Tektronix 502A, Instruction Manual

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SECTION 1
CHARACTERISTICS
General
The Tektronix Type 502A Oscilloscope provides linear
dual-beam displays with a wide range of sweep rates com­
bined with high input sensitivity. In addition, the Type
502A may be used to provide dual-beam X-Y displays at
medium
sensitivities, and single-beam X-Y displays at high
sensitivities. Vertical amplifiers for both beams may be
operated with single-ended inputs for conventional operation,
or with differential inputs for cancellation of common-mode
signals. The wide range of operational modes available
makes the Type 502A adaptable to a great many industrial
and scientific applications.
VERTICAL-DEFLECTION SYSTEM
Characteristics at each input terminal
Direct connection —1 megohm paralleled by 47 pf.
With P6006 Probe—10 megohms paralleled by approx.
9 pf.
Deflection factors
Seventeen calibrated deflection factors from 0.1 mv/cm to
20 v/cm accurate within 3%.
Continuously variable deflection factors are available from
0.1 mv/cm to approximately 50 v/cm. However, when the
variable is used the frequency response in each range of the
SENSITIVITY control will be slightly reduced.
Frequency response
Frequency response characteristics of the Type 502A vary
with settings of the SENSITIVITY controls. Typical readings
are as follows:
.1 mv/cm 50 kc
.2 mv/cm 100 kc
1 mv/cm 200 kc
50 mv/cm 400 kc
.2 v/cm 1 mc
Differential input rejection ratio
The rejection ratios specified below apply if the signal
voltage at the Input connector does not exceed specified
limits. The signal limits for dc coupling are, + or — 2 volts
with respect to ground for settings of the SENSITIVITY con­
trol from 0.1 mv/cm to .2 v/cm, + or — 20 volts with respect
to ground for settings from .5 v/cm to 2 v/cm, and + or —
200 volts with respect to ground for settings from 5 v/cm to
20 v/cm. For ac-coupling, the signal limits are 2 volts
peak-to-peak from 0.1 mv/cm, to .2 v/cm, 20 volts peak-to-
peak from .5 v/cm to 2 v/cm, and 200 volts peak-to-peak
from 5 v/cm to 20 v/cm.
The DC common mode rejection ratios are measured
with a common sine-wave signal which is applied to both
inputs
of one vertical amplifier simultaneously. The sine­
wave signal has a constant amplitude of 2 volts and a
frequency as stated in the table below.
DC Common Mode Rejection Ratio
† A rejection ratio of 40,000:1 can only be obtained if the DC
BAL control has been properly adjusted.
Sensitivity Setting
(Sine-wave output
Ratio
held at a constant
Frequency
amplitude of 2 volts)
.2 VOLTS PER CM 1 kc 1 00:1
.2 mVOLTS PER CM 1 kc 20,000:1
†
.1 mVOLTS PER CM 1 kc 40,000:1
.2 VOLTS PER CM 400 kc 50:1
.2 mVOLTS PER CM 100 kc
1000:1
.1 mVOLTS PER CM 50 kc 2000:1
HORIZONTAL-DEFLECTION SYSTEM
Sweep rates
Twenty-one calibrated sweep rates from 1 μsec/cm to
5 sec/cm.
Accuracy typically within 1 % of full scale; in all cases,
within 3%
of full scale.
Continuously variable sweep rates are available from
1 μsec/cm to approximately 2.5 sec/cm.
Magnifier
Expands sweep 2, 5, 10, or 20 times. Calibration of
magnified sweep rates accurate within 3% for sweep rates
which do not exceed the maximum calibrated rate of
1 μisec/cm.
Unblanking
DC coupled.
Triggering signal requirements
Internal—a signal producing 2 mm vertical deflection
on either the UPPER or LOWER BEAM.
External
— 0.2 volts to 10 volts on either polarity.
Triggering signal sources
UPPER BEAM, LOWER BEAM, external, or line.
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