Tektronix 323, Инструкция по эксплуатации

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Calibration— Type 323
13. Adjust Astigmatism O
a. Test equipment setup is shown in Fig. 6-6.
b. Set the INTENSITY control midway between a barely
visible trace and fully clockwise.
c. Connect the time-mark generator (Type 184) to the
VERT INPUT connector with the 42-inch BNC cable.
d. Set the time-mark generator for one-millisecond mark­
ers.
e. If necessary, set the TRIGGER control for a stable dis­
play.
f. CHECK—Markers should be well defined within the
areas indicated in Fig. 6-7A with optimum setting of focus
control.
g. ADJUST— FOCUS control and ASTIG adjustment, R597
(see Fig. 6-78), for the best definition of the markers within
the areas indicated in Fig. 6-7A.
14.
Adjust Trace Alignment
O
a. Position the baseline of the marker display to the cen­
ter horizontal line with the vertical POSITION control.
b. CHECK— Baseline of marker display should be parallel
to the center horizontal line.
c. ADJUST—TRACE ROTATION adjustment, R592 (see
Fig. 6-7B), so the baseline of the marker display is parallel
to the center horizontal line.
15. Adjust CRT Geometry
O
a. Set the VOLTS/DIV switch to .1.
b. Position the baseline of the marker display below the
bottom of the graticule with the vertical POSITION control.
c. CHECK— CRT display for curvature of vertical lines
(markers) within maximum deviation of 0.1 division from
straight line. Curvature can be most easily checked by posi­
tioning the markers to the vertical graticule lines with the
horizontal POSITION control. Fig. 6-7C shows a typical
display of good geometry.
d. ADJUST—Geom adjustment, R593 (see Fig. 6-7A), for
minimum curvature of vertical lines.
e. Disconnect the time-mark generator.
f. Position the trace to the top line of the graticule with
the vertical POSITION control.
g. CHECK— Deviation from straight line should not ex­
ceed 0.1 division.
h. Position the trace to the bottom line of the graticule
with the vertical POSITION control.
i. CHECK— Deviation from straight line should not ex­
ceed 0.1 division.
R69
VERT
X l
G A IN
'UUUU
Cornering
R593
Geom
R592
TRACE
ROTATION
RS97
ASTIG
A djust to r best d e fined markers w ith in
these areas.
Fig. 6 -7 . (A ) Typical CRT d isp la y w hen a d ju sting astigm atism ,
IB) location o f adjustm ents (m ain b o a rd ), (C) typ ica l CRT d ispla y
showing good geom etry.
NOTE
It may be necessary to compromise the setting of
the Geom adjustment to provide acceptable dis­
plays both in part c and parts g and i.
6-11