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The walkie talkie used by security service companies has the following main functions:
Frequency error: the difference between unmodulated carrier frequency and allocated frequency.
Output Carrier Power: Average power given to the transmission line by the transmitter rack during a radio frequency cycle without modulation
Clutter Scattering Weight: A signal having a significant weight at a discrete frequency or in a narrow band, in addition to the modulation weight near the carrier and its transmission bandwidth. Contains harmonic and non harmonic and parasitic weights.
Neighborhood power: The part of the total output power that falls within the regular bandwidth of any adjacent channel in a transmitter operating in a channel-differentiated system under regular modulation conditions.
Audio Distortion: The ratio of the RMS value of the distorted sinusoidal signal to the RMS value of the full signal is removed. The distorted sinusoidal signal is expressed as a percentage. The distorted sinusoidal signal includes Harmonic weight, power ripple and non-harmonic weight.
Modulating the constraints: transmitter audio circuits avoid modulating the ability to exceed maximum permitted offsets.
Extra Audio Output Power: The power available when the receiver's output connects to a regular load under regular operating conditions.
Reference Sensitivity: Also known as the maximum available sensitivity, at regular frequencies and modulations, the receiving output end produces a quasi-signal-to-noise ratio (12Dbsinad) input signal level.
Selectivity: characterizing the ability of the receiver to use input signals to resist useless input signals. After measuring the neighboring signal selectivity, the common channel is identified by such functions as scratching, blocking, spurious response, intermodulation immunity and so on.
It should be pointed out that the target of intercom's electrical function is different in different countries and regions as well as in different occupations, so the size of the target can not be judged simply according to the target value, but also based on detailed specifications. For example: Intermodulation immunity target, European code, FCL code, Hong Kong Telecommunication Bureau code, because of the different measurement methods, in measuring the same machine, the target value is very different.
Above is about the radio interphone performance introduction, I hope to help you, want to know more content, you can pay attention to our website, there are more wonderful content in the website.