A system comprising: an accelerometer having a first vibrating beam providing a first square wave output and a second, complementary vibrating beam providing a second square wave output; an enhancement circuit , coupled to the first and second square wave outputs of the accelerometer, the enhancement circuit comprising: a counter that counts a number of leading edges of pulses in each of the first and second square wave outputs of the accelerometer over a selected period of time; a comparator , responsive to the counter, that determines when the count in the selected period of time for either of the first and second square wave outputs falls outside a normal operating range of values; and an output circuit , responsive to the comparator, that is adapted to replace the count value of one of the first and second square wave outputs with a value in the normal operating range when the comparator determines that the count value for the one of the first and second square wave output is outside the normal operating range wherein the replacement value is derived from the count value of the other of the first and second square wave outputs; and a guidance and navigation system , coupled to the accelerometer, that receives the enhanced output of the accelerometer from the output circuit of the enhancement circuit. an accelerometer having a first vibrating beam providing a first square wave output and a second, complementary vibrating beam providing a second square wave output; an enhancement circuit , coupled to the first and second square wave outputs of the accelerometer, the enhancement circuit comprising: a counter that counts a number of leading edges of pulses in each of the first and second square wave outputs of the accelerometer over a selected period of time; a comparator , responsive to the counter, that determines when the count in the selected period of time for either of the first and second square wave outputs falls outside a normal operating range of values; and an output circuit , responsive to the comparator, that is adapted to replace the count value of one of the first and second square wave outputs with a value in the normal operating range when the comparator determines that the count value for the one of the first and second square wave output is outside the normal operating range wherein the replacement value is derived from the count value of the other of the first and second square wave outputs; and a counter that counts a number of leading edges of pulses in each of the first and second square wave outputs of the accelerometer over a selected period of time; a comparator , responsive to the counter, that determines when the count in the selected period of time for either of the first and second square wave outputs falls outside a normal operating range of values; and an output circuit , responsive to the comparator, that is adapted to replace the count value of one of the first and second square wave outputs with a value in the normal operating range when the comparator determines that the count value for the one of the first and second square wave output is outside the normal operating range wherein the replacement value is derived from the count value of the other of the first and second square wave outputs; and a guidance and navigation system , coupled to the accelerometer, that receives the enhanced output of the accelerometer from the output circuit of the enhancement circuit. <EOS>