Tektronix 2236, Instruction Manual

Page: 119 / 350

Adjustment Procedure— 2236 Service
d. Set:
HORIZONTAL MODE B
A SEC/DIV 0.2
ms
B SEC/DIV 0.1
ms
e. ADJUST— B High Speed Tinning (C713) for 1 time
marker per division over the center 8 divisions.
8. Adjust 5-ns Timing and Linearity (C775 and
C785)
a. Set:
CH 1 VOLTS/DIV
Horizontal POSITION
HORIZONTAL MODE
A SEC/DIV
X I0 Magnifier
0.2 V
Midrange
A
0.05
ms
On (knob out)
d. Use the Horizontal POSITION control to align the sec­
ond time marker with the second vertical graticule line.
e. CHECK—Timing accuracy is within 2% (0.16 division
at the 10th vertical graticule line), and linearity is within 5%
(0.1 division over any 2 of the center 8 divisions).
NOTE
For checking the timing accuracy of the A SEC/DIV
switch settings from 50 ms to 0.5 s, watch the time
marker tips only at the 2nd and 10th vertical graticule
lines while adjusting the Horizontal POSITION control.
f. Repeat parts c through e for the remaining A SEC/DIV
and time-mark generator setting combinations shown in Ta­
ble 5-5 under the “Normal” column.
b. Select 10-ns time markers from the time-mark
generator.
c. Align the time markers with the vertical graticule lines
using the Horizontal POSITION control.
d. ADJUST—5-ns Timing (C775 and C785 alternately)
for one time marker every 2 divisions over the center 8 divi­
sions of the magnified sweep.
e. CHECK— Time markers between the 2nd and 4th ver­
tical graticule lines should be aligned within 0.05 division. If
not, a slight compromise between timing and linearity
should be made by readjusting the 5-ns Timing capacitors
(C775 and C785).
9. Check Timing Accuracy and Linearity
a. Set:
CH 1 VOLTS/DIV 0.5 V
X I0 Magnifier Off (knob in)
A TRIGGER Mode NORM
b. Select 50-ns time markers from the time-marker
generator.
c. Adjust the A TRIGGER LEVEL control for a stable,
triggered display.
Table 5-5
Settings for Timing Accuracy Checks
SEC/DIV Time-Mark Generator Setting
Switch Setting
Normal X I0 Magnified
0 .0 5
m s
5 0 ns 10 ns
0.1
ms
0.1
ms
10 ns
0 .2
m
s 0 .2
ms
2 0 ns
0 .5
m
s
0 .5
fis 50 ns
1 MS
1
m s
0.1 MS
2 MS
2 MS 0 .2
ns
5
MS
5 MS
0.5
m s
10 MS 10 MS
1
m s
2 0 MS 2 0
ms
2 MS
5 0
m
S
5 0
m s
5
m s
0.1 ms 0.1 ms 10 MS
0 .2 ms 0 .2 ms
2 0
ms
0 .5 ms 0 .5 ms
5 0
m s
1 ms
1 ms 0.1 ms
2 ms 2 ms 0 .2 ms
5 ms 5 ms 0 .5 ms
10 ms 10 ms 1 ms
2 0 ms
2 0 ms
2 ms
5 0 ms 5 0 ms
5 ms
A Sweep Only
0.1 s 0.1 s
10 ms
0.2 s 0.2 s 20 ms
0.5 s 0.5 s 50 ms
5-17