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Run GopherTrunk 24/7 on a Raspberry Pi
A Raspberry Pi 5 plus a ~$35 RTL-SDR is the ideal always-on GopherTrunk scanner — low power, silent, headless, and reachable from any browser on your network through GopherTrunk’s built-in web console. Leave it next to the antenna and it logs every call, day and night, while you check in from your phone or laptop.
Key takeaways Host: Raspberry Pi 5, 8GB (~$80). Receiver: any good RTL-SDR (~$35). Connect the dongle through an active USB extension (~$15) — better power, moves the warm dongle off the board. Control it from any browser via the web console — no monitor on the Pi. Use a solid power supply — the top cause of 24/7 dropouts is under-powering the Pi.
Why a Pi for always-on scanning
A desktop PC works, but it is overkill for a job that runs forever. A Raspberry Pi is the natural home for a permanent GopherTrunk decoder because it is:
- Low power and silent. A Pi 5 sips a few watts — cheap to leave on 24/7, with no fan noise if you cool it passively.
- Headless by design. GopherTrunk is a single Go binary; it runs with no desktop and is driven entirely through its web console, so the Pi needs no monitor, keyboard, or mouse once configured.
- Small enough to live at the antenna. Mount it in a closet, attic, or by a window right where the feedline comes in, minimizing coax loss to the dongle.
- Plenty capable. A Pi 5’s cores decode one or more P25 / DMR / NXDN control channels plus voice with headroom to spare.
The parts list
| Part | Why | Pick | Approx $ |
|---|---|---|---|
| Raspberry Pi 5 (8GB) | The always-on host | Pi 5 8GB | ~$80 |
| SDR dongle | Receives the radio | RTL-SDR Blog V4 / NESDR | ~$35–40 |
| Active USB extension | Stable power, moves the warm dongle away | Shielded active repeater cable | ~$15 |
| Antenna + adapter | Actually hears signals | Dipole / discone | ~$25–40 |
| Official power supply + cooling | Reliability | Official USB-C PSU, active cooler | ~$20 |
Full shopping context is in the what-you-need checklist and the dongle rundown in best SDR for GopherTrunk.
Power and USB — the reliability part
Almost every “my Pi scanner randomly drops out” story comes down to power and USB, not software. Two rules:
Feed the Pi properly. Use the official USB-C supply. A Pi 5 driving a power-hungry, warm-running RTL-SDR on a marginal charger will brown out and throw USB errors. Adequate, stable power is the single biggest reliability factor.
An active (powered) USB extension cable does double duty: it provides a cleaner power path to the dongle and moves the hot dongle away from the Pi’s board and away from RF-noisy USB 3 ports. If you run several dongles, use a powered USB hub instead so the Pi is not asked to source all that current itself — see the multi-dongle setup guide.
Remote access through the web console
The payoff of a headless Pi is GopherTrunk’s web console. Once the Pi is running, point any browser on your network at its address and you get live spectrum, per-call logs with timestamps, and full control — no screen attached to the Pi at all. Tune it from the couch, check overnight logs from work, or watch calls scroll in on your phone. This is what turns a Pi in a closet into a genuinely convenient scanner.
Setup in brief
- Flash 64-bit Raspberry Pi OS and boot the Pi headless (enable SSH, join Wi-Fi or Ethernet).
- Download the GopherTrunk binary for ARM64 and follow the hardware setup guide.
- Plug the RTL-SDR in through the active extension; attach the antenna.
- Enter your system’s control channel (look it up on RadioReference), start GopherTrunk, and open the web console from another device.
- Set it to start on boot so it comes back after any power blip.
Bottom line
For a scanner that just runs, a Raspberry Pi 5 + a RTL-SDR + an active USB extension is the sweet spot: cheap, silent, always on, and controlled entirely through GopherTrunk’s web console. Get the power supply right, place it near the antenna, and you have a purpose-built digital scanner logging every call around the clock. Start from the hardware guide and the what-you-need checklist.
Frequently asked questions
Can a Raspberry Pi run GopherTrunk?
Yes. GopherTrunk runs on 64-bit Raspberry Pi OS, and a Raspberry Pi 5 (8GB) has ample CPU to decode one or more control channels plus voice around the clock. A single Go binary runs headless with no desktop, so the Pi can sit next to the antenna and be reached over your network.
Which Raspberry Pi should I use?
A Raspberry Pi 5 with 8GB of RAM is the recommended pick — its faster cores comfortably handle P25/DMR/NXDN decoding and even wideband channelizing. A Pi 4 works for a single site. Give either a good power supply and, ideally, active cooling for 24/7 duty.
How do I control a headless Pi scanner?
GopherTrunk has a built-in web console. Point any browser on your network at the Pi’s address and you get live spectrum, call logs, and controls — no monitor or keyboard needed on the Pi itself. That is what makes an always-on Pi so convenient.
Do I need a powered USB hub or extension for the Pi?
Often yes. RTL-SDR dongles draw meaningful current and run warm, and plugging one directly into the Pi can cause brownouts or put the hot dongle right against the board. An active (powered) USB extension cable moves the dongle away and stabilizes power.
Will a Pi keep up with decoding?
For one or two control channels plus voice, easily. A Pi 5 can even channelize several signals from one wideband capture. If you drive a large multi-dongle pool you may want a more powerful host, but for a typical single-site setup a Pi is plenty.
Does the Pi need a good power supply?
Yes — use the official USB-C supply. Under-powering a Pi 5 while also feeding a power-hungry SDR is the number-one cause of random dropouts and USB errors. Adequate, stable power is the single most important reliability factor for a 24/7 build.