Tektronix 434, Instruction Manual, Page: 100 / 222

d. Set the T R IG G E R SOURCE to CH 1.
Calibration—434
e. C H E C K —C R T fo r a stable display.
f. A D J U S T —CH 1 Trigger DC Level adjustm ent R 284
(see Fig. 5-11) fo r a stable display.
30. Check Trigger C irc u it Operation
a. C onnect the signal fro m the signal generator to the
CH 1 in p u t connector via a GR to BNC adapter, a 42-inch
50 12 BIMC cable, and a BNC T connector. C onnect the
unused o u tp u t o f the BNC T c o n n e cto r to the E X T T R IG
in p u t co n n e cto r via a 42-inch 50 12 BNC cable and a 50 12
BNC te rm in a tio n .
b. C H E C K —Stable display can be obtained using the
signal a m p litu d e and coupling modes given in Table 5-5.
T A B L E 5-5
Trigger O peration Check
T R IG G E R
SOURCE
T R IG G E R
C O U P LIN G M in im u m Signal A m p litu d e
5 M Hz 25 MHz
CH 1
&
COMP
AC
DC
LF REJ
0.3 d iv
1 div
E X T
AC
DC
LF REJ
35 m V 125 m V
c. Set T R IG G E R SOURCE to COMP and T R IG G E R
C O U P LIN G to HF REJ.
d. A d ju s t the signal generator o u tp u t fo r a one-division
display o f th e 50 k ilo h e rtz reference frequency.
e. C H E C K —A stable display can be obtained.
f. A d ju s t the signal generator o u tp u t fo r a one-division
display o f a 1 megahertz signal.
g. C H E C K —A stable display can n o t be obtained.
h. Replace the M edium -Frequency C o n sta n t-A m p litu d e
Signal Generator w ith a Low -F requency Signal Generator
and remove the 50 12 BNC te rm in a tio n fro m the test setup
(42-inch 50 12 BNC cable should be connected d ire c tly to
the E X T TR IG in p u t connector).
i. Set the T R IG G E R C O U PLIN G to LF REJ.
j. A d ju s t the Low -F requency Signal Generator fo r a
one-division display o f a 30 k ilo h e rtz signal.
k. C H E C K —A stable display can be obtained.
I. A d ju s t the signal generator fo r a one-division display
o f a 100 hertz signal.
m . C H E C K —A stable display can n o t be obtained.
n. A d ju s t the signal generator fo r a one-division display
o f a 100 k ilo h e rtz signal.
o. Set Sweep M O DE to N O R M .
p. C H E C K —Should be able to ob ta in a stable display.
When the T R IG G E R L E V E L co n tro l is rotated fu lly
co u nterclockw ise or clockw ise, there should be no display
presented on the C RT.
31. Check Single Sweep O peration
a. A d ju s t the signal generator fo r a 0 .3-division display
o f a 1 k ilo h e rtz signal.
b. Set the T R IG G E R C O U P LIN G to AC.
c. A d ju s t the T R IG G E R L E V E L co n tro l fo r a stable
display.
d. Set the Sweep M ODE to S IN G LE SWEEP.
e. Press the RESET b u tto n .
f. C H E C K —A single-sweep display (one sweep only) is
presented.
g. Rotate the T R IG G E R L E V E L c o n tro l fu lly c lo c k ­
wise.
5-22