Amateur Radio

Yes, there are a couple of options, rfbitbanger (currently on the second batch of crowfounding) and adx (arduino digital transceiver).

Digital modes are usually based on an SSB transceiver, unless you are talking about something with specialized hardware radios like LORA. (In the end, all radio is analog!) So, consider SSB radios even if you will only pass digital signals through them

Another option is the truSDX (https://dl2man.de). You can get software for the PC that will route audio over CAT so you can do it with just a USB cable. The FT8CN Android app also supports it natively.

I just posted this in another thread.

I’m just staring to build a T41 SDR QRP Transceiver

SDR = Software Defined Radio, 
QRP is the Q code for reduce power, QRP radios are meant for low power operations.

Not sure if you want to go down the kit route but it will teach you a bit about RF (Radio Frequency) theory and practical electronics (If you don’t already know). It’s also very modular and there are other options for the RF amplifier section so it does not have to be QRP, there is a 20W and 100W board available as well.

Be warned that this kit will take a lot of time, reading, careful soldering of tiny SMD (Surface mount devices) components, etc. There is a good book about the kit, the theory, programming the Tensy (the microcontroller heart of the t41), etc.

http://4sqrp.com/T41main.php

https://www.amazon.com/Software-Defined-Radio-Transceiver-Construction/dp/B09WYP1ST8

Note: I know most in this community will know the acronyms, I spell them out for others that may happen by

There is also the QMX transceiver from QRP Labs. It can do CW as well as single carrier FSK digital modes.

I would suggest getting a radio that can do SSB. There are a lot of digital modes that won't work with radios like the QDX or QMX.