r/RTLSDR • u/No-Coat2826 • 4h ago
r/RTLSDR • u/jasiek83 • 5h ago
Three web ports I've built: rtl_433, multimon-ng and rtl-wmbus
Everything runs in your browser - here's what you can do:
- https://web-rtl-433.jasiek.me/ - pick up various devices running on ISM bands (mostly weather stations)
- https://web-rtl-wmbus.jasiek.me/ - read water/gas/electricity meters
- https://web-rtl-multimon.jasiek.me/ - read POCSAG and FLEX pagers
(obvs, only use them when they're legal to use where you are)
r/RTLSDR • u/No-Coat2826 • 6h ago
A little Bluetooth SDR we going to be making
littlespec.com*we’re
1.7 GHz and above Helicone Elektro L3 reception
Little thing is capable of LRIT reception 😃
r/RTLSDR • u/Budget_Deer6556 • 13h ago
How to Fill the 380 MHz – 404 MHz Gap:
Hi all,
One of my SDR had a hardware limit/gap ranging from 380 to 404 MHz. So, if I use any up- or downconverter, will I be able to cover the missing gap? looking for suggestions from expertise. Thanks in advance.
Using Claude/ChatGPT to control SDRangel
"SDRangel has a step learning curve" - well, now you can ask Claude/ChatGPT to help, with version 8's MCP server.
r/RTLSDR • u/One-Explanation6552 • 1d ago
Puzhi PZSDR P401D / P501D: Pin-compatible phase-coherent 4T4R AD9361 SDR (ZU4EV / ZU5EV)
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Puzhi Electronics has released a pair of pin-compatible 4TX/4RX SDR platforms built around dual AD9361 transceivers and AMD Zynq UltraScale+ MPSoCs.
The P401D and P501D share the same RF section, connectors, PCB layout and software support. Users select the variant based on required FPGA logic and DSP capacity.
Shared Specifications
- RF: Dual AD9361, phase-coherent 4T4R MIMO
- Frequency range: 70 MHz – 6 GHz
- Instantaneous bandwidth: 200 kHz – 56 MHz
- Tx output: up to 22 dBm
- 0.1 ppm 40 MHz VCTCXO, external 10 MHz / PPS sync supported
- SPDT switches rated 9 kHz – 8 GHz
- Processing: 4×A53 u/1.3 GHz + 2×R5 u/533 MHz
- Memory: 2GB DDR4, 8GB eMMC, 256Mb QSPI Flash
- I/O: 40G QSFP, GigE, USB3.0, Mini DP, SSD slot, 40-pin expansion, GPS+Beidou timing
- Power: 12V 3A single supply, all external interfaces ESD protected
- Size: 160 × 150 mm
Variant Comparison
- P401D (XCZU4EV): 192K Logic Cells, 728 DSP Slices — good for general MIMO, spectrum monitoring, lighter DSP pipelines
- P501D (XCZU5EV): 256K Logic Cells, 1248 DSP Slices — extra DSP & BRAM for phased array, complex real-time processing
Software & Package
It works with common open-source SDR stacks and has partial compatibility with ADI FMCOMMS5 firmware. Standard kit includes metal enclosure, schematics, demo code and tutorials. Custom secondary development is available.
Applications: phased array radar, spectrum surveillance, GNSS receivers, UAV payloads, test & measurement, wireless algorithm research.
r/RTLSDR • u/Rough-Bat4040 • 1d ago
Longbow Scanner (coming soon)
Longbow: a desktop police/fire/EMS scanner for an RTL-SDR Blog V3 (It's all i have to test with) (Windows, receive only)
- Follows P25 Phase I trunked systems with voice, and scans analog channels. P25 Phase II coming soon.
- SDS200-style face: DIGITAL / ANALOG / ALL / OTHER presets, lists, avoids, hold, Simple and Detail screens
- Encrypted calls are marked and skipped
- Names unknown talkgroups from radio-ID clues; every call is logged
- TEXT screen: live call transcripts made on your own NVIDIA GPU, no cloud
- Waterfall that marks the control channel, the voice channels and every active call, with why each one is or isn't playing
- Aircraft map from its own ADS-B decoding on 1090 MHz: tracks, altitude, speed, type and registration, emergency and military alerts
- WEATHER button: NOAA Weather Radio, live NEXRAD radar, NWS alerts, on-air SAME alert decoding
- Workbench: listen anywhere from 24 to 1766 MHz in NFM, WFM, AM, SSB and CW, with recording
- Plugins for DTMF, two-tone pages and audio filters
- Phone and tablet control over your own private network; one-click installer with updates from the menu
r/RTLSDR • u/rafafunt • 1d ago
Software Try new RTL-SDR scanner in your browser, no receiver needed.
