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Best SDR for GopherTrunk (2026 Buyer’s Guide)
The best SDR for GopherTrunk is the cheapest one that cleanly hears your local control channel — and for most people that’s a ~$35 RTL-SDR. GopherTrunk is free, open-source software that turns a USB software-defined radio into a P25/DMR/NXDN/TETRA trunking scanner, so the radio is the only thing you buy.
Key takeaways Best overall: RTL-SDR Blog V4 or NooElec NESDR SMArt v5 (~$35–40). Best for tough/busy RF: Airspy R2 (12-bit, wideband). Best for HF too: Airspy HF+ Discovery. Overkill but versatile: HackRF One. You only buy the radio — the software is free and runs on a PC or Raspberry Pi. No SDR decodes AES encryption.
Quick picks
RTL-SDR Blog V4
around $40
The reference dongle: 1 ppm TCXO, built-in HF upconverter, SMA, switchable bias tee. Plenty for P25/DMR/NXDN trunk-tracking.
V4 on Amazon →NooElec NESDR SMArt v5
around $35
0.5 ppm TCXO, aluminium case, R820T2/R860. The mainstream "just buy this" RTL-SDR — always in stock.
NESDR on Amazon →Airspy R2 / Mini
around $110–170
12-bit ADC and up to ~10 MHz capture — decodes weak and congested channels and channelizes multiple control channels at once.
Airspy on Amazon →Airspy HF+ Discovery
around $170
Exceptional HF/low-VHF dynamic range. The pick if you also want shortwave, ham HF, or utility monitoring.
HF+ on Amazon →Full comparison
| SDR | ADC | Range | Bandwidth | Best for | Approx price |
|---|---|---|---|---|---|
| RTL-SDR Blog V4 | 8-bit | ~500 kHz–1.77 GHz | ~2.4 MHz | The default; HF via upconverter | ~$40 |
| NESDR SMArt v5 | 8-bit | ~100 kHz–1.75 GHz | ~2.4 MHz | Value, always in stock | ~$35 |
| NESDR SMArTee v2 | 8-bit | VHF/UHF | ~2.4 MHz | Powering an LNA (bias tee) | ~$40 |
| Airspy Mini | 12-bit | ~24 MHz–1.8 GHz | ~6 MHz | Better decode, portable | ~$110 |
| Airspy R2 | 12-bit | ~24 MHz–1.8 GHz | ~10 MHz | Wideband multi-site channelizing | ~$170 |
| Airspy HF+ Discovery | high-DR | HF + 60–260 MHz | ~0.66 MHz | HF / low-VHF | ~$170 |
| HackRF One | 8-bit | 1 MHz–6 GHz | ~20 MHz | Range + transmit (overkill for scanning) | ~$150 |
Read your system first. Look up your target on RadioReference: one RTL-SDR follows one control channel cleanly. If a system’s sites or control channels are spread across a band, plan for a wideband Airspy or a multi-dongle pool.
How to choose
- Just starting / on a budget? RTL-SDR Blog V4 or NESDR SMArt v5. One dongle follows most local trunked systems.
- Weak signal, congested band, or lots of intermod? An Airspy’s 12-bit front end pulls voice out of conditions that push an 8-bit RTL-SDR into overload.
- Multiple sites / wideband monitoring? An Airspy R2 channelizes several control channels from one capture, or run a pool of RTL-SDRs.
- Want HF (shortwave, ham, utility) too? Airspy HF+ Discovery, or a V4’s built-in upconverter. See best HF SDR.
- Already own a HackRF or need 6 GHz / transmit? GopherTrunk will use it as a receiver — just know it’s more than scanning needs.
Don’t forget the rest of the kit
An SDR alone won’t scan. You also need a computer (any PC, or a Raspberry Pi for 24/7), a decent antenna, and usually an SMA adapter or cable. Our complete what-you-need checklist walks through every piece. Then download GopherTrunk and follow the hardware setup guide.
SDR vs a dedicated scanner
A dedicated police scanner is turnkey and portable; an SDR + GopherTrunk is free (after the dongle), records and timestamps every call, follows unlimited talkgroups, and streams to a web console. The honest head-to-head is in police scanner vs GopherTrunk.
Bottom line
Start with a RTL-SDR Blog V4 or NESDR SMArt v5 — they run GopherTrunk beautifully for about $35. Move up to an Airspy only when your RF is genuinely tough or you want wideband multi-site capture. Whatever you pick, no SDR decodes encryption, and the software is free — so the cheapest capable dongle is usually the right answer.
Frequently asked questions
What is the best SDR for GopherTrunk?
For most people, an RTL-SDR Blog V4 or a NooElec NESDR SMArt v5 (around $35–40) is the best SDR for GopherTrunk — cheap, well-shielded, and more than enough to follow P25, DMR, and NXDN trunked systems. Step up to an Airspy R2 for tough or busy RF, or an Airspy HF+ Discovery if you also want HF.
Do I need an expensive SDR to run GopherTrunk?
No. GopherTrunk is built to run on a ~$30 RTL-SDR dongle. A better SDR (Airspy) helps in congested band conditions or when you channelize many signals from one wideband capture, but a good RTL-SDR decodes the same P25/DMR/NXDN voice.
Can one SDR follow a whole trunked system?
Yes — one RTL-SDR can follow a single trunked site by tracking its control channel. For a multi-site system or control channels spread far apart, GopherTrunk can drive a pool of dongles, or use a wideband Airspy to channelize several at once.
Is a HackRF One good for GopherTrunk?
It works but is overkill for scanning: its 8-bit ADC has less dynamic range than an Airspy, and its transmit and 6 GHz reach are wasted on receive-only VHF/UHF decoding. Buy a HackRF only if you also need those capabilities for other projects.
Can an SDR decode encrypted police?
No. No SDR — and no scanner — can decode AES-encrypted talkgroups. GopherTrunk decodes clear and even scrambled traffic but never keyed encryption. Choose hardware based on the systems still in the clear.
What else do I need besides the SDR?
A computer (any PC, or a Raspberry Pi for 24/7), a decent antenna, and usually an SMA adapter or two. See our complete what-you-need checklist for the full list.