Final Display Adjustments (Sn 3001A And Below) - HP 8568B Performance Tests And Adjustments Manual

4. Final Display
Adjustments (SN
Reference
Description
Note
Procedure
Note

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

This procedure is used to optimize the appearance of the CRT display
during routine maintenance or after CRT replacement or minor
the
repairs. First, 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
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,
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).
Adjustment
Front-panel INTENSITY fully clockwise
Front-panel FOCUS
Front-panel ALIGN
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
and graticule pattern.
the
following potentiometers and
Position
centered
centered
fully clockwise
Adjustments 3-59