4.Final Display Adjustments (SN 3001A and Below)

Reference

4. Final Display Adjustments (SN 3001A and Below)

AlAl Keyboard

AlA Z Axis Amplifier

AlA X Deflection Amplifier

AlA Y Deflection Amplifier

Description

Note

Procedure

Note

This procedure is used to optimize the appearance of the CRT display during routine maintenance or after CRT replacement or minor repairs. First, the display is adjusted for best focus over the full CRT, then the graticule pattern is adjusted for optimum rectangular display.

Adjustment Procedure 2, High Voltage Adjustment (SN 3001A and Below) should be performed prior to performing the following adjustment procedure.

1.With the spectrum analyzer LINE switch set to STANDBY, set the potentiometers listed in lhble 3-5 as indicated. See Figure 3-30 for the location of the adjustments.

In this procedure, do not adjust the following potentiometers and precision variable capacitors on the AlA Z-Axis Amplifier, AlA X-Axis Amplifier, or AlA Y-Axis Amplifier Assemblies: AlA2R36 INT LIMIT, AlA2R22 HF GAIN, AlABClO, AlA4R28 HF GAIN, AlA4C10, AlA4Cl1, AlA5R28 HF GAIN, AlA5C10, or AlA5Cll. These components are adjusted in Adjustment Procedure 2, High Voltage Adjustments (SN 3001A and Below) and Adjustment Procedure 3, Preliminary Display Adjustments (SN 3001A and Below).

‘Ihble 3-5. Initial Adjustment Positions

Adjustment

Position

Front-panel INTENSITY

fully clockwise

Front-panel

FOCUS

centered

Front-panel

ALIGN

centered

AlA2R5 INT GAIN

fully clockwise

2.Set the LINE switch to ON and wait at least 5 minutes to allow the CRT and high-voltage circuits to warm up. The spectrum analyzer power-up annotation should be visible on the CRT display.

3.For an initial coarse focus adjustment, adjust AlA3R15 FOCUS LIMIT, AlA2R36 ASTIG, and AlA2R30 FOCUS GAIN in sequence for best displayed results.

4.Adjust AlA4R7 X POSN, AlA4R27 X GAIN, AlA5R7 Y POSN, and AlA5R27 Y GAIN for optimum centering of the display annotation and graticule pattern.

Adjustments 3-59