There are a number of choices available to dim lighting systems with standard 115 or 277 volt, 60 cycle (per second) alternating current (AC) which is generated and transmitted in cycles of sine waves
. For 115-V AC service, the voltage curve rises from 0 volts to a peak of around +160 volts, in the first quarter of a cycle (1/240th of a second) and then the voltage curve descends in the second quarter cycle back down to zero.
To determine the specific effects of representative clipped-sample restoration algorithms, a testing regimen was formulated using both discrete sine waves
and voice information and then employed to evaluate two widely available commercial programs.
One rule is that only sine waves
can be used to describe signals.
DANFOSS DRIVES, LOVES PARK, ILL, The VLT drives restore and ensure sine waves
from power supply grids by performing real time analysis and actively imposing currents.
Adjustable symmetry allows the generator to produce a variety of pulse waveforms, ramp or sawtooth waves, and skewed sine waves
. Resolution is 10 mHz.
Combinations of circles and standing sine waves
might explain the observed shapes, agrees Tomas Bohr of the Technical University of Denmark.
The instrumentation (Figure 7) required includes a waveform generator to produce the sine waves
and potentiostat to control the potential.
The system produces a pure sine wave
, not clipped, quasi or modified sine waves
that are often produced by standard generators, according to the company Voltage stability is within [+ or -]1 percent and frequency stability is [+ or -]0.1 Hz.
The servo signal is a series of sine waves
that provide precise feedback to control the position of the read/write head on each of the 384 data tracks across the width of the tape.
An autoset function offers automatic detection and a choice of different views of sine waves
, square waves and video signals, including rising and falling edges, video lines and fields and FFT.
These characteristics depend in part on the type of signal you measure; transients, sine waves
, random noise, and signals with high-duty cycle all require different techniques.
Most NVH issues are analyzed in the frequency domain, which means that noise and vibration problems are analyzed in terms of sine waves
of specific frequency (hz or cycles per second).