Tektronix 7B92A Maintenance Manual page 59

m. Check-for a stable display with no more than
0.05 division of jitter.
n. Check-change Delayed Triggering SOURCE to
INT and repeat m of this step.
A7. Check HF Sync Triggering
a. Disconnect the 50-n cable from the DLY'D
TRIG IN connector and reconnect it to the MAIN TRIG IN
connector.
b. Set the Delayed Triggering LEVEL control to
RUNS AFTER DELAY TIME.
c. Set the DLY'D Time/Division switch to Normal
mode (knob in).
d. Set the MAIN TRIGGERING MODE to HF
SYNC.
e. Set the vertical amplifier
volts/division switch to 1 V.
f. Set the MAIN TRIGGERING LEVEL control for
a stable display (TRIG'D light on).
g. Check-for a stable display with no more than
0.05 division of jitter.
h. Set the high-frequency leveled sine-wave
generator for a one-division display.
i. Check-change
SOURCE to EXT 10 and repeat part g of this step.
j. Disconnect the 50-Ò cable from the high-
frequency leveled sine-wave generator.
A8. Check Line Triggering
a. Disconnect the 50-Ò cable from the MAIN TRIG
IN connector.
b. Set the MAIN TRIGGERING MODE to AUTO,
SOURCE to LINE, and COUPLING to AC; the TIME/DIV
OR DLY TIME switch to 1 ms; and DLY'D Time/Division
to 1 ms (knob in).
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plug-in unit
the MAIN TRIGGERING
Performance Check/Calibration-7B92A
c. Check-set the MAIN TRIGGERING LEVEL
control near "0" and check that the TRIG'D light is on.
d. Check-that the display is not triggered (TRIG'D
light off) at either end of the MAIN TRIGGERING LEVEL
control rotation.
A9. Check Single Sweep Operation
a. Connect the time-mark generator to the input of
the vertical amplifier plug-in unit, using a 50-n cable; set
the generator for 1 ms markers.
b. Set the vertical amplifier plug-in unit deflection
factor for approximately two divisions of display; and
adjust MAIN TRIGGERING LEVEL control for a stable
display.
c. Set the MAIN TRIGGERING SOURCE to INT,
MODE to SINGLE SWEEP, and SOURCE to EXT.
d. Press the SINGLE SWEEP RESET pushbutton;
it should be lit.
e. Check-change the MAIN TRIGGERING
SOURCE to INT and observe that only one sweep is
displayed and SINGLE SWEEP RESET pushbutton goes
out.
f. Set the TIME/DIV OR DLY TIME switch to
Alternate mode (PULL FOR ALT).
g. Set the MAIN TRIGGERING SOURCE to EXT;
press the SINGLE SWEEP RESET pushbutton.
pushbutton should be lit.
h. Check-change the MAIN TRIGGERING
SOURCE to INT and observe that only one sweep is
displayed and SINGLE SWEEP RESET pushbutton goes
out.
i. Press SINGLE SWEEP RESET pushbutton
several times and observe that display alternates
between Delaying and Delayed sweeps.
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