Initial Control Settings

PROCEDURE STEPS

POWER

AUTO INTENSITY AUTO FOCUS

Vertical

Channel 1 POSITION VERTICAL MODE CH 1 VOLTS/DIV CH 1 VOLTS/DIV Variable INVERT

Channel 1 AC-GND-DC Channel 2 AC-GND-DC

Horizontal

POSITION

HORIZONTALMODE SEC/DIV SEC/DIV Variable X10 Magnifier MULTIPLIER

Trigger

VAR HOLDOFF

TRIGGER MODE

SLOPE

LEVEL

SOURCE EXT COUPLING

ON (button in)

As desired

Best focused display

Midrange CH 1 0.5 V

CAL detent Normal (button out) DC GND

Midrange NO DLY 0.1 ms CAL detent Off (knob in) <X1

NORM AUTO

Midrange VERT MODE EXT DC-MO

1. Adjust Horizontal Amplifier Gain (R752 and R733)

a. Connect 0.1-ms time markers from the time-mark generator via a 50-ii cable and a 50-i2 termination to the CH 1 OR X input connector. Connect the generator Trigger output via a 50-i2 cable and a 50-J2 termination to the EXT INPUT connector.

b. ADJUST-Horiz Gain (R752) for 1 time marker per division.

c. Set the X10 Magnifier on (knob out) and select 10-j/s time markers from the time-mark generator.

d. ADJUST—X10 Gain (R733) for 1 time marker per division.

2. Adjust Magnifier Registration (R758)

a. Select 0.5-ms time markers from the time-mark generator and set the X10 Magnifier off (knob in).

b. Position the middle time marker to the center vertical graticule line using the Horizontal POSITION control.

c. Set the X10 Magnifier on (knob out).

d. ADJUST-Mag Registration (R758) to position the middle time marker on the center vertical graticule line.

e. Set the X10 Magnifier off (knob in).

f. CHECK-There is no discernable shift in the time marker when switching between X10 Magnifier on and X10 Magnifier off.

g. Turn the X10 Magnifier on (knob out) and repeat parts b through e until no further improvement is noted.

3. Adjust 5-jus Timing (C626)

a. Set the SEC/DIV switch to 5 ms.

b. Select 5-jus time markers from the time-mark generator.

c. ADJUST—5 ¡is Timing (C626) for 1 time marker per division across the graticule area.

4. Adjust High-Speed Timing (C754, C774, C784, and C734)

a. Set the SEC/DIV switch to 0.05 jus.

b. Select 50-ns time markers from the time-mark generator.

c. ADJUST—50 ns Linearity (C754) for equally spaced time markers at the start of the sweep.

d. Set the X10 Magnifier on (knob out) and select 10-ns time markers from the time-mark generator.

NOTE

In the next part, keep the adjustment screws for

C774 and C784 as close to the same length as possible.

e. ADJUST—5 ns Timing (C774 and C784) alternately for one time marker every 2 divisions over the center 8 divisions of the magnified sweep.

f. Adjust the Horizontal POSITION control so that the 5th time marker is aligned with the 2nd vertical graticule line.

g. ADJUST—5 ns Linearity (C734) for one time marker every 2 divisions over the center 8 divisions of the magnified sweep. Adjust the Horizontal POSITION control to check the linearity to the 15th time marker.

h. Repeat parts e through g until no further improvement is noted.

i. Set the X10 Magnifier off (knob in) and recenterthe trace using the Horizontal POSITION control.

j. Repeat parts b through i until no further improvement is noted.

5. Check Timing Accuracy a. Select 50-ns time markers from the time-mark generator.

b. Use the Channel 1 POSITION control to center the trace vertically. Adjust the TRIGGER LEVEL control for a stable, triggered display.

c. Use the Horizontal POSITION control to align the first time marker that is 50 ns beyond the start of the sweep with the 2nd vertical graticule line.

NOTE

When making timing measurements, use as a reference the same point on each time marker.

d. CHECK-Timing accuracy is within the limits shown in Table 5-6 for the applicable position of the X10 Magnifier. When making the check with the X10 Magnifier On, exclude any portion of the sweep past the 100th magnified division.

Table 5-6 Timing Accuracy

X10 Magnifier

Accuracy at 10th Vertical Graticule Line

Off (knob in)

3% (0.24 division)

On (knob out)

5% (0.40 division)

e. Repeat parts b through d for the SEC/DIV and timemark generator setting combinations shown in Table 5-7 under the "Normal" column.

