For more than a decade, a roughly 30 dollar USB dongle has been the way most people start with software-defined radio. Engineer Patrick Quirk now argues in a detailed post that this era is ending, because the tuner chips inside the cheapest SDRs are going out of production. He found out while designing a Raspberry Pi CM5 carrier with an SDR on board, when the radio chips it needed could not be bought anywhere.
Which chips are going
The cheap SDR was always a hack of TV hardware. RTL-SDR started as a mass-produced DVB-T TV stick built on the Realtek RTL2832U, until developers found they could read its raw samples. As people stopped buying TV sticks, the chips made for them have been reaching end of life:
- Rafael Micro R828D: used in the RTL-SDR Blog V4. No longer produced. RTL-SDR Blog announced the end of the V4 in May 2026.
- Rafael Micro R828S: used in the V4L replacement, which is a limited run from a stockpile and needs an updated driver.
- Rafael Micro R820T2: used in the RTL-SDR V3 and Airspy R2 and Mini. Regular production ended around 2018, with batches made only for very large orders.
- Mirics MSi2500 and MSi001: used in the SDRplay RSP1 and many clones. Zero stock at JLCPCB and LCSC from February to November 2026, and the Mirics website no longer resolves.
- Maxim MAX2839: used in the HackRF One r9, now obsolete.
What is still being made
Receivers built on chips designed for radio and telecom work are still on sale, at higher prices. RTL-SDR Blog says the V3, now with a Rafael R860 tuner, will remain in stable production. SDRplay's RSP1B and RSPduo are in stock, the Analog Devices ADALM-Pluto is still sold, and the newer HackRF Pro and the LimeSDR family are current. The catch is that these use transceivers that need far more supporting hardware than a TV tuner, and each comes from a single supplier. As the post puts it, an open schematic protects you from a company vanishing, but not from a chip vanishing.
What this means for makers
For buyers, the advice is simple: an RTL-SDR Blog V3 for a cheap all-rounder, a V4L now if you want V4-class performance, and caution with cheap RSP1 and MSI.SDR clones whose chip sources are unknown. For hardware designers, check a part's stock history before committing, and make the radio section swappable. Browse our SDR projects and news for ideas on what you can still build with these receivers.
Image credit: Patrick Quirk / ringmast4r, cropped and resized.
About the author: Aswinth Raj is an electronics engineer and the editor of CircuitDigest, where he has published more than 150 hands-on projects and tutorials across Arduino, PIC, ESP32, Raspberry Pi and EV battery systems. He selects the stories on this page for what engineers and makers can actually learn or build from. Connect on LinkedIn
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