Check Delay Time Dial Range And Accuracy - Tektronix 2235A Instruction Manual

Adjustment Procedure
-
2235A lnstructlon
Use the Horizontal POSITION control to align the
first time marker that is 25 ns beyond the start of the
sweep with the second vertical graticule line.
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.
Repeat parts i and j for the remaining A SECIDIV and
time-mark generator setting combinations shown in
Table 5-6 under the XI0 Magnified column.
Set:
Horizontal MODE
A SEC/DIV
B SECIDIV
XI 0 Magnifier
B
0.1 ps
0.05 ps
Off (knob in)
Repeat parts b through k for the B Sweep. Keep the A
SECIDIV switch one setting slower than the B SEC/
DIV switch.
Check Delay Time Dial Range and Accuracy
Set:
Channel 1 Input Coupling GND
Horizontal MODE ALT
A and B SECIDIV 0.1 ms
XI 0 Magnifier
.
Off (knob in)
B DELAY TIME POSITION Fully counter-
clockwise
A TRIGGER Mode P-P AUTO
Align the start of the A Sweep with the 1 st vertical
graticule line using the Horizontal POSITION
control.
CHECK
-
lntensified portion of the trace starts within
0.5 division of the start of the sweep.
Rotate the B DELAY TlME POSITION control fully
clockwise.
CHECK- lntensified portion of the trace is past the
1 1 th vertical graticule line.
Set:
A and B SECIDIV
0.5 ps
B DELAY TIME POSITION
Fully counter-
clockwise
g. Align the start of the A Sweep with the 1st vertical
graticule line using the Horizontal POSITION
control.
h. CHECK- lntensified portion of the trace startswithin
1.1 divisions of the start of the sweep.
i.
Repeat parts d and e.
j. Set:
Channel 1 Input Coupling DC
Horizontal MODE B
A SECIDIV 0.5 ps
B SECIDIV 0.05 ps
B DELAY TIME POSITION 1.00
k. Select 0.5-ps time markers from the time-mark
generator.
I.
Adjust the Horizontal POSITION control so that the
top of the first fully displayed time marker is aligned
with the center vertical graticule line.
m. Without changing the Horizontal POSITION control
setting, set the B DELAY TlME POSITION dial to
9.00. Slightly readjust the B DELAY TlME POSITION
dial to align the top of the time marker with the center
vertical graticule line.
n. CHECK-The B DELAY TlME POSITION dial setting
is between 8.91 0 and 9.090.
0. Repeat parts I through n for the remaining A and B
SECIDIV and time-mark generator setting combi-
nations shown in Table 5-7.
p. Set:
A SECIDIV 5 PS
B SECIDIV
0.5 ps
B DELAY TIME POSITION 1.00
Table 5-7
Settings for Delay Time Accuracy Checks
Scans
by ARTEK MEDLQ =>
A SECIDIV
Switch
Setting
0.5
KS
5
LS
0.5 ms
5 ms
0.5 s
6 SECIDIV
Switch
Setting
0.05
US
0.5
LS
50
KS
0.5 ms
50 ms
Time-Mark
Generator
Setting
0.5
LS
5 us
0.5 ps
5 ms
0.5 s