1. In a method for detecting the presence of a speech signal in a voice channel signal, said method providing an active channel indication when said speech signal presence is detected in said voice channel signal and an idle channel indication when the absence of said speech signal presence is detected in said voice channel signal, said voice channel signal being capable of containing both said speech signal and background noise, said speech signal having an envelope associated therewith having a magnitude variable over time, said background noise having an evelope associated therewith having a magnitude substantially constant over time, said voice channel signal having an envelope associated therewith having a magnitude dependent on said magnitudes of said speech signal and said background noise envelopes; said method being of the type wherein a first evaluation of said voice channel signal envelope magnitude is made over a first time domain to obtain a first resultant output signal and compared with a first preset threshold level for providing a first active channel condition when said first evaluation resultant output signal exceeds said first preset level, said first level being preset at a level higher than said background noise envelope magnitude; the improvement comprising the steps of making a second evaluation of said voice channel signal envelope magnitude over a second time domain to obtain a second resultant output signal, said second time domain being different from said first time domain, determining the difference in magnitude between said first and second evaluation resultant output signals, and comparing said difference with at least a first predetermined value and providing a second active channel condition when said difference exceeds said first predetermined value and a first idle channel condition when said difference is less than said first predetermined value, said active channel indication being provided when either said first or second active channel conditions are present, said idle channel indication only being provided when said first idle channel condition is present and neither said first or second active channel condition is present.