TM 9-6625-1753-14
C3
Table 2-4. Oscilloscope Check Procedures-Continued
Table 2-4. Oscilloscope Check Procedures-Continued
Step
Operation
Normal Indication
Corrective procedure
Step
Operation
Normal Indication
Corrective procedure
Refer to the dual trace plug-in func-
5. Check Triggered Delayed Sweep.
a. Adjust the DELAY VERNIER control (37) until the strobe (brightened portion) covers the leading edge of the
d.
Set the channel B NORM-INVERT switch (49 or 71) to INVERT (or INVERT AC).
waveform.
b. Set the DISPLAY LOGIC switch to TRIG-DLY'D.
A 4-division square wave is present.
Refer to the dual trace plug-i n func-
The portion of the waveform previously covered by the strobe is not on the screen,
horizontally expanded or magnified 5 times (10 divisions).
e.
Set the MODE switch to A (or CH1), and the NORM-INVERT switch to NORM (or NORM AC).
Refer to the delaying sweep plug-in
Check delayed sweep circuit of the de-
3.
Check the X10 Probes.
a. Connect one X10 probe to the channel A 1 MEG connector (54) and the other X10 probe to the channel B 1 MEG
laying sweep plug-in.
connector (47)(or CH1 1 MEG 14PF and CH2 1 MEG 14PF, 74 and 69, respectively).
Note. It may be necessary to slightly adjust the DELAY VERNIER control to see the leading edge of the
b. Set the channel A and channel B VOLTS/DIV switches to .02 (or 0.2 and PULL X10).
waveform.
c. Connect the channel A probe tip to the CAL IV connector (4 1).
A 5-division peak-to-peak square wave is present.
6.
Check Delay Vernier Control.
Center the waveform on the CRT with
a. Set the DELAYED SWEEP-PULL TO UNLOCK switch (26) to 0.2 mSEC (for 400-Hz source); 1 mSEC for 60-Hz
the channel A POSITION control (5 or
source.
56) if necessary.
b. Set the DELAY VERNIER control to 0 (on both the window and knob skirt).
Rotate the body of the probe if the
c. Set the DISPLAY LOGIC switch to TRIG-STROBE.
square wave is distorted (overshoot or
d. Set the DELAY VERNIER control to 4 (window)(on the skirt).
undershoot).
The 2-division waveform portion between the 4th and 6th divisions is brighter than the
Perform the probe set-up procedure
remainder of the presentation.
Refer to the delaying sweep plug-in
Refer to par. 2-7.
d. Set the MODE switch to B (or CH2).
Check delay pick-off circuit of the de-
e. Repeat step c for the channel B probe.
laying sweep plug-in.
Center the waveform on the CRT with
7.
Check Armed-Strobe Sweep.
the Channel B POSITION control (44
a. Set the DELAYED SWEEP-PULL TO UNLOCK switch to 5 mSEC.
or 65) if necessary.
b. Set the DISPLAY LOGIC switch to ARM-STROBE.
f. Set the MODE switch to A (or CH1).
The strobe (brightened segment) appears on the leading edge of the waveform. The
g. Set the channel A and channel B VOLTS/DIV switches to CAL.
SWP READY indicator lamp (35) flickers.
Refer to the delaying sweep plug-in
4.
Check Triggered-Strobe Sweep.
Check delayed sweep circuit of the de-
a.
Pull the DELAYED SWEEP-PULL TO UNLOCK switch (26), and rotate it until the white scribe mark is alined with
laying sweep plug-in.
the .5 mSEC position. (The cutout of the TIME/DIV switch plastic skirt should still be at the initial setting.)
8.
Check Armed-Delayed Sweep.
b. Set the DISPLAY LOGIC switch to TRIG-STROBE.
a. Set the DISPLAY LOGIC switch to ARM-DLY'D.
A small portion of the square-wave signal is brighter than the rest of the waveform.
The strobe portion (leading edge of the waveform) is now present, horizontally
Adjust the DELAY VERNIER control
expanded or magnified 5 times. The SWP READY indicator lamp continues to flicker.
(37).
Refer to the delaying sweep plug-in
Refer to the delaying sweep plug-in
Check delayed sweep circuit of the de-
Check delayed sweep circuit of the de-
laying sweep plug-in.
laying sweep plug-in.
b. Set the channel A VOLTS/DIV switch to .02 (or .2 and PULL X10).
c. Set both SOURCE switches (21 and 29) to INT.
d. Rotate the LEVEL control (36) to eithe r extreme.
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