New Hampshire-based RadioStack is looking to launch a different kind of amateur radio gear: the Maverick-603 is powered by free and open-source silicon, built using the Efabless platform in a SkyWater factory.
“Maverick-603 is the first affordable FT8 receiver board built around an RF receiver chip designed using fully open source tools and manufacturing,” explain its creators. “It is capable of acquiring FT8 signals between 7MHz and 70MHz. With this frequency range, you will be able to receive signals from around the world with high accuracy. Using our Low Noise Amplifier (LNA) will also give on-chip the ability to amplify very low intensity signals, which is necessary for an effective FT8 receiver.”
The Maverick-603 is an SDR with a difference: its tuner is a completely open chip, built using open source tools. (📷: RadioStack)
Created by Joe Taylor and Steve Franke and released in 2017, FT8 is a digital radio mode based on frequency shift keying and designed to be decodable even with extremely weak signals. The Maverick-603 is specifically suited for this mode, operating as a tunable radio receiver with a control system running on a standard Microchip ATmega1608 microcontroller.
It’s the other chip on the board that’s most interesting, though: the radio receiver itself is a custom design created by RadioStack using only open-source silicon design tools, put on silicon in a factory. of SkyWater Technologies using the company. the SKY130A open source production design kit (PDK) and the Efabless platform. While it’s not the first open-source chip to hit production, thanks to the Google-funded Open MPW program, it’s one of the most practical: a fully functional FT8 receiver.
The radio receiver chips should be built on SkyWater’s PDK SKY130A. (📷: Google)
“It is difficult for open source practices to thrive in the chip design industry, but Maverick-603 demonstrates that open source chip design can produce products that match or exceed their closed source counterparts,” says RadioStack. . “With this project, we aim to generate interest and support, both for amateur radio and for open source chip design.”
FT8 receiver chip design is available on GitHub under the Apache 2.0 permissive license, with more information available on the Efabless project page; fully functional receiver boards, which include the microcontroller and provide an SPI bus for control from an external device in addition to USB support, must be pre-sold via a Crowd Supply crowdfunding campaign in the near future.