AIOC: The Ham Radio All-In-One Cable For Audio And APRS

The Ham Radio All-in-one cable (AIOC) is a small PCB attachment for a popular series of radio transceivers which adds a USB-attached audio interface and virtual TTY port for programming and the push-to-talk function. The STM32F373 microcontroller (which, sadly is still hard to find in the usual channels) is a perfect fit for this application, with all the needed hardware resources.

With USB-C connectivity, the AIOC enumerates as a sound card as well as a virtual serial device, so interfacing to practically any host computer should be plug-and-play. Connection to the radio uses 12mm separation 3.5mm and 2.5mm TRS connectors, so is compatible with at least the Baofeng UV-5R but likely many other cheap transceivers that have the same physical setup.

Instructions are provided to use the AIOC with Dire Wolf for easy access to APRS applications, which makes a nice out-of-the-box demo to get you going. APRS is not all about tracking things though since other applications can sit atop the APRS/AX.25 network, for example, HROT: the ham radio of things.

We’ve seen quite a few Baofeng (and related products) hacks, like this sketchy pile of wires allowing one to experiment with the guts of the radio for APRS. Of course, such cheap radio transceivers cut so many engineering corners that there are movements to ban their sale, so maybe a new batch of better radios from our friends in the East is on the horizon?

Thanks to [Hspil] for the tip!

STM32 And FPGAs In A Tiny Package

Slowly, very slowly, the time when we don’t subject embedded beginners to AVRs and PICs is coming. At a glacial pace, FPGA development platforms are becoming ever more capable and less expensive. [Eric Brombaugh] has been playing around with both ARMs and FPGAs for a while now and decided to combine these two loves into a single board that’s capable of a lot.

This board is fittingly called an STM32F303 + ice5 development board, and does exactly what it says on the tin. There’s an STM32F303 on board providing a 32-bit CPU running at 72 MHz, 48 kB of SRAM, a quarter meg of Flash, and enough peripherals to keep anyone happy. The FPGA side of this board is a Lattice iCE5 with about 3k Look Up Tables (LUTs), and one time programmable non-volatile config memory.

The connections between the ARM and FPGA include a dedicated SPI port, and enough GPIOs to implement full-duplex I2S and a USART. Like all good projects, [Eric] has shared all the files, schematics, and BOMs required to make this board your very own reality, and has provided a few links to the development toolchains. While the FPGA is from Lattice’s ice40 family, it’s not supported by the Open Source Project Icestorm toolchain. Still, it’s a very capable board for ARM and FPGA development.