How do I build a phantom power supply?
The circuit below is a basic 12 volt phantom power supply that can be constructed in several hours by an electronics hobbyist. It consists of parts commonly available at Radio Shack or Digikey.
This circuit will provide 5 milliamps of phantom power and is designed to operate an electret condenser microphone. It cannot power any condenser microphone that requires 48 volt phantom power. If you are unsure about what your microphone's phantom power requirements, check the microphone's technical literature or contact the manufacturer.
R1, R2 = 750Ω, 1/4 watt, 1%
R3, R4, R5 = 510Ω, 1/4 watt, 5%
R6, R7 = 1MΩ, 1/4 watt, 5%
C1 - C5 = 47μF, 35 vdc
J1 = 3 pin female XLR connector
J2 = 3 pin male XLR connector
T1 = ac to dc power adapter, 12 vdc output, 50 mA or greater
Important: The circuit above must be in a metal (shielded) enclosure.