Tektronix 371B, Service Manual

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Performance Verification
5-34
371B Service Manual
9. CHECK that the three intermediate vertical dots conform to the center
vertical graticule line within 0.5 minor division.
If the dots do not conform, the following adjustment is necessary.
Adjusting Orthogonality.
10. ADJUST ORTHOGONALITY adjustment R80 on the A5 Display Control
board so that the three intermediate vertical dots conform to the center
vertical graticule line.
Examining NonĆStore Gain.
11. EXAMINE the display to determine if the outer eight dots of the test pattern
are positioned within the inner and outer frame patterns.
If the positioning is not correct, the following adjustment is necessary.
Adjusting XĆGain and YĆGain.
12. ADJUST X-GAIN adjustment R554 and Y-GAIN adjustment R574 on the
A5 Display Control board to position the outer eight dots of the dot pattern
within the inner and outer frame patterns.
Checking and Adjusting Geometry.
13. Change the following 371B settings:
14. CHECK the frame test pattern for
v
0.5 minor division of bowing and
v
0.75 minor division of keystone effect.
If the bowing and keystone effect are not within these limits, the following
adjustment may be necessary.
15. ADJUST GEOMETRY adjustment R410 on the A18 CRT Output board (if
necessary) for minimum display bowing.