What is software-defined radio (SDR)?: The basics for critical communications users - Barrett Communications
Getting Started With Software Defined Radio (SDR) - Make:
Nooelec - Nooelec NESDR SMArt HF Bundle: 100kHz-1.7GHz Software Defined Radio Set for HF/UHF/VHF including RTL-SDR, Assembled Ham It Up Upconverter, Balun, Adapters - SDR Receivers - Software Defined Radio
Software Defined Radio | Q R P e r
RX-888 MK2 HF/VHF/UHF Software Defined Radio | LTC2208 16Bit ADC with Direct Sampling | DDC DUC SDR | ELEKITSORPARTS
Sdr Dsp Receiver | Radio Receiver | Smart Remote Control - 1.10c 3.5 50khz-2ghz - Aliexpress
4.3" Software Defined Radio SDR Radio Receiver DSP CW/AM/SSB/FM/WFM 100k-149MHz | eBay
Amazon.com: Xiegu X6100 HF Transceiver, 10W Full Mode SDR Radio Supports Bluetooth with 3.6" LCD Screen : Electronics
Amazon.com: 1.10b Malachite SDR Radio Receiver 50KHz-2GHz, 3.5" Malachite DSP SDR Receiver,AM/LSB/NFM/WFM Full Band Radio,Aluminum Alloy ,Two Speaker(Upgrade) (1.10b) : Electronics