d. Center the IF CENTER FREQ controls and change the
DISPERSION to 50 kHz/div.
e. Apply 10 ns and 10 s markers from the Time-Mark
Generatar to the RF INPUT.
f. Check-the range of the IF CENTER FREQ-FINE control.
Must equal or exceed 50 kHz either side af center.
g. Center the IF CENTER FREQ controls, change the DIS-
PERSION bock to 500 kHz/div and apply 10 ns and 1 s
markers,
h. Check-the dispersion accuracy (Fig. 6-31) at each DIS-
Measure dispersion accuracy within the center 8 div of the
display for each selector position and over the + and 2.5
MHz range of the IF center frequency. Check the accuracy
with the IF CENTER FREQ control centered, then rotate the
control to the dial reading noted in step c for 2.5 MHz from
center, and check the dispersion accuracy.
Decrease the sweep speed as the dispersion is decreased,
and increase resolution by uncoupling the RESOLUTION
selector. Turn the control counterclockwise to optimize mark-
er definition. Switch the VERTICAL DISPLAY selector to LOG
and the VIDEO FILTER on at these slower sweep rates and
narrow dispersion settings.
i. T u r n t h e V I D E O F I L T E R t o O F F a n d t h e V E R T I C A L
DISPLAY selector to LIN.
DISPERSION
Divisions per
kHz/DIV
Marker Selector
marker
10 ns and 1 s
2
500
10 ns and 5 s
1
200
10 ns and 10 s
100
1
10 ns and 10 S
50
2
10 ns and 50 s
1
20
10 ns and .1 ms
1
10
10 ns and .1 ms
5
10 ns and .5 ms
2
1
10 ns and .5 ms
Fig. 6-31. Typical displays when checking or
adjusting kHz/DIV