GLOSARIO DE TERMINOLOGÍA
Acoustic Audio Output (Receiver):
The acoustic audio output is the level registered on a sound level meter at a distance of 50 cm from the front of the receiver acoustic transducer.
Acoustic Microphone Sensitivity (Transmitter):
Acoustic microphone sensitivity is the acoustic sound pressure level which will produce 60% modulation of the transmitter.
Adjacent Channel Power Ratio (Transmitter):
Adjacent channel power ratio is that part of the total output power of a transmitter under defined conditions and modulation, which falls within a specified passband centered on the nominal frequency of either of the adjacent channels. This ratio is the sum of the mean power produced by the modulation plus the hum and noise of the transmitter to carrier power.
Audio Distortion (Receiver):
The audio distortion is the voltage ratio, usually expressed as a percentage of the rms value of the undesired signal to the rms value of the complete signal at the output of the receiver.
Audio Distortion (Transmitter):
The audio distortion is the voltage ratio, usually expressed as a percentage of the rms value of the undesired signal of the transmitter’s demodulated output to the rms value of the complete signal at the output of the transmitter’s demodulator.
Audio Frequency Response (Receiver):
The audio frequency response denotes the degree of closeness to which the audio output of a receiver follows a 6 dB per octave de-emphasis curve with constant frequency deviation over a given continuos frequency range.
Audio Frequency Response (Transmitter):
The audio frequency response is the degree of closeness to which the frequency deviation of the transmitter follows a prescribed characteristic.
Audio Low Pass Filter Response (Transmitter):
The Audio Low Pass Filter Response is the frequency response of the post limiter low pass filter circuit above 3000 Hz.
Audio Sensitivity (Receiver):
The audio sensitivity is the minimum level of modulation, which at maximum volume control setting, will produce rated audio.
Audio Sensitivity (Transmitter):
The audio sensitivity is the input rms voltage level that must be applied to the input terminals of the dummy microphone circuit to produce the standard test modulation. Any microphone automatic gain control must be disabled.
Auditory assistance device:
An intentional radiator used to provide auditory assistance to a handicapped person or persons. See 47 CFR 15.237.
Average Radiated Power Output (Transmitter):
The average radiated power of a licensed device is the equivalent power required, when delivered to a half-wave dipole antenna, to produce at a distant point the same average received power as produced by the licensed device.
Average Radiation Sensitivity (Receiver):
The average radiation sensitivity of a receiver is the power received by a half wave dipole measured into a 50 ohm load when substituted for a receiver that is receiving a signal at the reference sensitivity.
Biomedical telemetry device:
An intentional radiator used to transmit measurements of either human or animal biomedical phenomena to a receiver. FCC: 47 CFR 15.241.
Cable input selector switch:
A transfer switch that is intended as a means to alternate between the reception of broadcast signals via connections to and antenna and the reception of cable television service. FCC: 47 CFR 15.115.
Cable system terminal device (CSTD):
A TV interface device that serves, as its primary function, to connect a cable system operated under part 76 of this chapter to a TV broadcast receiver or any other subscriber premise equipment. FCC: 47 CFR 15.111, 15.118.
Carrier Attack Time (Transmitter):
Transmitter carrier attack time is the time required to produce 50% of steady-state carrier output power after changing the state of the transmitter from standby to transmit.
Carrier current system:
A system, or part of a system, that transmits radio frequency energy by conduction over the electric power lines. FCC: 47 CFR 15.221.
Carrier Frequency Stability (Transmitter):
The carrier frequency stability is the ability of the transmitter to maintain an assigned carrier frequency.
Carrier Output Power Rating (Transmitter):
The carrier output power rating for a transmitter for this service is the power available at the output terminals of the transmitter when the output terminals are connected to the standard transmitter load.
CE, C.E., CE Mark:
Indicates a piece of equipment complies with the appropriate EC standards.
Class A digital device:
A digital device that is marketed for use in a commercial, industrial or business environment, exclusive of a device which is marketed for use by the general public or is intended to be used in the home. FCC: 47 CFR 15.109.
Class B digital device:
A digital device that is marketed for use in a residential environment notwithstanding use in commercial, business and industrial environments. FCC: 47 CFR 15.109.
Conducted Spurious Emissions (Transmitter):
Conducted spurious emissions are emissions at the antenna terminals on a frequency or frequencies which are outside a band sufficient to ensure transmission of information of required quality for the class of communication desired.
Cordless telephone system:
A system consisting of two transceivers, one a base station that connects to the public switch telephone network and the other a mobile hand-set unit that communicates directly with the base stations. FCC: 15.233.
An unintentional radiator (device or system) that generates and uses timing signals at a rate in excess of 9,000 pules (cycles) per second and uses digital techniques. FCC: 47 CFR 15.109.
Federal Communications Commission
Field disturbance sensor:
A device that establishes a radio frequency field in its vicinity and detects changes in that field resulting from the movement of persons or objects within its range. FCC: 47 CFR 15.245.
Garage door openers:
See FCC: 47 CFR 15.231.
Hum and Noise Ratio (Receiver):
The Hum and noise ratio is the ratio of the rated output power to the residual output power in the absence of modulation, both measured at standard input signal level.
AM Hum and Noise Ratio (Transmitter):
AM hum and noise on the carrier is the ratio of the DC voltage detected from an unmodulated carrier to the detected peak ac voltage.
FM hum and Noise Ratio (Transmitter):
The FM hum and noise ratio is the ratio of the standard test modulation to the residual frequency modulation measured by the test receiver. This is to be performed with any audio compression/expansion circuit disabled.