Note: the web demo uses simulated signals (no RF). Real scanning needs an RTL-SDR and the downloadable program
Earlier this week I shared information about a new SDR scanner, FalconSDR. Today instead of reading boring feature list you can just see how it works in your browser:
You don't need to download anything or connect your RTL-SDR to test how it works. On this website you can control virtual RTL-SDR and listen to simulated transmissions and recordings on different radio bands.
If you like it and want to scan or record real transmissions with your RTL-SDR visit https://github.com/rafafunt/FalconSDR (project is free and open source) If you have any questions, feel free to ask in the comments. Program and demo are currently available in English and Polish language but you can ask for making other translation.
I don't want to spam in this subreddit so this is probably the last post about this project from me here. If you are interested watch it on github.
r/RTLSDR • u/Resident-Breath7449 • 2d ago
Anyone decoded a Consumers Energy (Michigan) gas meter? Itron 100G DLS, zero packets
Southeast Michigan, Consumers Energy gas (DTE electric). New Itron 100G DLS ERT on an AC-250 (photo attached).
I've run rtlamr / rtlamr2mqtt with every message type, filtered and unfiltered, including a 24-hour capture, and gotten zero gas packets. My Neptune R900 water meter decodes fine on the same setup.
Has anyone in Consumers territory gotten their gas ERT to decode? Or is it encrypted or fixed-network only? Thanks!
r/RTLSDR • u/ethan_partidas • 2d ago
Software What's the most annoying part of your RTL-SDR setup? (dev doing research, not selling anything)
I'm a developer working on SDR software and trying to understand how people actually use their dongles before I build the wrong thing. Nothing to sell or sign up for, just reading answers.
If you have a minute, any of these:
- What did you last use your SDR for, and what software did you use?
- What part of that took longer or was more frustrating than it should have?
- Is there something you tried to do and gave up on? What stopped you?
- What's your setup (dongle, antenna, upconverter/filters, OS)?
Short answers are great. Rants are also great. Thanks!
NA4GJ
r/RTLSDR • u/Curious-Strike-8863 • 2d ago
Two practical books for learning GNU Radio, now available in French and English
r/RTLSDR • u/Bulky_Salad4056 • 2d ago
ACARS and the problem with MLAT
I use ADSB.im on RI 4 to feed ADS-B and AIS, everything works fine. I bought a third SDR dongle and antenna to play with ACARS / VDL2 / HFDL.
ACARS works and receives messages, but I noticed that the MLAT light was red and the web stats pages that I feed showed errors that it was not counting the MLAT.
I thought there was a bottleneck somewhere on the RP4, so I took a second RP4 just for ACARS only. I noticed that when it's set to ACARS only, I still have the on map blue ADS-B and green ACARS labels.
I think the ADS-B Feeder sees the planes twice and the MLAT twice, and it interferes with the MLAT calculation and sending data.
CPU usage -30% , RAM -1GB, and temps are fine, no undervolting. I'm using active USB hub for dongle. I don't see anything in the options that I could change.
I tried it on 2 RP 4 on official and beta ADS-B Feeder Image. How to set what to change to have 3 SDR for ADS-B, AIS and ACARS on 1 RP4 without problems with MLAT? I can use 2 RP4s but I prefer to have everything on 1.
r/RTLSDR • u/Illustrious_Car9226 • 2d ago
Software [Projet perso] Écouter la radio en continu et faire des recherches dedans avec une IA locale (RTL-SDR + Faster-Whisper)
Bonjour à tous,
Je partage un petit projet open-source que je viens de finaliser et packager : **RadioTranscribe-Store**.
### De quoi s'agit-il ?
L'idée était de fabriquer une sentinelle d'écoute autonome pour enregistrer et indexer passivement les actualités de la bande FM (sur France Inter par exemple), de manière 100 % locale, sans envoyer la moindre seconde d'audio dans le cloud.
### Comment ça tourne sous le capot ?
**Capture radio :** une simple clé logicielle USB (RTL-SDR) capte le flux FM via `rtl_fm` et `ffmpeg`.
**Préservation du matériel :** les flux audio temporaires sont écrits et traités directement en mémoire vive (`/dev/shm`), ce qui évite d'user les disques SSD en écriture continue H24.
**Transcription IA :** le modèle Faster-Whisper (`large-v3`) tourne en local sur processeur (quantification int8).
**Filtre anti-hallucination :** élimination des sous-titres fantômes récurrents de Whisper.
**Stockage hybride :**
- Historique chronologique dans **MariaDB**.
- Recherche sémantique vectorielle (RAG) dans **ChromaDB**.
On peut ensuite simplement poser des questions ou chercher des thèmes en langage naturel dans un terminal pour retrouver les extraits diffusés à l'antenne et leur date de passage.
