Magnifier Registration; Magnifier R E G Istratio N; A And B Timing Accuracy And Linearity; A And B Magnified Timing Accuracy - Tektronix 2246 1Y Service Manual

4. Magnifier Registration

a. Set X I 0 MAG on.
b. Position the rising edge of a time marker to the
center vertical graticule line.
c. Set X I 0 MAG off.
d. CHECK—for less than 0.5 division horizontal
trace shift.

5. A and B Timing Accuracy and Linearity

a. Set A SEC/DIV to 20 ns.
b. Set tim e-m ark generator for 20 ns time marks.
c. Position the time marker peaks vertically to the
center horizontal graticule line (allows use of the
minor division graticule markings as an aid in
making the accuracy checks).
d. Position the second time marker to the second
vertical graticule line.
e. CHECK—that the tenth marker is within ± 0 .1 6
division of the tenth graticule line.
f. CHECK—that in any group of three time mark­
ers, having the first and third markers aligned
with their respective graticule lines, the second
marker is within ± 0.05 division of its graticule
line.
g. Repeat the procedure for all other SEC/DIV set­
tings. Use Table 4-3,
Accuracy Checks, for the SEC/DIV and tim e -
mark generator settings.
h. Set SEC/DIV to 20 ns.
i. Set tim e-m ark generator for 20 ns time marks.
j. Set:
Horizontal MODE
B INTEN
k. Repeat the CHECK procedure for all the B SEC/
DIV settings.
Performance Check Procedure—2246 1Y and 2246 Mod A Service
Settings for Timing
B
For a viewable
display

6. A and B Magnified Timing Accuracy

a. Set tim e-m ark generator for 5 ns time marks.
b. Set:
Horizontal MODE
A SEC/DIV
Horizontal MODE
Horizontal POSITION
X I 0 MAG
CH 1 VOLTS/DIV
c. Align the rising edge a time marker with the
second vertical graticule line (center the display
vertically).
d. CHECK—that the rising edge of the fourth dis­
played time marker to the right of the one posi­
tioned in step c. crosses the center horizontal
graticule line at between 8.27 divisions to 8.73
divisions.
e. Set SEC/DIV to 5 ns.
f. Align a time marker to the second vertical
graticule line.
g. CHECK—that the tenth displayed time marker is
within 0.24 division (left or right) of the tenth
graticule line.
h. Repeat the timing checks for all SEC/DIV set­
tings between 10 ns and 0.5 s. Use the SEC/DIV
and Time Mark Generator X I 0 MAG settings
given in Table 4-3.
A
20 ns
B
12 o 'clock
On (for
2 ns/div sweep
speed)
0.5 V (use
0.2 V for the
5 ns time
markers if
necessary)
4-19