Tektronix 221, Инструкция по эксплуатации

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Calibration—221 Service
e. Increase the frequency of the constant amplitude
signal generator to 500 kHz w ith o u t changing the signal
amplitude.
f. Check for a display greater than 4.2 divisions.
g. Set the HORIZ-MAG switch 10X and repeat steps d
through f.
26. Check/Adjust Sweep Cal (Timing)
a. Set the HORIZ MAG to IX .
b. Set the INPUT COUPLING to DC.
c. Connect the probe to the output of the time mark
generator (TG 501) using a probe tip to BNC adapter and a
50-ohm termination.
d. Set the SEC/DIV switch to 2 m.
e. Set the time mark generator (TG 501) for 2 m illi­
second time marks.
f. Check that the time marks align w ith the graticule
lines over the center eight divisions.
j. Set the time mark generator for 1 /is time marks.
k. Check that the time marks align w ith the graticule
(disregard the first 0.5 /is o f the display).
I. Adjust C354 so that the time marks align w ith the
center eight graticule lines. See Fig. 5-9.
m. Set HORIZ MAG to 10X.
n. Set time mark generator for 1 /is time marks.
o. Check that the time marks align w ith the center eight
divisions of the graticule w ithin 5% (disregard first .5 /is of
sweep)
27. Check Horizontal Position Range
a. Set the HORIZ MAG switch to 10X.
b. Check that the right and left ends of trace can be
positioned to center of screen.
c. Disconnect all test equipment.
g. Adjust the SWP CAL adjustment R354 so that the
time marks align with the center eight graticule lines. See
Fig. 5-9.
h. Check all other ranges o f tim ing w ithin 3%. Use
appropriate settings on the time mark generator.
i. Set the SEC/DIV to 1 /is.
Fig. 5-9. Location of Sweep Cal and Auto Preset adjustments.
REV. B, FEB. 1977
5-13