HP 8560A, Service Manual

Page: 53 / 450

2. Display Adjustment
Fast Zero Span Adjustments
22. Set SWEEP OFFSET, VIDEO OFFSET, VIDEO GAIN and
SWEEP GAIN to midrange. Adjustment locations are shown in Figure 2-4 for
these A2 adjustments.
23. Set the HP 355D Attenuator to provide 30 attenuation.
24. Press on the analyzer, and connect the equipment as shown in Figure 2-2. Set
the HP 8560A controls as follows:
C E N T E R F R E Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...300 MHz
SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 Hz
REF LVL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
RES BW
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VIDEO BW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sweep time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 ms
25. Press
MARKER-> REF LVL .
If the marker is not at the top graticule, press
MARKER-B REF LVL
again.
Press
(SAVE), SAVE STATE,
and
STATE 0.
27. Set sweeptime to 10 ms.
28.
Press
(SAVE), SAVE STATE,
and
STATE 1 .
29. Adjust SWEEP OFFSET to place the beginning of the trace at the leftmost
vertical graticule line.
30. Adjust SWEEP GAIN to place the end of the trace at the tenth vertical graticule
line (one division from the right edge of the graticule).
31. Press and press the (up) key seven times.
Press SAVE STATE
, and
STATE 2.
Set the sweep time to
50 ms. Press SAVE STATE,
and
STATE 3 .
Press RECALL STATE,
and
STATE 1 .
Switch between
STATE1
and
STATE2.
Adjusting and so that in STATE1
the trace is lined up with the top graticule and in STATE2 the trace is lined up with the
eighth graticule (from the top line). Repeat until they align to within
divisions.
36. Adjust and until the start of sweep is aligned to the leftmost vertical
graticule line and the stop sweep is aligned with the right most vertical graticule line.
37. Press STATE2
and
STATE3.
The two traces should be aligned /-.l divisions.
Press STATE0
and
STATE1
. The two traces should be aligned /-.l divisions.
Adjustment Procedures 2-19