Tektronix 323, Instruction Manual

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Operating Instructions— Type 3 2 3
signal musl supply with energy when the signal is applied
to the input of a circuit.
Input RC Characteristics—The value of capacitance and DC
resistance present at the input of the oscilloscope. Also
referred to as input impedance.
Internal Triggering— Using a sample of the signal present in
the vertical amplifier as a triggering signal source.
Jitter—An aberration of a repetitive display indicating in­
stability of the signal or of the oscilloscope. May be random
or periodic, and is usually associated with the time axis.
Lissajous Figure—A special case of an X-Y display, produced
by simultaneous application of sine waves to the vertical
and horizontal deflection plates. Useful for determining
phase and frequency relationships.
Load—The impedance offered by a circuit or device. The
lower the impedance, the greater the loading effect.
Loading— Requiring a circuit to supply energy to another
circuit. The term is often associated with the effect caused
by attaching test equipment to a circuit.
Magnified Sweep— Enlarged portion of a sweep (usually
horizontal). In the Type 323 Oscilloscope, the sweep can
be magnified so that 1 division of display is viewed over
10 divisions through use of the X 10 HORIZ MAG control.
Noise— Any extraneous electrical disturbance tending to in­
terfere with the normal display.
Open Circuit—A discontinuous circuit.
Overshoot— In the display of a step function (usually of
time), that portion of the waveform which, immediately
following the step, exceeds its nominal or final amplitude.
Period—The time elapsing between occurrence of identical
points in an AC or recurring transient event. It usually
refers to repetitive waveforms and is the reciprocal of their
frequency.
Phase Shift—The change in the phase angle (of a sinusoidal
waveform) which is introduced when the waveform passes
through a network.
Phosphor—The substance coating the inner face of a cath­
ode-ray tube. It emits light when bombarded by electrons.
Plate— In a cathode-ray tube, any one of the deflection
plates.
Preventive Maintenance— Cleaning, inspecting and lubricat­
ing equipment to insure continued reliable operation.
Probe— A pointed metal tip within an insulating handle.
Used for temporarily connecting to a signal source. It can
include attenuation capability. Generally includes the as­
sociated cable and connector.
Probe Tip—That part of a probe which makes contact with
the signal pickoff point.
Pulse Width—The time between specified equal amplitude
points on both slopes of an electrical pulse. Usually meas­
ured at the 50% amplitude points.
Push-Pull— Currents or voltages which are equal in ampli­
tude but opposite polarity. Also defines a circuit which
has that type of response.
Reflection— A signal caused by reflected signal energy.
Usually thought of as energy returned by a transmission
line which is not terminated in its characteristic impedance,
or which has impedance discontinuities within it.
Response Characteristics— A quantitive description of the
input-output characteristics of a device or circuit. Usually
amplitude versus frequency response.
Retrace— Return of the spot to the left of the cathode-ray
tube face upon completion of a horizontal sweep. Also
that portion of the sweep waveform which causes the spot to
return.
Retrace Blanking—The process of creating a CRT blanked
condition during Retrace.
Return Trace— A path created by the spot during retrace.
Should not be seen during normal sweep operation.
Ringing—A damped oscillatory transient occurring in a sys­
tem as a result of a sudden change of input.
Ripple— AC superimposed on a DC level. Commonly associ­
ated with filtered DC power supplies.
Risetime—The interval between the instants at which the
instantaneous amplitude first reaches specified lower and
upper limits. In the display of a step function of time, these
limits are 10% and 90% of the nominal or final amplitude
of the step.
Rounding— In the display of a step function (usually of time),
the loss of the corner following the step.
Sawtooth Waveform— A waveform containing a linear sloped
rise and return to its initial value, the two portions usually
of unequal duration. Commonly describes the waveform
created by the oscilloscope horizontal sweep generator.
Semi-conductor Device— Any one of several devices made of
semi-conductor material; usually diodes or transistors.
Sensitivity—See deflection sensitivity.
Short Circuit—A low impedance connection across circuit
branches or power sources.
Signal Pickoff Point—A point at which a circuit is tapped
into to provide a signal for any of various purposes, such
as oscilloscope display.
Signal Source—The point of origin of a signal. Also used
to describe Signal Pickoff Point.
Slope— In oscilloscope waveform presentations, the term
describes the direction and ratio of change of vertical de­
flection related to change of horizontal deflection (AE/At).
Source— The point of derivation of power or of a specific
type of power (line, +300 V, —150 V, battery). Also the
element in a Field Effect Transistor which operationally cor­
responds with the cathode of a triode vacuum tube.
Sweep— An independent variable of a display; unless other­
wise specified, this variable is a linear function of time, but
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