Tagged: raspberry pi pico

Pi Pico Rx: A Breadboard Software Defined Radio Based on the RP2040 Raspberry Pi Pico

Over on hackster.io we've seen a story about how maker Jon Dawson designed a self-contained software-defined radio based on the Raspberry Pi Pico that can receive 0 - 30 MHz, with up to 250 kHz of bandwidth. The Raspberry Pi Pico is a microcontroller board based on the Raspberry Pi Foundation's own RP2040 chip.

The Pi Pico Rx's front end consists of a Tayloe Quadrature Sampling Detector (QSD) mixer which makes use of the PIO (Programmable Input/Output) feature on the RP2040. The circuit also has an encoder knob for tuning and a small OLED screen.

Jon had originally created the Pi Pico Rx on a custom PCB, however, his latest work brings the cost down by showing that it can just as easily be implemented on a breadboard with through-hole components.

The full writeup can be found on Jon's blog "101 Things", as can the open source firmware. He has also uploaded a YouTube video explaining and demonstrating the project which we've embedded below.

Software Defined Radio with Pi-Pico

An HF Ham Radio SSB/AM/FM/CW Transmitter made from a Raspberry Pi Pico and not much more

Over on Hackaday we've seen a story about a Raspberry Pi Pico based software defined radio transmitter that is capable of transmitting SSB, AM, FM and CW anywhere between 0.5 - 30 MHz.

The design generates an oscillator signal using the Pico's Programmable IO. For AM/SSB it uses the PWM output pins to generate an RF envelope which gets mixed together with the oscillator using an analog multiplexor. A small microphone is also connected to the Pico for voice transmissions. The designer notes that the output power is far too low to be used on the air, but adding an output amplifier would help.

The software is all open source and provided on GitHub, and more information about the design can be found on the designer's '101things' website.

The Raspberry Pi Pico is a low cost microcontroller board, and we note it cannot run Linux like standard Raspberry Pi boards. This means that software like RpiTX cannot be used.

Build a Ham Transmitter with a Raspberry Pi Pico

PiccoloSDR: A Simple SDR From a Raspberry Pi Pico

The Raspberry Pi Pico is a $4 microcontroller board. Recently radio amateur Luigi Cruz discovered that the ADC on the Pico could be used as a simple direct sampling software defined radio, with a bandwidth of 250 kHz. The idea is that the ADC data is made available to a PC connected to it's USB port via emulated TCP/IP protocol. On the PC side, GNU Radio is then used to process the received ADC data, turning it into an SDR.

Applications of a direct sampling SDR with only 250 kHz are limited, as it's only possible to receive up to the LF band, and there are not many signals that low in frequency. However, it is an interesting project that can be used to demonstrate a simple SDR. If you're interested in trying it out, the code is available over on GitHub.

PiccoloSDR Project - Using the Raspberry Pi Pico RP2040 as an SDR - First Test with GNU Radio.

[Also seen on Hackaday]