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In the scrambling system, an analog audio signal is converted into a digital signal to provide a sequence of digital signal samples corresponding to the analog audio signal. Each digital signal sample is compressed to provide compressed signal samples having a sign bit, three exponent bits and seven

In the scrambling system, an analog audio signal is converted into a digital signal to provide a sequence of digital signal samples corresponding to the analog audio signal. Each digital signal sample is compressed to provide compressed signal samples having a sign bit, three exponent bits and seven mantissa bits. Each bit of each compressed signal sample is exclusive-OR\d with a unique keystream to thereby scramble the audio signal. A Hamming code generator generates code bits for correcting singular errors in a combination of the sign bit, the exponent bits and the code bits; and a parity bit generator generates a parity bit for detecting double errors in a combination of the sign bit, the exponent bits and the code bits and for further detecting an error in the most significant mantissa bit and/or the parity bit. The bits from a plurality of successive compressed, error-encoded signal samples are interleaved and serialized in order to separate the bits from any single sample by at least a predetermined duration associated with an FM discriminator click. The serialized, interleaved, error-encoded, compressed signal samples are combined to provide two-bit digital words. The digital words are converted to digital PAM data signals which when converted to an analog signal by digital-to-analog conversion, provide a pulse-amplitude-modulated signal having a level related to the binary value of the digital words. The digital PAM data signals are converted to an analog signal to provide the pulse-amplitude-modulated signal. The descrambler system descrambles the scrambled audio signal by a process that is the converse of the scrambling process. Singular errors in a scrambled signal sample are detected and corrected by a Hamming error corrector. Double errors in a scrambled signal sample are detected by a parity bit check and compensated for by repeating the last received error free signal sample.

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A system for scrambling an audio signal, comprising means for converting an analog audio signal into a digital signal to provide a sequence of digital signal samples corresponding to the analog audio signal; means for compressing each digital signal sample to provide compressed signal samples having

A system for scrambling an audio signal, comprising means for converting an analog audio signal into a digital signal to provide a sequence of digital signal samples corresponding to the analog audio signal; means for compressing each digital signal sample to provide compressed signal samples having a sign bit, a first given number of exponent bits and a second given number of mantissa bits; means for interleaving bits from a plurality of successive samples; and means for serializing the interleaved bits in order to separate the bits from any single sample by at least a predetermined duration associated with a given type of interference signal; wherein the audio signal includes stereo audio components and the aforesaid means provide separate interleaved, compressed signal samples for the respective stereo audio components, the system further comprising means for combining individual bits from the separate interleaved, compressed signal samples for the respective stereo audio components to provide a series of two-bit digital words, wherein the exponent bits and the code bits occupy the bit position in the digital words having the lower error rate and the mantissa bits occupy the other bit position in the digital words; and means for converting the digital words to an analog signal having a level related to the binary value of the digital words.