Variable Time/Division Range - Tektronix 7B92A Maintenance Manual

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.
5-3; at least 2-1/2 Delaying sweep markers to one
Delayed sweep marker are visible.
Fig. 5-3. Variable Time/Division range.
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.
B6 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).
b. Set the time-mark generator for 100 ms
markers.
Performance Check/Calibration-7B92A
c. Set the vertical amplifier plug-in unit deflection
factor for approximately two divisions of display.
d. Set the DELAY TIME MULT dial to 0.90.
e. Align the time-mark to the center vertical
graticule line, using the POSITION control.
f. Turn the
approximately 8.9 to align the time-mark to the center
vertical graticule line.
g. Check-the DELAY TIME MULT dial to read
within three minor divisions of 8.90 (8.87 to 8.93).
h. Repeat parts d through g of this step for each
sweep rate given in Table 5-5. Maintain approximately
two divisions of display.
DIFFERENTIAL DELAY TIME ACCURACY
TIME/DIV OR
DLY TIME
.
2 s
.1 s
50 ms
20 ms
10 ms
5 ms
2 ms
1 ms
.5 ms
.2 ms
.1 ms
50 µs
20 µs
10 µs
5 µs
2 µs
1 µs
.5 µs
.2 µs
.1 µs
5-13
DELAY TIME MULT
Table 5-5.
Time-mark
DLY'D Generator
Time/Division Setting
5 ms 0.1 s
2 ms 50 ms
I ms 10 ms
0.5 ms 10 ms
0.2 ms 5 ms
0.1 ms 1 ms
50 µs
1 ms
20 µs
0.5 ms
10 µs
0.1 ms
5 µs
0.1 ms
2 µs
50µs
1 µs 10 µs
.5 µs 10 µs
.2 µs 5 µs
.1 µs 1 µs
1 µs
50 ns
0.5 µs
20 ns
0.1 µs
10 ns
5 ns 50 ns
5 ns 50 ns
dial to