
2. High-Voltage Adjustment (SN
and Below)
If the calibration factor calculated in step 8 is 0.00099, and
is labeled for -3875 V, then adjust
HV ADJ for
a DVM indication of:
0.00099 x (-3875 V) = -3.836 V dc
16. With the front-panel INTENSITY control fully counterclockwise,
wait approximately 30 minutes to allow the high-voltage supply to
stabilize and the CRT to normalize. This
turn-on will extend
CRT life expectancy, particularly if a new CRT
has
just been
installed.
17. Readjust
HV ADJ for a DVM indication equal to the
voltage determined in step 15.
18. If a new CRT has just been installed do the following:
a. Set the front-panel INTENSITY control so the CRT trace is
barely visible.
b. Wait an additional 30 minutes for the CRT to normalize.
c. Readjust
HV ADJ for a DVM indication equal to the
voltage determined in step 15.
Focus and Intensity
19. Set the LINE switch to STANDBY. Remove the ac line cord from
Adjustments
each instrument section.
20. Wait at least one minute for
the
MAINS power-on indicator
(red LED) to go out completely before proceeding.
21. Disconnect the high-voltage probe from
22. Remove the
Intensity Control Assembly from the IF-Display
Section and install in its place the Display Adjustment Board,
HP part number 85662-60088. Set the switch on
the
Display
Adjustment Board in the “down” position. (This applies
approximately
V dc to the front-panel INTENSITY control.)
23. Connect a calibrated
divider probe to the oscilloscope
Channel 1 input.
24. On the oscilloscope, press (RECALL) (CLEAR) to perform a soft reset.
On the oscilloscope, press
more preset probe , select
channel 1, and use the front-panel knob to select a
probe.
26. Set the oscilloscope controls as follows:
Press
Channel 1 . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . on
amplitude scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Press
time scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Press
EDGE TRIGGER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . auto, edge
source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
level . . . . . . . . . . . . . . . . . . . . . . . . .
V, rising edge
Press
connect dots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Adjustments 3-33
Summary of Contents for 8568B
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