
Performance Check/Calibration—Type 324
c. CHECK—Stable CRT display can be obtained with
the TRIGGER control set to + and — AUTO and in the
va ria b le p o s itiv e - and negative-slope areas (adjust
TRIGGER control as necessary).
d. Without changing the output amplitude, set the
low-frequency generator to 30 hertz.
e. Set the TIM E/D IV switch to 10 ms.
f.
CHECK—Stable CRT display cannot be obtained at
any setting of the TRIGGER control (notice that dis
plays presented in the AUTO positions do not remain
stable).
44. Check Trigger Slope Operation
a. Change the following control settings:
TRIGGER
+ AUTO
Trig/Horiz Coupling
INT TRIG AC
TIM E/DIV
.5 ms
b. Set the low-frequency generator for a four-division
display at one kilohertz.
c. CHECK—CRT display starts on the positive slope
of the waveform (see Fig. 5-14A).
d. Turn the TRIGGER control clockwise until a
stable display is obtained in the positive-slope area.
e. CHECK—CRT display starts on the positive slope
of the waveform.
f. Turn the TRIGGER control clockwise until a
stable display is obtained in the negative-slope area.
g. CHECK—CRT display starts on the negative slope
of the waveform (see Fig. 5-14B).
h. Set the TRIGGER control to —AUTO.
i.
CHECK—CRT display starts on the negative slope
of the waveform.
Fig. 5-14. (A) Typical CRT display when checking positive-slope
triggering, (B) Typical CRT display when checking negative-slope
triggering.
45. Check Trigger Control Range
a. Remove the 50-ohm termination and reconnect the
low-frequency sine-wave generator to the BNC T con
nector through the 42-inch BNC cable.
b. Change the following control settings:
VOLTS/DIV
.5
TRIGGER
+AUTO
Trig/Horiz Coupling
EXT TRIG AC
c. Set the low-frequency generator fo r a 3.2-division
display (1.6 volts peak to peak) at one kilohertz.
d. CHECK—Rotate the TRIGGER control throughout
the positive-slope area and check that the display can be
triggered (stable display) at any point along the positive
slope of the waveform (indicates TRIGGER control
range of at least + and — 0.8 volts). Display is not trig
gered at either extreme of the positive-slope area except
in +AUTO detent.
e.
CHECK—Rotate the TRIGGER control throughout
the negative-slope area and check that the display can
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