Operating
Instructions—
7B53A/7B53AN Operators
Delayed
Sweep
Triggering
A
LEVEL
control and SLOPE, COUPLING, and
SOURCE switches
are provided
for
delayed sweep trig
gering. When
the
LEVEL control is rotated to the RUNS
AFTER
DLY TIME position
the delayed sweep starts
immediately
after
the delay time. The DLY'D TRIG
LEVEL control and
the
SLOPE, COUPLING, and SOURCE
switches are inoperative.
This mode
permits the selection of
continuously variable delay
times (by varying
the DELAY
TIME MULT
dial).
DLY'D
TRIG
IN.
This connector is an external input for
the
delayed triggering circuit when the DLY'D TRIG
SOURCE
switch
is set to EXT. When the DLY'D TRIG
SOURCE switch
is
set to INT and P613 is properly
connected
(see Fig.
1-3), the DLY'D TRIG IN connector
serves
as
a Delayed Sweep Gate Out connector (not
labeled). The Delayed
Sweep Gate signal is a rectangular
positive-going pulse
with approximately 3.0 volts
amplitude
and
pulse
width coincident with the delayed sweep.
When
the DLY'D TRIG
LEVEL control is
rotated
counterclockwise (out of switch detent),
the delayed sweep
is
triggerable. The delayed sweep does not
start at the
completion
of the delay time but, waits until a trigger pulse
is
received by the
delayed sweep triggering
circuit. The
delay
time in this mode is dependent not
only on the
settings
of the delay-time
controls, but
on the
delayed
sweep triggering
controls and the occurrence of the delayed
sweep triggering signal. The primary purpose of this mode is
to
eliminate jitter from
the display delayed sweep wave
form.
Since the delayed sweep is triggered by the input
waveform,
jitter is eliminated from the delayed sweep
display even
though
it may
be
inherent in the input
waveform.
When the
delayed sweep is triggerable, the LEVEL
control
can be rotated to
select the amplitude point on the
trigger signal
at
which
the delayed sweep is triggered. The
DLY'D
TRIG
SLOPE, COUPLING, and SOURCE switches
are
activated and their functions are the
same for delayed
triggering
as
functions with the same title are for MAIN
TRIGGERING
(see Main Triggering Level, Slope, Coupling,
and
Source discussions in this section).
Input/Output
Connectors
Two dual-function
BNC connectors
are provided on the
instrument
front-panel.
MAIN
TRIG IN OR AMP IN.
This
connector is
an
external
trigger input for the main
triggering circuit when
the
MAIN TRIGGERING SOURCE switch is set to EXT or
EXT ÷
10
and the TIME/DIV OR
DLY TIME switch is set
to
any
position except AMPL. When
the TIME/DIV OR
DLY
TIME
switch
is set to AMPL and the MAIN
TRIGGERING
SOURCE switch
is set to EXT or EXT ÷ 10,
this
connector serves
as an external
horizontal input (see
X-Y
Operation).
X-Y
Operation
Some
applications require one
signal displayed versus
another
rather
than against time (internal sweep). The
amplifier function
of the 7B53A/7B53AN allows an
external
signal
to be applied to the horizontal deflection
system either externally via
the MAIN TRIG
IN OR AMP
IN
connector or
internally by way of the triggering system.
To
apply
an external signal (X-signal) to the horizontal
system,
set the 7B53A/7B53AN TIME/DIV OR DLY TIME
switch
to AMPL
and the MAIN TRIGGERING SOURCE
switch
to EXT. The MAIN TRIGGERING
COUPLING
selected
affects the frequency response of
the X-signal.
Apply
the external signal to the MAIN TRIG IN OR AMP
IN
connector. Deflection factor of the
X-signal is provided
in multiples of 10
as shown in Table
1-1. The Y-signal
can
be
applied to
the plug-in unit installed in the vertical
compartment.
TABLE 1-1
MAIN
TRIGGERING
COUPLING
MAG
DEFLECTION
FACTOR
(within
10%)
EXT
X
10
10
mV/div
EXT
X1
100 mV/div
EXT:
10
X
1
1
V/div
To
apply
the
X-signal internally via the triggering system
set
the TIME/DIV
OR DLY TIME switch to AMPL and the
MAIN
TRIGGERING SOURCE switch
to INT. Apply the
external
signal
to the Amplifier unit installed in the vertical
compartment. The
attenuator
switch of the Amplifier unit
determines the horizontal deflection factor.
For
information
on X-Y applications see the oscilloscope
manual. Also, the reference books listed under Applications
provide
information on X-Y measurements
and
interpreting
the resultant lissajous displays.
1-14
