WavelensWhat the journal is telling you: a field guide to the bridge's log
sudo journalctl -u wavelens-bridge -f on the Pi, or just scroll to the bottom of the Alerts tab in the app: the same lines. They come from the bridge itself (bridge:), from the tools it runs (rtl_tcp:, dsd-fme:, rtl_power:, rtl_433:) and from the journal's own timestamps.
Normal
| Line | Meaning |
|---|---|
bridge: hardware: 2 RTL-SDR (00001090: sensors, 00000978: listen) · no HackRF | The USB inventory at connect. Printed whenever it changes. |
bridge: control-channel hunt: 800 MHz (sweep, 3 passes): 18 steady — … | Steady carriers found; the scanner is about to rank and try them. |
dsd-fme: Sync: +P25p1 NAC/CC: 800; TSBK | Locked on a control channel. TSBK = control traffic. |
dsd-fme: Sync: +P25p1 … LDU1 / HDU | Voice frames: a call is playing. |
bridge: listen: 856.9625 MHz quiet for 5 s; next system … | Scanner rotation. HOLD stops it. |
rtl_tcp: Signal caught, exiting! / dsd-fme: Exiting. | A retune. The tools are restarted per frequency; this is every hop. |
bridge: hackrf_sweep paused while digital voice is decoding | By design: USB and CPU for the decoder. |
dsd-fme: Encrypted Group Voice Channel Grant | An encrypted call the decoder correctly didn't tune. |
Problems, and the fix
| Line | What's wrong |
|---|---|
rtl_fm: usb_claim_interface error -6 | Another process has the dongle — usually the sweep that hadn't finished exiting, or dump1090 on the wrong stick. The bridge now frees the dongle itself (TERM, then KILL, then a USB reset via sysfs). If it persists, pgrep -a rtl_ and look for a stray. |
dsd-fme: Base Frequency Not Found - Iden [0], repeating | dsd-fme is on a voice channel, not the control channel, waiting for a channel map. The bridge treats P25p1-with-voice-and-no-TSBK as a voice channel and moves on. If you tuned it by hand, pick a different carrier. |
rtl_power: [R82XX] PLL not locked! | Tuned outside the tuner's range (below 24 MHz, or a direct-sampling attempt). Harmless once; constant means a bad range in --rtl-power. |
bridge: rtlpower: 9 bands rose together; … receiver overload | A very strong local transmitter (or you drove past a tower). The bridge discards the pass. Frequent at one spot → lower the sweep gain. |
bridge: rtl_433 exited 1 s after start (no sensor dongle?) | The sensor dongle isn't there or is held. The bridge carries on without TPMS; check the hardware line and the power supply. |
hackrf_sweep: hackrf_open() failed: HackRF not found (-5) | Unplugged, or sitting in the PortaPack menu. The bridge now waits for it quietly; if you removed the HackRF on purpose, nothing to do. |
dsd-fme: Failed to connect to rtl_tcp server | Used to be every tune (dsd-fme started before rtl_tcp was listening). Now the bridge waits for rtl_tcp's "listening…" first; seeing it means rtl_tcp itself failed to open the dongle — look just above for why. |
No audio, journal fine, trunked call: TG … · muted | Not a fault: the PUBLIC SAFETY/FIRE/EMS filter or a TG lock muted that call. Tap the category again to hear everything. |
When you send us a log
The Alerts tab's journal is enough in nearly every case. Long-press it to copy, or on the Pi: sudo journalctl -u wavelens-bridge -n 300 --no-pager > bridge.log. It contains frequencies and talkgroup numbers and the dongle serials — nothing about you. Email it with what you expected to hear.
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