Al lot of ham's have discovered the Quansheng UV-K5 (8) radio as it offered the amazing possibility to hack te firmware and by doing so adding features like SSB reception.
Normally only high priced versions of Kenwood, Icom or Yaesu offer such possibilities, but here for a few 10euro notes you get similar possibilitities.

Of course this hacking has some disadvantages as the hardware is not optimized for these kind of hacked-features.
And Quansheng has been following closely what happend to their radios and has also been listening very well to its customerbase

One of the more popular items on my website here are the Arduino based CTCSS projects

One disadvantage of these projects is that a traditional ATMega328p microcontroler is rather big and in the way it is used in the projects needs a 16MHz x-tal to function. This results in a circuit that is often to big and also a more expensive solutions that one would hope for. For these reasons I've created a new version of this project based on the popular "ATTiny" microcontrollers.

The Raspberry Pi Pico was the first Microcontroller build by the Raspberry Pi foundation, and you know what? You can use it as an SDR !

The idea is to use the ADC of the Pico to sample and forward the data via emulated TCP/IP to a regular PC where you can run your favorite SDR software

More information on this project can be found on github at this page:

https://github.com/luigifcruz/pico-stuff/tree/main/apps/piccolosdr