Dual Rail AC Power Supply PCB (LM317 / LM337)

This power supply PCB provides an adjustable and stable dual-rail power solution for Eurorack systems and other audio electronics projects. It is designed to operate from an external AC transformer, generating regulated bipolar supply rails suitable for analog audio circuits.

The design combines a switching regulator stage with linear regulation to achieve efficient operation and reliable performance. Clear labeling and a practical layout make the PCB suitable for DIY builders with basic electronics experience.

In addition to Eurorack applications, the board can be used to power a wide range of audio and electronic projects that require a dependable dual-rail supply.

Key features

• Designed for use with external AC transformer input
• Adjustable Dual-rail regulated power supply
• Switching + linear regulation topology
• Suitable for Eurorack and general audio projects
• Compact PCB for DIY and custom builds
• Clearly labeled connections for assembly

Safety Disclaimer

This power supply PCB is intended for DIY and educational use by users with basic electronics knowledge. It is designed to operate from an external AC transformer only. Incorrect wiring, improper transformer selection, or use outside the specified ratings may result in damage to the PCB, connected equipment, or personal injury.

Always disconnect power before working on the circuit. The user assumes full responsibility for correct installation and safe operation.

Important Recommendations

• Use only an external AC transformer within the specified voltage and current range.
• Do not connect DC power sources directly to the AC input.
• Ensure correct polarity and secure connections before powering the board.
• Verify output voltages before connecting sensitive audio or Eurorack modules.
• Provide adequate ventilation and mounting clearance during operation.
• This PCB is not a finished consumer product.