Tektronix 503, Инструкция по эксплуатации

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g. Check— The display amplitude should be 5 cm ±
1.5 mm.
6. Check Variable Control Ratio— Vertical
a. Requirement— Display amplitude with control in CALI­
BRATED position should be > 2 .5 times the display am pli­
tude with the control in full counterclockwise position.
b. Rotate the control fully counterclockwise.
c. Check— Display amplitude should be 2 cm or less,
indicating a ratio of >2.5:1.
d. Return the VARIABLE control to the CALIBRATED posi­
tion.
7. Check 1 m V/CM Gain— Vertical
a. Requirement— Vertical deflection accuracy ± 3 % .
b. Change the Standard Amplitude Calibrator output to
5 millivolts.
c. Change the VERTICAL SENSITIVITY switch to 1 mV/CM,
and adjust the VERTICAL POSITION control to center the
display, if necessary.
d. Check— Display amplitude of 5 cm, ± 1 .5 mm (3%).
8. Check .2 VOLTS/CM Gain— Horizontal
a. Requirement— Horizontal deflection accuracy ± 3 % .
b. Set the VERTICAL +INPU T selector switch to GND.
c. Set HORIZONTAL +INPU T switch to DC.
d. Set the HORIZONTAL DISPLAY switch to HORIZ.
AMPLIFIER (SWEEP DISABLED).
CAUTION
W henever the sweep is d isa b le d , check th a t the
CRT beam INTENSITY control is adjusted to p re ­
vent dam age to the CRT phosphor.
e. Set the Standard Amplitude Calibrator to supply a
1-volt square wave, and connect the signal to the HORI­
ZONTAL + INPUT connector.
f. Set the HORIZONTAL SENSITIVITY switch to .2
VOLTS/CM.
g. The display should now consist of two dots spaced
horizontally in the graticule area. Center the display with
the HORIZONTAL POSITION control.
h. Check— The dot spacing should be 5 cm -t 1.5 mm.
9. Check Variable Control Ratio— Horizontal
a. Requirement— Horizontal deflection with the cont/ol
in the CALIBRATED position should be > 2 .5 times the hori­
zontal deflection with the control in the full counterclockwise
position.
b. Rotate the HORIZONTAL VARIABLE control fully coun­
terclockwise.
Performance Check— Type 503
c. Check— The dot spacing should be < 2 cm, indicating
a ratio of >2.5:1.
d. Return the VARIABLE control to the CALIBRATED posi­
tion.
1 0 . Check 1 m V /C M G a in — H o riz o n ta l
a. Requirement— Horizontal deflection accuracy ± 3 % .
b. Change the Standard Amplitude Calibrator to 5 m illi­
volts.
c. Change the HORIZONTAL SENSITIVITY switch to 1
mV/CM.
d. Check— Dot spacing 5 cm ± 1 .5 mm.
11
. Check C om pression o r E xpansion—
H o riz o n ta l
a. Requirement— < 1 .5 mm amplitude change in a 2-cm
display.
b. Change the HORIZONTAL SENSITIVITY switch to .2
VOLTS/CM.
c. Change the Standard Amplitude C alibrator to 0.5 V
output.
d. W ith the VARIABLE control, adjust the dot spacing
for exactly 2 cm, and center the display horizontally and
vertically.
e. W ith the HORIZONTAL POSITION control, move the
right-hand dot to the 10-cm vertical graticule line.
f. Check— Dot spacing 2 cm ± 1 .5 mm.
g. Move the left-hand dot to the left edge (0-cm) of the
graticule.
h. Check— Dot spacing 2 cm ± 1 .5 mm.
i. Return the VARIABLE control to the CALIBRATED posi­
tion.
12.
C heck A m p lifie r B a la n c e — H o riz o n ta l (DC
C o m m o n M o d e Rejection)
a. Connect an additional 50-ohm cable to the Standard
Amplitude Calibrator output, using a UHF T adapter, and
a quick-connect adapter on the output end of the cable.
b. Set the HORIZONTAL — INPUT to DC, and connect
the cable added in step (a) to the — INPUT connector.
c. Change the Standard Amplitude Calibrator output to
5 volts, and the HORIZONTAL SENSITIVITY switch to .2
VOLTS/CM.
d. The display will be two dots spread horizontally. W ith
the HORIZONTAL POSITION control, move the display
to the right-hand and then to the left-hand vertical grati­
cule line.
e. Check— The total horizontal amplitude of the display
should not exceed 2.5 mm anywhere in the graticule area
(CMRR 100:1).
c)
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