Retrocution's AV-USB Adds Three USB Ports, Analog Audio and Video to the Raspberry Pi Zero 2 W

Pseudonymous maker "Retrocution" has launched an add-on for the Raspberry Pi Zero 2 W single-board computer that makes full use of the test points on its underside to add three full-size USB 2.0 ports plus analog audio and video outputs: the AV-USB.

"While I was looking at the bottom of the [Raspberry] Pi Zero 2 W and figuring out the best way to wire a composite video cable into [its] little test pad," Retrocution explains of the board's origin, "I realized I could design a sandwich board that uses pogo pins to make all the connections. I had seen other products use this approach before, and it seemed like the cleanest way to keep everything compact without having to solder."

The Raspberry Pi Zero 2 W is a surprisingly capable, low-cost, small-footprint single-board computer — but it comes with a range of trade-offs to get there, both in relation to its bigger brethren and to rival SBC designs. It has only one USB port, and it's a micro-USB On-The-Go (OTG) port requiring an adapter for use with full-size USB Type-A devices, and it lacks a connector for analog audio and video. The same was true of its predecessor, but that at least had an unpopulated through-hole header for composite video; the Raspberry Pi 2 W, however, removed this entirely.

While the header may have been moved to save board space for other things, though, the capability is still there — and still accessible, using plated test pads on the underside of the board. Retrocution's AV-USB "sandwich" board takes advantage of both these and the typically-unpopulated 40-pin general-purpose input/output (GPIO) header to provide three full-size USB Type-A ports and a 3.5mm AV jack with stereo analog audio, generated by a Texas Instruments PCM5102 sound chip, and composite video.

As the board uses pogo-pins, there's no soldering: the AV-USB simply mounts underneath the Raspberry Pi Zero 2 W and screws into place, and if you decide to repurpose it unscrews cleanly leaving both boards reusable.

More information is available on Retrocution's blog, along with a link to purchase from a "small number" of boards currently produced at $19.99.