Glossary
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80E00 Electrical Sampling Modules User Manual
Electrical Overstress (EOS)
Electrical overstress occurs when an electronic device is subjected to an
input voltage higher than the designed maximum tolerable level.
External Attenuation
A decrease in magnitude of current, voltage or power of a signal that is
outside the sampling module.
Impedance
The opposition to an AC signal in the wire. Impedance is very much like
resistance to a DC signal in a DC circuit. Impedance is made up of resistance
and inductive and capacitive reactance.
Incident Step
The electrical energy transmitted by the TDR step generator. An acquired
waveform shows this step and all reflections on the signal conductor.
Initialize
Setting the main instrument to a completely known, default condition.
Internal Clock
A trigger source generated internally within the instrument and used to
synchronize TDR step generators. Also available at the front panel Internal
Clock Output connector.
Rho (ρ)
When making TDR measurements, the ratio of the incident step to the
reflected step. A value of one (1) indicates complete reflection.
Setting
The state of the front panel and system at a given time.
TDR
Time-Domain Reflectometer: an instrument that sends out steps of energy
and measures the amplitude and time interval of the reflections. If the
velocity of the energy through the cable is known, distances to features can
be computed and displayed. Conversely, the speed that energy travels
through a cable of known length can also be computed. The way in which
the energy is reflected and the amount of the energy reflected indicate the
condition of the cable.
Time Domain Transmission (TDT)
A method of characterizing a transmission line or network by transmitting a
signal through the network and monitoring the output.
Trigger
An electrical event that initiates acquisition of a sample as specified by the
time base.
Waveform
The visible representation of an input signal or combination of signals.