I know little about this but I think the device is called HackRF and costs about $350. It can act as a receiver and sender.
If you want to tinker with radio stuff for less money, you could start with a receiver only and try RTL-SDR. RTL-SDR is software-defined radio (=SDR) based on a particular RealTek (=RTL) chip. Suitable devices are as cheap as the right DVB-T USB receiver (check the list in the reddit-wiki for what might work and what might not) but there are more optimized devices for approximately $40 (un)available (because supply chain) - have a look at the rtl-sdr shop for those.
If you want to tinker with radio stuff for less money, you could start with a receiver only and try RTL-SDR. RTL-SDR is software-defined radio (=SDR) based on a particular RealTek (=RTL) chip. Suitable devices are as cheap as the right DVB-T USB receiver (check the list in the reddit-wiki for what might work and what might not) but there are more optimized devices for approximately $40 (un)available (because supply chain) - have a look at the rtl-sdr shop for those.
https://www.rtl-sdr.com/
https://www.reddit.com/r/RTLSDR/