Tektronix DD 501 Instruction Manual page 30

Performance Check/Calibration
—
DD
501
b.
Connect
a 120
millivolt,
65 megahertz
signal
from
sine-wave generator through a
BNC
T
connector
to
START
INPUT
connector.
c.
Connect
BNC
probe
tip
adapter through 50
ohm
termination
to
open end
of
BNC
T
connector.
d.
Connect 10X probe from one
vertical
channel
of test
oscilloscope
to
BNC
probe
tip
adpater.
Connect 10X
probe from
other
channel
of test
oscilloscope
to
START
TRIG VIEW
probe connector.
e.
Set
test
oscilloscope to
display several cycles of
both
input signals.
f.
CHECK—
ThatSTARTTRIG'D
light
Ison
and remains
on
as
START LEVEL
control
is
rotated
from
fully
clockwise
to
counterclockwise positions.
Push
RESET
button
and check
that
START
TRIG'D
indicator ex-
tinguishes.
g.
Set
START LEVEL
control to display
a triggered
signal
on
test
oscilloscope
crt.
h.
CHECK—
That
START
TRIG'D
indicator
is
on and
the
two
displayed
sine-wave
signals are of
equal frequen-
cy.
i.
Move
BNC
T
connector
and
associated connections
to
EVENTS INPUT
connector.
Move
1
0X
probe
to
EVENTS
TRIG VIEW
probe connector.
j.
CHECK—
That
EVENTS
TRIG'D
light
is
on when
EVENTS
LEVEL
control
is
set for triggered display
at
maximum
amplitude on
crt.
k.
Disconnect
all
signal
connections from
DD
501.
8.
Check
Frequency Response and Output
Amplitudes
a.
Connect a 120
millivolt,
40 megahertz
signal
from
sine-wave generator through a 50
ohm
termination
and
dual input coupler to
START
and
EVENTS INPUTS
connectors.
b.
Set
EVENTS DELAY
COUNT
switch
to
00000.
c.
Connect DLY'D
TRIG
OUT
connector through 50
ohm
termination
to test
oscilloscope
vertical input.
d.
CHECK—
That
all
TRIG'D
indicators are
on
to
indicate
proper
triggering
when EVENTS
and
START
LEVEL
controls are set for
a triggered display
on
test
oscilloscope.
(DLY'DTRIG
OUT
signal
frequency should
be
half of
EVERNTS INPUT
frequency
at
40 megahertz.)
e.
CHECK—
That amplitude
of
DLY'D TRIG
OUT
display
on
crt
is
at least
1
volt.
9.
Check Minimum
Input Pulse
Width Triggering
a.
Connect
a
200
millivolt,
100 megahertz
signal
from
sine-wave generator through
a
50
ohm
termination
and
dual input
coupler
to
EVENTS
and
START
INPUT connec-
tors.
b.
CHECK—
That
EVENTS
TRIG'D,
START
TRIG'D,
and DLY'D
TRIG
indicators
can be
lit
simultaneously
by
setting
START
and
EVENTS LEVEL
controls.
c.
Disconnect
all
signal
connections from
DD
501.
10.
Check Throughput Time and Recycle Rate
a.
Connect equipment
as
shown
in
Fig. 5-1.
b.
Set
square-wave generator
for 0.5 volt,
500
kilohertz
output signal.
c.
Set
START
and
EVENTS LEVEL
controls
to
produce
a delayed
trigger
output
which matches
input
frequency
(monitored
on
test
oscilloscope
crt).
d.
Center both displays
on
crt
and
set
sweep
rate to 5
nanoseconds/division.
e.
CHECK—
Time
difference
between two
pulses
(at
50%
level)
for less than
30 nanoseconds. Refer
to
Fig. 5-2.
f.
Disconnect cable from pulse generator
and connect
to
sine-wave generator.
g.
Set sine-wave generator
for a
1
volt,
20 megahertz
output
signal.
h.
CHECK—
That
input-to-output
frequency
ratio
can
be
set to 1:1
using
START
and
EVENTS
LEVEL
controls.
REV
C,
FEB
1979
5-7