Tektronix 7D20 Operator's Manual page 45

Step 4
Adjust the VERT CTR (vertical center) and VERT GAIN (vertical gain)
controls to align the upper and lower horizontal edges with horizontal
lines 1 and 7 of the display graticule as shown in Figure 2-9 (bottom
graticule line is 0) . As with the HORIZ CTR and HORIZ GAIN controls,
these vertical adjustments are interactive and may require that you work
back and forth between them to optimize this adjustment .
Figure 2-9 . Adjust VERT CTR and VERT GAIN .
Step 5
Adjust the VECT LIN (Vector Linearity) control to close the crossing pattern
in the DISPLAY CAL test pattern as shown in Figure 2-10 . This will
optimize the vector display by compensating for the delay line length of
the host mainframe .
Figure 2- 1 0 . Adjust VECT LIN .
Operating Instructions-7D20
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