AC to DC conversion circuit

1. A half-wave rectifier circuit, comprising:

an input port for receiving an incoming AC signal;

an output port for outputting a half-wave rectified signal;

a operational amplifier including inverting and non-inverting input terminals and an output terminal, said non-inverting input terminal and a negative polarity power supply input of said operational amplifier being coupled directly to a ground reference and said inverting input terminal being coupled to a first resistor;

a negative feedback loop including a second resistor coupled between a first node and a second node, the first node coupling said output terminal and said output port and the second node coupling said inverting input terminal and said second resistor; and

a capacitor coupled to the input port and in series with said first resistor wherein said half-wave rectifier circuit operates without a diode.

2. The half-wave rectifier of claim 1 , wherein the incoming AC signal is amplified by the second resistor divided by the first resistor.

3. The half-wave rectifier of claim 1 , wherein the operational amplifier is a dual preamplifier.

4. The half-wave rectifier of claim 1 , wherein low-level signals below the conduction level of a diode can pass through the half-wave rectifier.

5. The half-wave rectifier of claim 3 , wherein the dual preamplifier output terminal on a negative swing clips-out each incoming AC signal, with the remaining signal half-wave rectified so that an average DC value corresponding to ½ the average AC value is outputted.

6. The half-wave rectifier of claim 4 , wherein signals below 0.75 volts can pass through the half-wave rectifier.

7. A wireless two-way voice (VOX) and keypad device including a half-wave rectifier circuit, comprising:

an input port for receiving an incoming AC signal;

an output port for outputting a half-wave rectified signal;

a operational amplifier including inverting and non-inverting input terminals and a output terminal, said non-inverting input terminal and a negative polarity power supply input of said operational amplifier being coupled directly to a ground reference and said inverting input terminal being coupled to a first resistor;

a negative feedback loop including a second resistor coupled between a first node and a second node, the first node coupling said output terminal and said output port and the second node coupling said inverting input terminal and said second resistor; and

a capacitor coupled to the input port and in series with said first resistor wherein the wireless two-way (VOX) and keypad device operates without a diode.

8. The half-wave rectifier of claim 7 , wherein the incoming AC signal is amplified by the second resistor divided by the first resistor.

9. The device of claim 7 , wherein the operational amplifier is a dual preamplifier.

10. The half-wave rectifier of claim 7 , wherein low-level signals below the conduction level of a diode can pass through the half-wave rectifier.

11. The half-wave rectifier of claim 9 , wherein the dual preamplifier output terminal on a negative swing clips-out each incoming AC signal, with the remaining signal half-wave rectified so that an average DC vale corresponding to ½ the average AC value is outputted.

12. The half-wave rectifier of claim 10 wherein signals below 0.75 volts can pass through the half-wave rectifier.