The project aims to:

• Provide a clean and stable 13.8 V for radio equipment. 

• Utilize various unsuitable power supplies, such as PC or server power supplies, without modification.

• Enable portable operations and serve as an emergency power source using tool batteries.

Key Components and Construction:

The main components are a DC 8-40 V to 13.8 V 30 A Boost-Buck converter and EMI filters.

The total cost for the main parts was approximately $70 USD.

The construction involves:

Input and output power meters to monitor voltage and consumption.

RFI/EMI filtering units for both input and output to ensure clean power.

XT60 connectors for input sources above 13.8 V.

Powerpole connectors for 13.8 V output.

Silicone 12-gauge wires for high current applications.

Independent switches for input and output power.

The entire assembly is housed in a metal box to contain RFI.

Testing and Performance:

Tested extensively with various power sources and loads:

• Variable power supply testing from 8 V to 28.75 V, consistently yielding 13.75 V output.

• High current testing with a 12 V AGM battery, showing the device maintains 13.75 V even as the battery voltage drops.

Tested successfully providing stable 13.8 V output with:

• 40 V hoverboard lithium-ion battery

• 12 V Milwaukee lithium-ion battery

• 18 V Makita lithium-ion battery

• 20 V DeWALT lithium-ion battery

Tested with a Gigabyte 750 W PC power supply, demonstrating its ability to convert 12 V to 13.8 V without modifying the power supply

Real-world testing with a Yaesu FT-857D radio at 75 W and 100 W, showing the module's performance with different batteries. 

The module can shut down at around 25 amps with less than 12 V, but performs well with higher voltage batteries like the 40 V hoverboard battery and 20 V Makita battery at 100 W RF output.