ATMOSPHERICS.--Same as Static, which see.
ATTENUATION.--In Sending wireless telegraph and telephone messages the amplitude of the electric waves is damped out as the distance increases. This is called attenuation and it increases as the frequency is increased. This is the reason why short wave lengths will not carry as far as long wave lengths.
AUDIO FREQUENCY AMPLIFIER.--See Amplifier, Audio Frequency.
AUDIO FREQUENCY AMPLIFICATION.--See Amplification, Audio Frequency.
AUDIBILITY METER.--See Meter, Audibility.
AUDIO FREQUENCY.--See Frequency, Audio.
AUDIO FREQUENCY CURRENT.--See Current, Audio Frequency.
AUDION.--An early trade name given to the vacuum tube detector.
AUTODYNE RECEPTOR.--See Receptor, Autodyne.
AUTO TRANSFORMER.--See Transformer, Auto.