Tektronix 442, Инструкция по эксплуатации

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Calibration Procedure—442 Service
Adjustment Procedure
3. Vertical Output Amplifier and Vertical
Preamplifier Gain
NOTE
The vertical system gain should not require readjust­
ment unless the crt or other vertical components
have been replaced or adjustments have accidental­
ly been altered.
a. Set:
VOLTS/DIV (CH 1 & CH 2) 2 m (IX)
AC-GND-DC (CH 1 & CH 2) DC
VERT MODE CH 1
SEC/DIV .2 m
TRIGGERING MODE AUTO
SOURCE CH 1/CH 2
CPLG AC
LEVEL Fully cw
b. Connect a 50 Q cable from the high-amplitude
output of the square-wave generator, through a 10X
attenuator and a 50 O termination, to the CH 1 input
connector. Set the generator to 1 kHz and set the
generator amplitude to provide a 5-division display.
c. ADJUST—C4114 (see Figure 4-9) for best square
front corner (see Figure 4-10 for example).
d. Set Channel 1 VOLTS/DIV to .2 (IX) and set the
generator output for a 5-division display.
e. ADJUST— C4105 (see Figure 4-9) for the best front
corner on the square-wave display (see Figure 4-10 for
example). Disconnect the test equipment from the 442.
f. Set Channel 1 VOLTS/DIV to 10 m (IX).
b. Preset R126, Gain (see Figure 4-8), R4151 (Channel
1 Gain), and R4251 (Channel 2 Gain, see Figure 4-9), all
fully counterclockwise for minimum gain.
c. Set the Amplitude Calibrator for a 10 mV output
signal and connect it through a 50 fi cable to a dual-input
coupler connected to the Channel 1 and Channel 2 input
connectors.
d. ADJUST—R126 (Gain) for a centered vertical dis­
play amplitude of 4.8 divisions (set Channel 1 POSITION
as necessary to maintain a vertically centered display).
e. ADJUST— R4151 (CH 1 Gain) for a 5-division
centered vertical display amplitude (set Channel 1
POSITION as required).
g. Connect a 10X probe to the CH 1 input connector.
Connect the probe tip to a probe-tip-to-bnc adapter, the
adapter to a 50 Q bnc termination, and the termination to a
50 Q bnc 10X attenuator attached to the high-amplitude
output connector of the square-wave generator. Set the
generator for a 5-division, 1 kHz display.
h. Compensate the probe for the best front corner on
the displayed waveform.
i. Set the CH 1 VOLTS/DIV switch to 20 m (IX) and set
the generator for a 5-division display.
j. ADJUST—C4113 for the best flat top on the square
wave.
f. Press VERT MODE CH 2 button in.
k. Set CH 1 VOLTS/DIVto.2(1X) and set the generator
output for a 5-division display.
g. ADJUST—R4251 (CH 2 Gain) for a 5-division
centered vertical display amplitude (set Channel 2
POSITION as required). I. ADJUST—C4104 for the best flat top on the square
wave.
h. Disconnect the test equipment from the 442. m. Disconnect the test equipment from the 442.
4. Channel 1 Attenuator Compensation
a. Set:
VOLTS/DIV (CH 1)
AC-GND-DC (CH 1)
VERT MODE
SEC/DIV
MAGNIFIER
POSITION (all)
LEVEL
20 m (IX)
DC
CH 1
5 m
XI (button out)
As required
For a triggered display
5. CH 2 Attenuator Compensation
a. Set:
VOLTS/DIV (CH 2)
AC-GND-DC (CH 2)
VERT MODE
SEC/DIV
MAGNIFIER
POSITION (all)
20 m (IX)
DC
CH 2
5 m
XI (button out)
As required
4-20 REV A MAY 1980