Abstract: A Manchester decoder blanks random transitions prior to the reception of a valid Manchester encoded signal. Specifically, the decoder according to the present invention comprises a data input, and edge detector, and a blanking device. The edge detector is used to detect edges in a signal which is received by the data input. Thus, in the event that edges are not detected at predetermined intervals (signifying that a valid signal is not being received), the blanking device blanks a data output of the decoder. Advantageously, the decoder circuit filters random transitions prior to the reception of a valid Manchester encoded signal, is of simple construction, and may be implemented in conjunction with a decoder circuit which is used to separate the Manchester encoded signal into its data and clock components.