for only
an
instant,
the
normal 25-
second delay
will
occur before the
instrument returns to
full
operation.
This
delay
will
occur regardless of
whether
the ac
power
is
off
because
of a
momentary power
failure
or
is
turned
off
with the
POWER
switch.
Focus
and
Astigmatism Contois
The
FOCUS
and
ASTIGMATISM
controls
operate
in
con-
junction with
each
other
to
allow you
to obtain a sharp,
clearly
defined spot or
trace.
The
proper
setting of
the
ASTIGMATISM
control
is
obtained by
rotating the
FOCUS
control fully
clockwise,
setting
the
HORIZONTAL
DISPLAY
switch
to
EXT. XI
0,
and
adjusting the
INTENSITY
control
to
obtain a spot
on
the screen. After positioning the spot to
the center of the screen, the
ASTIGMATISM
control
is
ad-
justed for
the
most
nearly circular spot possible.
The
FOCUS
control
is
then adjusted
to
reduce the spot diameter as
much
as possible.
(You must be certain that
all
input signals
to
the oscilloscope
are disconnected
when
you
adjust the
FOCUS
and
ASTIGMATISM
controls.)
Intensity
Control
The
INTENSITY
control
is
used
to
adjust the brightness
of the oscilloscope display. This
permits you
to
compensate
for
changes
in
brightness resulting
from
changes
in
the
sweep
or triggering
rate.
The
INTENSITY
control
is
rotated
clockwise to increase
brightness
and counterclockwise
to
decrease brightness.
Care must be taken
when
using the
INTENSITY
control
that the brightness
is
not turned
up
to
®I
2-1