The radio-telephone alarm signal consists of two audio-frequency tones (one of 2200 Hz and the other of 1300 Hz) transmitted alternately, which gives a distinctive warbling sound that can be distinguished by ear through heavy traffic interference.
Umqondiso wesilumkiso wemfono-mfono nomathotholo unezandi ezibini zoqhagamshelwano oluvakalayo (enye 2200 H2 nenye ye1 300 Hz) ziqhagamshelana ngokushiya-shiyana enika isandi esintyilozayo esahlukileyo esinokwahlulwa ngendlebe kwingxolo eyenziwa zimoto okanye inqanawa.