Signal selection and fault detection apparatus

Claim 1

Apparatus for selecting one of several input signals comprising: a plurality of equalizer channels, each equalizer channel processing one of said input signals and compensating said signal with respect to a midvalue selected signal; midvalue selector means having a plurality of inputs and an output, each input coupled to one of the equalizer channels for producing at its output the midvalue one of said compensated input signals; and fault detector means for identifying as a fault each compensated input signal which deviates from the midvalue selected signal by a predetermined value and, in response thereto, isolating the identified compensated input signal from said midvalue selector inputs and substituting therefor as an input to the midvalue selector the output signal from the midvalue selector, said fault detector means further comprising means for directly coupling the remaining compensated signal as the output from the signal selector apparatus responsive to the isolation of all identified compensated input signals save one from the inputs to the midvalue selector.

Claim 8

A method for selecting one of several input signals comprising the steps of: (a) equalizing each input signal with respect to a midvalue selected signal and thereby producing a plurality of compensated input signals; (b) midvalue selecting the midvalue one of said plurality of compensated input signals; (c) identifying as a fault each compensated input signal which deviates from the midvalue selected signal by a predetermined value; (d) isolating each fault identified compensated input signal from said midvalue selecting step (b) and substituting in its place the selected midvalue signal; and (e) providing the remaining compensated input signal as the selected output signal responsive to the condition of the isolation of all compensated input signals save one.

Claim 9

A method for selecting one of several input signals comprising the steps of: (a) equalizing each input signal with respect to a midvalue selected signal and thereby producing a plurality of compensated input signals; (b) midvalue selecting the midvalue one of said plurality of compensated input signals; (c) identifying as a fault each compensated input signal which deviates from the midvalue selected signal by a predetermined value; (d) isolating each fault identified compensated input signal from said midvalue selecting step (b) and substituting in its place the selected midvalue signal; and (e) providing the remaining compensated input signal as the selected output signal responsive to the condition of the isolation of all compensated input signals save one.