Speedometer/odometer apparatus

A speedometer/odometer apparatus for indicating speed and milage of a vehicle, comprising:

• a sensor means for converting a mechanical motion of an engine of the vehicle into an electronic signal;
• an amplifier means for amplifying said electronic signal;
• a binary-counting frequency divider means coupled to said amplifier means for dividing of said amplified electronic signal;
• a demultiplexer means coupled to said frequency divider means for demultiplexing said electronic signal;
• a differential circuit, coupled to said demultiplexer means and receiving said electronic signal, for triggering;
• a monostable circuit triggered by said differential circuit to output stable voltage pulses;
• a crystal oscillator for outputting a high frequency signal;
• a combiner coupled to said crystal oscillator and said monostable circuit for combining the high frequency signal generated by said crystal oscillator with the stable voltage pulses generated by said monostable circuit into a combined signal and dividing the combined signal into regular pulses;
• a frequency divider circuit for dividing a frequency of said regular pulses binarily and outputting a first output signal and a second output signal;
• an air cord meter driver circuit for receiving said first signal of said frequency divider circuit to drive an indicator of said speedometer and indicate the speed;
• and
• a counter driver circuit for receiving said second output signal of said frequency divider circuit to calculate and indicate the mileage.