Variable Time/Division Range - Tektronix 7B92A Maintenance Manual

C14. Check Variable Time/Division Range
a. Remove the 7B92A from the oscilloscope plug-
in compartment.
b. Place the Time/Division Variable Selector
multi-pin connector on P761 (Delaying Sweep). See Fig.
1-1 for location.
c. Insert the 7B92A into the oscilloscope plug-in
compartment; turn on the power to the oscilloscope.
d. Set the time-mark generator for 100 pµ
markers.
e. Set the TIME/DIV OR DLY TIME and DLY'D
Time/Division switch
Time/Division knob out for Alternate mode. Check that
the DELAY TIME MULT dial is 0.0.
f. Press and release VARIABLE control and turn
it fully counterclockwise.
g. Check-that Delaying sweep markers (top) and
Delayed sweep markers are displayed as shown in Fig.
5-8; at least 2-1/2 Delaying sweep markers to one
Delayed sweep marker are visible.
h. Remove the 7B92A from the oscilloscope plug-
in compartment; reposition the Time/Division Variable
Selector multi-pin connector to P760 and re-install the
7B92A into the plug-in compartment. Turn on power to
the oscilloscope.
i. Check-with VARIABLE control released and
turned fully counterclockwise, at least two Delayed
sweep markers (bottom) to one Delaying sweep marker
is visible. Refer to Fig. 5-14.
C15. Check Differential Delay Time Accuracy
a. Set the TIME/DIV OR DLY TIME switch to 200
ms, DLY'D Time/Division switch (pull knob out) to 5 ms
(then push knob in), push in VARIABLE (CAL IN) control,
and adjust MAIN TRIGGERING LEVEL control for a
stable display (TRIG'D light on).
20 µs
to and pull DLY'D
Fig. 5-14. Variable Time/Division Range
b.
markers.
c.
factor for approximately two divisions of display.
d.
e.
graticule line, using the POSITION control.
f.
approximately 8.9 to align the time-mark to the center
vertical graticule line.
g.
within three minor divisions of 8.90 (8.87 to 8.93).
h.
sweep rate given in Table 5-10. Maintain approximately
two divisions of display.
5-38
Performance Check/Calibration-7B92A
Set the time-mark generator for 100 ms
Set the vertical amplifier plug-in unit deflection
Set the DELAY TIME MULT dial to 0.90.
Align the time-mark to the center vertical
Turn the DELAY TIME
Check-the DELAY TIME MULT dial to read
Repeat parts d through g of this step for each
MULT dial to