In addition to the authentication and acknowledgment procedures which precede and follow the sending of the go messages, again in special codes, each message also contains an `` internal authenticator '', another specific signal to convince the recipient that he is getting the real thing.

By this standard, it is determined that where two stations operating on the same frequency are involved, objectionable interference from station A exists at any point within the service area of station B where station A's signal is of an intensity one-twentieth or more of the strength of station B's signal at that point.

For this reason, the more uncertain skywave service was denominated `` secondary '' in our rules, as compared to the steadier, more reliable groundwave `` primary service '', and, for both skywave service and skywave interference, signal strength is expressed in terms of percentage of time a particular signal-intensity level is exceeded -- 50 percent of the time for skywave service, 10 percent of the time for skywave interference.

The design of a mechanical interlocking frame is much like a mechanical puzzle, but once understood, the principles can be applied to any track and signal arrangement.

If the lever is pulled to clear a signal or move a switch, the tappet moves a short distance lengthwise at the same time.

By this scheme, pulling one signal to clear locks all the other switch and signal levers in safe positions until the first signal is again restored to normal.

As an engineer approaches the plant the position of the home signal is seen in advance when he passes the `` distant '' signal located beyond the limits of the interlocking plant.

In some low-speed situations, the distant signal is fixed at caution.

The video signal is amplified and then switched, in synchronism with the three ultraviolet light sources which are sequenced by the rotating mirror so that during one-twentieth of a second only one wavelength, corresponding to red, green, or blue, is seen.

The electrical signal from the autocollimator is amplified and supplied to the Z-gyro torquer.

Essentially, the stator or reference portion of the pickoff is established with respect to the true heading direction, and the platform is turned either manually or automatically until the angular electrical pickoff signal is reduced to zero.

`` The pattern '', says Dr. Morton Schillinger, psychologist at New York's Lincoln Institute for Psychotherapy, `` is for the husband to hover about anxiously and eagerly, virtually trembling in his hope that she will flash him the signal that tonight is the night ''.

I said `` Darn it, that's the automatic signal that shows when the ignition key is on.

As soon as that one man is appointed by himself or the others or by a signal from Spencer, we are going to be rushed.

Any information may be conveyed by an analog signal ; often such a signal is a measured response to changes in physical phenomena, such as sound, light, temperature, position, or pressure.

A checkered backdrop is often used to signal transparency.

Audio signal processing, sometimes referred to as audio processing, is the intentional alteration of auditory signals, or sound, often through an audio effect or effects unit.

It is often used in signal processing for analyzing functions or series of values, such as time domain signals.

* MRI of the brain — often shows high signal intensity in the caudate nucleus and putamen bilaterally on T2-weighted images.

In these applications, an important goal is often the recovery of information encoded ( or modulated ) onto the AC signal.

In digital logic and computing, a counter is a device which stores ( and sometimes displays ) the number of times a particular event or process has occurred, often in relationship to a clock signal.

Polling ( often called scanning in this case ) is done by activating each x line in sequence and detecting which y lines then have a signal, thus which keys are pressed.

However, often, the required output signal is another analog output signal, which requires a digital-to-analog converter ( DAC ).

The widespread adoption of digital video has also drastically reduced the bandwidth needed for a high-definition video signal ( with HDV and AVCHD, as well as several commercial variants such as DVCPRO-HD, all using less bandwidth than a standard definition analog signal ) and tapeless camcorders based on flash memory and often a variant of MPEG-4.

Equivalently, the DFT is often thought of as a matched filter: when looking for a frequency of + 1, one correlates the incoming signal with a frequency of − 1.

An electronic oscillator is an electronic circuit that produces a repetitive, oscillating electronic signal, often a sine wave or a square wave.

Oscillators are often characterized by the frequency of their output signal:

LC oscillators are often used at radio frequencies, when a tunable frequency source is necessary, such as in signal generators, tunable radio transmitters and the local oscillators in radio receivers.

Square-wave relaxation oscillators are used to provide the clock signal for sequential logic circuits such as timers and counters, although crystal oscillators are often preferred for their greater stability.

Product mixers are often used in conjugation with an oscillator in the communications field to modulate signal frequencies.

The exact choice of quiescent current, the standing current through both devices when there is no signal, makes a large difference to the level of distortion ( and to the risk of thermal runaway, that may damage the devices ); often the bias voltage applied to set this quiescent current has to be adjusted with the temperature of the output transistors ( for example in the circuit at the beginning of the article the diodes would be mounted physically close to the output transistors, and chosen to have a matched temperature coefficient ).

The frequency spectrum of an actual FM signal has components extending infinitely, although their amplitude decreases and higher-order components are often neglected in practical design problems.

In a device that does not display text, a simple program to produce a signal, such as turning on an LED, is often substituted for " Hello world " as the introductory program.

They generally use individual piezo-electric transducers one per string often in combination with small internal microphones to produce a direct output mixed electrical signal.

Captain Clemens' signal shot sent the men hurrying to their waiting teams.

At two thirty he sent Fujimoto to the top of the wall at the northeast corner of the mission to keep an eye on the ridge road and give a signal when he first glimpsed the approach of Kayabashi's party.

AM works by varying the strength of the transmitted signal in relation to the information being sent.

When the key was not in use, that switch was kept closed, so that a signal was continually sent.

Each character in the alphabet is represented by a series of bits, sent over a communication channel such as a telegraph wire or a radio signal.

If u ( t ) is the control signal sent to the system, y ( t ) is the measured output and r ( t ) is the desired output, and tracking error, a PID controller has the general form

At the headend the radio frequency electrical signal carrying all the channels is modulated on a light beam and sent through the fiber.

This service involves installing a special telephone interface at the customer's premises that converts the analog signals from the customer's in-home wiring into a digital signal, which is then sent on the local loop ( replacing the analog last mile, or Plain old telephone service ( POTS )) to the company's switching center, where it is connected to the Public switched telephone network ( PSTN ).

The behavior of the electrons gives the impression of some signal having been sent to all possible points of contact that would have nullified all but one of them, or, in other words, would have preferentially selected a single point to the exclusion of all others.

Group 1 and 2 faxes are sent in the same manner as a frame of analog television, with each scanned line transmitted as a continuous analog signal.

When a pilot moves the control column ( or sidestick ), a signal is sent to a computer ( analogous to moving a game controller ) the signal is sent through multiple wires ( channels ) to ensure that the signal reaches the computer.

His bass signal is sent via a Samson wireless unit to an Avalon U5 DI.

The speaker-level signal from the Quadravalve is sent to a Palmer PD-05 speaker emulator, which provides adequate load for the tube amplifier and attenuates the signal down to line level.

At the telegraph office closest to the destination of the letter, the signal was transferred back into a hardcopy format and sent as a normal mail to the person's home.

The signal sequence is cleaved in the endoplasmic reticulum, and the resulting 215 kDa pro-LPH is sent to the Golgi, where it is heavily glycosylated and proteolytically processed to its mature form.

In Pyramids of Mars ( 1975 ) the Fourth Doctor defeats Sutekh, last of the Osirians, who had been imprisoned for his crimes beneath a pyramid, with a signal to keep him paralyzed sent from a Martian pyramid.

* Network Measurement Report, the message that is sent by a mobile phone ( e. g. GSM ) to the network containing the signal strengths of the surrounding antennas