Adjust B Trigger Centering And; Adjust A Trigger Centering And; Adjust Trigger Dc Balance - Tektronix 475 Instruction Manual

c. CHECK— That a stable display can just be obtained by
rotating the B LEVEL control.
d. Adjust the Medium-Frequency signal generator to
increase the CRT display to 0.35 division.
e. A DJU ST—B Trigger Sensitivity adjustment, R785 {see
Fig. 5-20) so that a stable display can just be obtained by
rotating the B L EV E L control.
40. Adjust B Trigger Centering and Symmetry
a. Set both T IM E /D IV switches to 1 0
controls to 0, the CH 1 V O L T S /D IV switch to 50 m V , and
the B SOURCE switch to NORM.
b. Adjust the Medium-Frequency signal generator for a 2
division display of a 350 kilohertz signal.
c. Vertically center the display about the center hori­
zontal graticule line.
d. CHECK—CRT display begins at the same vertical
point in both slopes of the displayed waveform.
e. A DJUST—B Trigger Symmetry adjustment, R767 (see
Fig. 5-20), so that the trace begins at the same point in
both slopes of the displayed waveform.
f. A DJUST—B Trigger Centering adjustment, R754 (see
Fig. 5-20), for the trigger point of the display to be at the
graticule center.
g. CAL A ID —A gap equal
between the + and — trigger points.
41. Adjust A Trigger Centering and Symmetry
a. Set the H O R IZ D ISPLA Y switch to A and the A
SOURCE switch to NORM.
b. C H E C K -C R T display begins at the same vertical
point in both slopes of the displayed waveform.
c. AD J U S T -A Trigger Symmetry adjustment, R547 (see
Fig. 5-20), so that the trace begins at the same point in
both slopes of the displayed waveform.
®
, both LEVEL
ms
to 35 m V should exist
d. A DJU ST—A Trigger Centering adjustment, R534 (see
Fig. 5-20), for the trigger point of the display to be at the
graticule center.
e. CAL A ID —A gap equal
between the + and — trigger points.

42. Adjust Trigger DC Balance

a. Set the A COUPLING switch to DC, the A SOURCE
switch to NORM, and the A L EV E L control to 0.
b. Adjust the Medium-Frequency signal generator for a
0.3 division display.
c. Position the display to the vertical center of the
graticule viewing area.
d. CHECK— That a stable display can be obtained on
both slopes of the displayed waveform.
e. A DJUST—Normal Trigger DC Balance adjustment,
R425 (see Fig. 5-21), so that the display begins at the same
DC level when switching the A COUPLING switch from DC
to AC.
f. Set the A SOURCE switch to CH 1.
g. CHECK— That a stable display can be obtained on
both slopes of the displayed waveform.
h. A DJU ST— C H I
R403 (see Fig. 5-21), so that the display begins at the same
DC level when switching the A COUPLING switch from DC
to AC.
Fig. 5-21. Location of Normal Trigger DC Balance and CH 1 Trigger
DC Balance adjustments.
Calibration—475
to 35 m V should exist
Trigger DC Balance adjustment,
5 4 1