Tektronix 310A, Инструкция по эксплуатации, Страница: 63 / 132

Performance Check/Calibration—Type 310A
Fig. 5 -8 . Lo cation o f V E R T G A IN A D J (raar panel).
11. Check/Adjust Vertical Preamplifier Gain
a. Set the VO LT S /D IV switch to .01.
b. Set the standard amplitude calibrator for a 50
millivolt squarewave output.
c. Center the display about the center horizontal line
with the VERTICAL POSITION control.
d. C H EC K -C R T display for five divisions *0.15 divi
sion vertical deflection (within 3%). Since the signal Is AC
coupled in this position, some waveform tilt is evident in
the CRT display. Measure the amplitude between the front
corners of the positive and negative portions of the square
wave to eliminate amplitude errors due to the tilt.
e. ADJUST Preamp Gain adjustment, R322 (see Fig.
5-9), for exactly five divisions vertical deflection at the
center vertical line.
cal deflection within 3% in each position of the VO LTS/
D IV switch.
TABLE 5-1
Vertical Deflection Accuracy
VO LTS /D IV
switch
setting
Standard
amplitude
calibrator
output
Vertical
deflection
in divisions
Maximum
error for
±3% accuracy
(divisions)
.01 Checked in previous step
.02 0.1 volt 5
±0.15
.05 0.2 volt
4
±0.12
.1 0.5 5
±0.15
.2
1 volt 5
±0.15
.5 2 volts
4 ±0.12
1 5 volts
5
±0.15
2
10 volts
5
±0.15
5 20 volts 4 ±0.12
10 50 volts
5
±0.15
26 100 volts
5
±0.15
50 100 volts
2
±0.06
13. Check Variable Volts/Division Control Range
a. Change the following control settings
V O LT S /D IV .1
Input Coupling AC
b. Set the standard amplitude calibrator for a 0.5-volt
square wave output.
c. Center the display about the center horizontal line
with the VERTICAL POSITION control
12. Check Vertical Deflection Factor Accuracy
a. CHECK-Using the VO LTS /D IV switch and standard
amplitude calibrator settings given in Table 5-1, check vorti
Fig. 5 -9 . Location o f Preamp G ain adjustm ent (le ft side).
d. CHECK Rotate the Variable VO LTS /D IV control
fully counterclockwise. Display must be reduced to two
divisions or less (indicates adequate range for continuously
variable deflection factor between the calibrated steps).
UNCALIBRATED VE R TIC A L light must be on when Vari
able VO LT S /D IV control Is not In the CALIBRATED
Position.
14. Check Input Coupling Switch Operation
a. Set th e V a ria b le V O L T S /D IV c o n tro l to
CALIBRATED.
b. Set the standard amplitude calibrator for a 0.2 volt
square wave output.
c. Center the display about the center horizontal line
with the VER TIC A L POSITION control
d. Set the Input Coupling switch to DC.
e. CHECK-Bottom of the displayed square wave near
the center horizontal line.
5 13