| 摘要 |
<p>The apparatus is for digitizing a frequency shift key modulated data signal which has subsequently been demodulated. The apparatus comprises a differentiating circuit (3) arranged to receive the demodulated data signal, and produce differentiated pulses at an output thereof. First and second comparators (7,9) are arranged to receive the differentiated pulses, and compare the pulses with respective reference voltages (REF1,REF2) to generate output pulses when pulses above and below the respective reference voltages are detected. The outputs of the comparators (7,9) are connected to the set (S) and reset (R) inputs respectively of a flip-flop (11), causing a digitized form of the input demodulated signal to be generated at an output of the flip-flop (11). <IMAGE></p> |
