TB 9-6625-2240-24
Table 14. High Frequency Compensation Adjustments
Oscilloscope calibrator
Test instrument
EDGE settings
Aberration limits
TIME/DIV
CH1
minor division or
Portion of
switch
AMPLITUDE
adjustments
minor division
settings
(R)
pk-pk
affected
(s)
(<)
200 mVpp
1 MHz
0.1
1
C175, R175 (fig. 1)
10 ns from
0.05
leading edge
C133, R133 (fig. 1)
2 ns from
leading edges
C112, R112 (fig. 1)
Front corner
.5 s
200 mVpp
100 kHz
1
Top and corner
R109 (fig. 1)2
1
200 mVpp
10 kHz
20
Top and corner
10
R139 (fig. 1)
R475 (fig. 2)3,1
5
R494 (fig. 2)1
1
1Affect
both CH1 and CH2. Readjust as necessary.
2Test instrument with SN B250000 and above.
3Optional on some test instruments.
(6) Remove TI connection from CH1 and connect to CH2 and press VERT MODE
CH2 pushbutton (in).
(7) Set TI VOLTS/DIV CH2 switch to 5m (10m for Tektronix, Type 475A).
(8) Use technique of step 9 below for TI settings and oscilloscope calibrator output
listed in table 15.
(9) Rotate oscilloscope calibrator knob below EDIT FIELD pushbutton to adjust
amplitude for 5 divisions of vertical deflection on TI. Square wave will have aberrations not
Table 15. High Frequency Compensation Adjustments
Oscilloscope calibrator
EDGE
Test instrument
settings
Aberration limits
TIME/DIV
CH2
minor division or
Portion of
switch
AMPLITUDE
adjustments
minor division
settings (s)
(R)
pk-pk
affected
(<)
200 mVpp
1 MHz
0.1
1
C275, R275 (fig. 1)
10 ns from
0.05
leading edge
C233, R233 (fig. 1)
2 ns from
leading edges
C212, R212 (fig. 1
Front corner
200 mVpp
100 kHz
0.5
1
Top and corner
R209 (fig. 1)2
200 mVpp
10 kHz
20
1
Top and corner
10
R239 (fig. 1)
R475 (fig. 2)3,1
5
R494 (fig. 2)1
1
1Affect
both CH1 and CH2. Readjust as necessary.
2Test
instrument with SN B250000 and above.
3Optional on some test instruments.
15