Tektronix 221, Инструкция по эксплуатации

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Calibration—221 Service
13. Check/Adjust Attenuation Compensation
a. Set the VO LTS/D IV switch to .2 and, set the
SEC/DIV switch to .1 m. See Fig. 5-6 for location of atten­
uator adjustments.
b. Adjust the output of the square-wave generator fo r a
display o f 4 divisions in amplitude.
c. Check fo r a square wave that is fla t (flat top).
d. Adjust C l22 fo r a square wave that is fla t (flat top).
e. Set the square-wave generator fo r 50 kHz.
f. Set the SEC/DIV switch to 10 jus.
g. Check fo r a square wave that is flat.
h. Adjust C120 fo r a square wave that is flat.
i. Set the V O LTS/D IV switch to 2.
j. Set the SEC/DIV switch to .1 m.
k. Set the square-wave generator to 5 kHz and adjust
the output fo r a four-division display.
l
. Check display fo r a fla t square wave.
m. Adjust C l25 fo r a flat square wave.
n. Set the square-wave generator fo r a 50-kHz signal.
o. Set the SEC/DIV switch to 10 jus.
p. Check the display for a flat square wave.
q. Adjust C l23 fo r a fla t square wave.
r. Set the VO LTS/D IV switch to 20 and remove the
50 ohm term ination.
s. Set the o utput of the square-wave generator fo r a
five kHz, four-division signal.
t. Set the SEC/DIV switch to .1 m.
Vert Gain
C126 C123 R417
1 5 7 3 -1 6
Fig. 5-6. Location of attenuator compensation and Vertical Gain
adjustments.
u. Check fo r a fla t square wave.
v. Adjust C l28 fo r a fla t square wave.
w. Set the square-wave generator fo r a 50-kHz signal.
x. Set
t h e
SEC/DIV
s w itc h t o
10
/Us.
y. Check fo r a fla t square wave.
z. Adjust C126 fo r a square wave that is flat.
14. Check/Adjust Vertical Gain
a. Set the V O LT S /D IV switch to 50 m.
b. Set the SEC/DIV switch to .2 m.
c. Set INPUT COUPLING to DC.
d. Connect the standard amplitude calibrator to the 221
oscilloscope. Use a probe tip to BNC adapter.
e. Set the standard amplitude calibrator fo r a 0.2 volt
signal.
f Check fo r a display o f four divisions.
g. Adjust R417 fo r a display o f fo ur divisions w ithin
2%. See Fig. 5-6.
h. Check all the VO LTS/D IV switch settings (see
Table 5-2).
Table 5-2
V O L T S /D IV
Standard Amplitude Number of
Setting
Calibration Setting Divisions
5 m
20 m Volts
4
10 m
50 m Volts 5
20 m
.1 V o lt 5
50 m
.2 V o lt 4
.1
.5 V o lt 5
.2
1 V o lt 5
.5
2 Volts 4
1
5 Volts 5
2
10 Volts 5
5
20 Volts 4
10
50 Volts 5
20
100 Volts
5
50
100 Volts
2
100
100 Volts
1
5-8
REV. D, SEPT. 1977