Table 5-7

Settings for Timing Accuracy Checks f. Set:

SEC/DIV X10 Magnifier

Table 5-7

Settings for Timing Accuracy Checks

SEC/DIV

Time-Mark Generator Output

owitcn

Setting

Normal

X10 Magnified

0.05 jus

50 ns

10 ns

0.1 jus

0.1 ms

10 ns

0.2 ms

0.2 ms

20 ns

0.5 ms

0.5 ms

50 ns

1 ms

1 ms

0.1 ms

2 ms

2 ms

0.2 ms

5 ms

5 ms

0.5 ms

10ms

10ms

1 ms

20 ms

20 ms

2 ms

50 ms

50 ms

5 ms

0.1 ms

0.1 ms

10 ms

0.2 ms

0.2 ms

20 ms

0.5 ms

0.5 ms

50 ms

1 ms

1 ms

0.1 ms

2 ms

2 ms

0.2 ms

5 ms

5 ms

0.5 ms

10 ms

10 ms

1 ms

20 ms

20 ms

2 ms

50 ms

50 ms

5 ms

0.1 s

0.1 s

10 ms

0.2 s

0.2 s

20 ms

0.5 s

0.5 s

50 ms

g. Select generator.

10-ns time markers from the time-mark h. Repeat parts b through d for the SEC/DIV and timemark generator setting combinations shown in Table 5-7 under the "X10 Magnified" column.

6. Check SEC/DIV Variable Range a. Set:

CH 1 VOLTS/DIV SEC/DIV SEC/DIV Variable X10 Magnifier

Fully counterclockwise Off (knob in)

b. Select 0.5-ms time markers from the time-mark generator.

c. CHECK—Time markers are 1 division or less apart.

d. Return the SEC/DIV Variable control to the CAL detent.

7. Check Delay Time Range a. Set:

Channel 1 AC-GND-DC GND HORIZONTALMODE INTENS

b. CHECK-Each DELAY TIME and SEC/DIV combination under "MULTIPLIER <X1" in Table 5-8 produces a nonintensified display of length shown in the "Display Length" column.

Table 5-8 Delay Time Range Checks

MULTIPLIER <X1

MULTIPLIER >X20

DELAY TIME Setting

SEC/DIV Setting

Display Length (Divisions)

SEC/DIV Setting

Display Length (Divisions)

0.5 ms

0.1 ms

<5

2 ms

>5

10 ms

2 ms

<5

50 ms

>4

0.2 ms

50 ms

<4

1 ms

>4

c. Rotate the MULTIPLIER control to >X20.

d. CHECK-Each DELAY TIME and SEC/DIV combination under "MULTIPLIER >X20" in Table 5-8 produces a nonintensified display of length shown in the "Display Length" column.

8. Check Delay Time Jitter a. Set:

CH 1 VOLTS/DIV 0.5 V

Channel 1 AC-GND-DC DC

SEC/DIV 50 ms

DELAY TIME 10ms

MULTIPLIER <X1

b. Select 50-/is time markers from the time-mark generator.

c. Align the 1st time marker with the 1st graticule line. Adjust the MULTIPLIER control so that the intensified sweep starts on the 5th time marker to produce a 200-jus delay.

d. Set the SEC/DIV switch to 0.05 lis and set the HORIZONTAL MODE switch to DLY'D. Adjust the MULTIPLIER control slightly to bring the leading edge of the time marker within the graticule area, if it is not already visible.

e. CHECK-Jitter on the leading edge of the time marker does not exceed 0.8 division. Disregard slow drift.

e. CHECK—Start of the sweep can be positioned to the right of the center vertical graticule line by rotating the Horizontal POSITION control fully clockwise.

f. Disconnect the test setup.

CH 1 VOLTS/DIV 20 mV

SEC/DIV X-Y

b. Connect a 0.1-V standard-amplitude signal to the CH 1 OR X input connector using a 50-f2 cable.

c. ADJUST-X Gain (R709) for exactly 5 divisions of horizontal deflection.

d. Disconnect the test setup.

9. Check POSITION Control Range a. Set:

SEC/DIV 10 MS

HORIZONTALMODE NO DLY

b. Align the 3rd time marker with the center vertical graticule line.

c. Set the X10 Magnifier knob to On (knob out).

d. CHECK-Magnified time marker can be positioned to the left of the center vertical graticule line by rotating the Horizontal POSITION control fully counterclockwise.

11. Check X-Bandwidth a. Connect a 50-kHz leveled sine-wave signal via a 50-i2 cable and a 50-ii termination to the CH 1 OR X input connector.

b. Set the generator to obtain a 5-division horizontal display.

c. Adjust the generator output frequency to 2 MHz.

d. CHECK-Display is at least 3.5 divisions in length.

e. Disconnect the test setup.

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