Impulse Blanking Effectiveness (Receiver):
The impulse blanking effectiveness is the ability of the noise blanker to prevent and suppress the effects of short duration steep rise time pulses (such as ignition noise) in the presence of desired signals. This test applies only to units that incorporate noise blanker circuits that may be enabled or disabled.
Intermodulation Attenuation (Transmitter):
Intermodulation attenuation is the capability of a transmitter to avoid the generation of signals in the non-linear elements caused by the presence of the carrier and an interfering signal entering the transmitter via the antenna. It is specified as the ratio, in dB, of the power level of the third order intermodulation produce to the carrier power level.
Intermodulation Rejection (Receiver):
The intermodulation rejection is the ability of a receiver to prevent two unwanted input signals, with a specific frequency relation to the wanted signal frequency, from causing degradation to the reception of a desired signal. It is expressed as the ratio of the level of two equal level unwanted signals that cause the SINAD produced by the wanted signal 3 dB in excess of the reference sensitivity to be degraded to the standard SINAD, to the reference sensitivity.
Low power transmitters:
See FCC: 47 CFR 15.231.
Modulation Limiting (Transmitter):
Modulation limiting refers to the transmitter circuit’s ability to limit the transmitter from producing deviations due to modulation in excess of a rated system deviation.
Momentarily operated transmitters:
See FCC: 47 CFR 15.231.
Offset Channel Selectivity (Receiver):
The offset channel selectivity is the ratio of the level of an unwanted signal that causes the SINAD produced by a signal 3 dB in excess of the reference sensitivity to be degraded to the standard SINAD, to the reference sensitivity.
See Digital device.
Personal communication services. FCC: 47 CFR 15.319 and 47 CFR 24.
Power Line Conducted Spurious Emissions (Receiver):
The power line conducted spurious emission is energy that is generated or amplified in a receiver and appears between each power line terminal that connects to a public utility line and ground.
Radiated Spurious Emission (Receiver):
The radiated spurious emission is the electromagnetic energy generated or amplified in a receiver and radiated from the receiver or by the antenna, or by all control, audio, and power leads.
Radiated Spurious Emissions (Transmitter):
Radiated spurious emissions are emissions from the equipment when transmitting into a non-radiating load on a frequency or frequencies which are outside an occupied band sufficient to ensure transmission of information of required quality for the class of communications desired.
Receiver Attack Time (Receiver):
Receiver attack time is the time required to produce audio power output after application of a modulated input signal.
Receiver Closing Time (Receiver):
The receiver closing time is that period of time between removal of an input signal and squelch closure.
Reference Sensitivity (Receiver):
The reference sensitivity is the level of receiver input signal at a specified frequency with specified modulation which will result in the standard SINAD at the output of the receiver.
Radio frequency is a frequency useful for radio transmission, roughly 10 kHz to 100 GHz.
Radio frequency interference
A receiver that automatically switches among four or more frequencies in the range of 30 to 960 MHz and which is capable of stopping at and receiving a radio signal detected on a frequency. FCC: 47 CFR 15.109.
Security system transmitters:
See FCC: 47 CFR 15.231.
Sideband Spectrum (Transmitter):
The term transmitter Sideband Spectrum denotes the sideband energy produced at a discrete frequency separation from the carrier up to the test bandwidth (see section 18.104.22.168) due to all sources of unwanted noise within the transmitter in a modulated condition.
Signal Displacement Bandwidth (Receiver):
The signal (frequency) displacement bandwidth is the input signal frequency displacement that reduces the SINAD produced by a signal 6 dB in excess of the reference sensitivity, to the standard SINAD.
A technique whereby radio communications energy is spread over a wide bandwidth, includes both direct sequence and frequency hopping equipment. FCC: 47 CFR 15.247.
Spurious Response Rejection (Receiver):
The spurious response rejection is the ability of a receiver to prevent single unwanted signals from causing degradation to the reception of a desired signal. It is expressed as the ratio of the level of a single unwanted input signal that causes the SINAD produced by a wanted signal 3 dB in excess of the reference sensitivity to be degraded to the standard SINAD, to the reference sensitivity.
Squelch Blocking (Receiver):
Squelch blocking is the tendency of the receiver squelch circuit to close in the presence of modulation of the input signal.
Television (TV) broadcast receiver:
A device designed to receive television pictures that are broadcast simultaneously with sound on the television channels authorized under part 73 of this chapter. FCC: 47 CFR 15.109.
A device used to alternate between the reception of over-the-air radio frequency signals via connection to an antenna and the reception of radio frequency signals received by any other method, such as from a TV interface device. FCC: 47 CFR 15.115.
Transient Frequency Behavior (Transmitter):
Transient Frequency Behavior is a measure of the difference, as a function in time, of the actual transmitter frequency to the assigned transmitter frequency when the transmitted RF output power is switched on or off.
Transmitter Modulation Limiting (Transmitter):
Modulation limiting refers to the transmitter circuit’s ability to prevent the transmitter from producing deviations due to subaudible signaling and excessive voice modulation in excess of a rated system deviation.
Transmitter Stability into VSWR (Transmitter):
Transmitter stability into VSWR is the ability of a transmitter not to produce any spurious greater than allowed for the conducted spurious emissions when operated in a load different from the standard load.
TV interface device:
An unintentional radiator that produces or translates in frequency a radio frequency carrier modulated by a video signal derived from an external or internal signal source, and witch fees the modulated radio frequency energy by conduction to the antenna terminals or other non-baseband input connections of a television broadcast receiver. FCC: 47 CFR 15.115, 15.118.