Tektronix 2221 - Page 144

Appendix A - 2221 Operators
Table A - 5
Settings for Timing Accuracy Checks
b . Use the Channel 1 POSITION control to center the
base line vertically and the Horizontal POSITION control to
align the start of the trace with the 1st vertical graticule
line ,
Time -
Mark
Generator
Setting
SEC / DIV
Switch
Setting
u
Normal ( X1 )
X10
Magnified
C. Use the CURSORS control and SELECT C1 / C2
switch to set one cursor exactly on the 2nd vertical grati
cule line and position the active cursor to the right using
the CURSORS control until AT readout displays 0.800 ms .
50
ns
0.05
us
0.1
us
0.2
us
0.5
us
0.1
us
0.2
us
0.5
us
10
ns
10
ns
20
ns
50
ns
1
us
2
us
d .
CHECK
-
Graticule
indication of cursor
difference at
the
10th vertical
graticule
line is
within
0.16
division .
1
us
2
us
5
us
0.1
us
0.2
us
0.5
us
5
us
e . Set the
Channel 1 AC - GND
- DC switch to
DC .
10
us
20
us
50
US
10
us
20
us
50
US
1
us
2
us
5
us
U
f . Select 1
ms time
markers from
the time
- mark
generator .
0.1
ms
0.2
ms
0.5
ms
0.1
ms
0.2
ms
0.5
ms
10
uS
20
us
50
us
U
비
g . Align the
2nd time
marker with
the 2nd
vertical grati
cule line using
the
Horizontal
POSITION
control .
1
ms
1
ms
2
ms
5
ms
2
ms
5
ms
0.1
ms
0.2
ms
0.5
ms
1
ms
h . Set the SAVE / CONT switch to SAVE for a stable
display .
10
ms
20
ms
50
ms
10
ms
20
ms
50
ms
ul
2
ms
5
ms
0.1
s
0.2
s
0.5
s
0.1
s
0.2
s
0.5
s
10
ms
20
ms
50
ms
i . Use the CURSORS control and SELECT C1 / C2
switch to set the first cursor on the trailing edge of the
2nd time
marker
.
1
j . Press in the C1 / C2 button to activate the second
cursor .
j . CHECK - Timing accuracy is within 3 % ( 0.24 division
at the 10th vertical graticule line ) , and linearity is within 5 %
( 0.1 division over any 2 of the center 8 divisions ) . Exclude
any portion of the sweep past the 100th magnified
division ,
|
k . Set the second cursor on the trailing edge of the
10th time marker at the same voltage level as on the 2nd
time
marker
.
k . Repeat parts i and į for the remaining SEC / DIV and
time - mark
generator setting
combinations
combinations shown in
Table
A - 5
under the “ X10
Magnified
"
column
.
1. CHECK_The AT readout is between 0.798 ms and
0.802
ms
.
2. Check Store Differential and Cursor Time
Difference
Accuracy
m . Set the SAVE / CONT switch to CONT .
|
a
.
Set :
n . Set the SEC / DIV switch to 0.5 us .
Channel
1
AC - GND - DC
SEC
/
DIV
X10
Magnifier
STORE
/
NON -
STORE
GND
0.1
ms
Off (
knob
in )
STORE (
button in )
0. Select 0.5 us time markers from the time - mark
generator
.
บ
A - 12
U