Active Humbucker Preamp

Active Humbucker Preamp is a tiny preamp circuit to turn a passive Guitar Humbucker Pickup into an Active "Powered" Pickup!

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The wire cable coming directly from the Humbucker pickup (Shield, North Start, North Finish, South Start, South Finish), are connected directly to this circuit board, via a Screw-Terminal connector.

A standard 9volt battery is also soldered directly to the circuit board, via a battery "snap" connector.

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The single input opamp I chose is a tiny OPA1677DBVT which is a surface-mount device SOT23-5.

Resistors and capacitors are equally small 0805's, to keep this circuit board small.

You can use double-sided tape to stick it to the 9volt battery with room to spare.

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The Guitar Jack must be changed to a 1/4" Stereo Jack, as it will also act as a power switch- when a guitar cable is inserted, one internal contact will be grounded providing the ground for the circuit board power supply. When the guitar cable is removed, it breaks the ground, turning off power to the circuit board.

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The single opamp circuit is a low-gain, which is set by Resistors R5 and R7.

Opposing Positive and Negative inputs of the Humbucker Pickup go into IC1 opamp on Pins 3 & 4.

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Output of the circuit board, labeled "Tip", is then connected to the rest of the Guitar Circuitry- Volume Controls, Tone Controls, Pickup Selector Switch, etc.

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Circuit has not been verified.