ITU Q.24:1988
ITU Q.24:1988 Multifrequency Push-button Signal Reception
Table of Contents
1Introduction2Technicalparameters
2.1General
2.2Signalfrequencies
2.3Frequencytolerances
2.4Powerlevels
2.5Signalreceptiontiming
2.6Signalsimulationbyspeech
2.7Interferencebydialtone
2.8Interferencebyechoes
2.9Noiseimmunity