Tout le projet (scripts, automatisation de l'installation et service systemd) est documenté ici :
https://github.com/TVIEIL/RadioTranscribe-Store
Si vous avez des remarques, des suggestions d'améliorations ou des questions sur l'intégration SDR/IA, je prends volontiers vos retours !
r/RTLSDR • u/http-brandon • 3d ago
DIY Projects/questions Anyone recording Starlink Ku-band with an LNB + SDR near buildings? (research data request)
Hi all, I'm a researcher at a university lab in Hong Kong, working on positioning with LEO satellites in cities. I'm looking for raw Starlink downlink recordings where buildings block part of the sky.
What would help most:
- An LNB/LNBF (or horn) + SDR (RTL-SDR, HackRF, USRP, etc.) recording the Ku-band downlink (~10.7–12.7 GHz)
- Receiver sitting still at ground level next to buildings, ideally a street with tall buildings on both sides
- Bonus: a second receiver on a nearby roof recording at the same time
- GPS or NTP-synced timestamps and a rough location (street-level is fine, no need for your address)
- 10–60 minutes is plenty
Already have old recordings sitting on a drive? Those count too, even if the blockage was accidental.
Not looking for dish app screenshots or speed tests this time, just the raw RF.
Anything used would be credited in the paper's acknowledgments (or however you'd like to be credited). Happy to answer questions about setup. Comment or DM me. Thanks!
r/RTLSDR • u/nutstobutts • 3d ago
I was a Minuteman III missileer. I built a site fed from two KiwiSDRs on 11175 kHz. It machine-copies EAMs and lets you listen live
From 2012 to 2016 I was a missileer at F.E. Warren AFB. I sat (and slept) 100 feet underground, ready to launch 10 Minuteman III nuclear missiles.
The orders would have come as an Emergency Action Message. I had no idea that the same messages go out in the clear on HF, or that people around the world have been logging them for decades.
So I built a site that listens and logs the messages with SDRs. Two KiwiSDRs feed it, the KPH receiver at Point Reyes and one in Iceland, both on 11175 USB.
When a message starts it’s recorded, a waterfall is captured, and speech-to-text transcribes it. That’s what the 30 characters (56HETY) are in the picture. The machine copy is usually rough, so anyone can correct it by ear. And you can listen live as well.
I'm trying to make the site as interactive and informative as possible, so if you have any ideas for that, please let me know.
Site: missileer.watch
The full story is in my r/shortwave post from Thursday: https://www.reddit.com/r/shortwave/s/A9mz70qF8l
Happy to answer any questions!
r/RTLSDR • u/Haunting-Hold8293 • 3d ago
I built my very own WSJT-X fork with PSK Reporter integration, SDR support and experimental digital mode(s)
r/RTLSDR • u/NeighborhoodSad2350 • 3d ago
Software "I built", "I made"
Come to think of it, I used to click on titles like that here, expecting to find inexpensive DIY projects or wildly imaginative ideas…?
You guys feel the same way, right?
r/RTLSDR • u/Special-Return9017 • 3d ago
Software ADS-B Now On SDR++ UPDATE: 1
New update: Added Aircraft Table & Majorly Improved the decoding performance. By Claude Free Tier. Added a MGS/S Counter

Previously 2.0 to 6.0 MSG/S now it peaked 70 MSG/S with the performance improvement with just using the same WiFi antenna on RTL SDR V4
Added a Feature whenever it detects Aircraft location. it Automatically sets your viewing location to Aircrafts position. (In default its set to Germany every startup) By DeepSeek
I will be planning to release this Module/Plugin in a week
Is there something i missed or forgot to add?
r/RTLSDR • u/Own_Event_4363 • 3d ago
PDW pager decoding fun
Finally found out where we can look up radio frequencies in Canada, the TAFL search. Tried some hospital pager frequencies, but seem to also get City of Toronto water treatment plants... EFFL Effluent tank is full. Blurred the full email of the Toronto water department. Not sure where the zone humidity is from.
r/RTLSDR • u/BelkSiri • 3d ago
Deux livres pratiques sur GNU Radio maintenant disponibles en français et en anglais
r/RTLSDR • u/6godblockboyjb • 4d ago
Software A wall display for the planes overhead, built on community ADS-B feeds. Looking for 10 beta testers
Not an SDR project itself, but it only exists because of feeders, so this seemed the right place.
It's a full-screen display for a spare TV or old tablet: a map of the planes over your area and one big card at a time for a flight overhead. Positions come from adsb.lol, with adsb.fi as the fallback, so your coverage is whatever the feeders near you give it. I'm planning to add a feeder of my own.
Routes come from the VRS standing data, checked against position, altitude and heading. Anything that doesn't fit is dropped, and the card says "Route unknown".
I'm looking for about 10 people to run it on a real screen for a week from Thursday 29 October, free. Feeders are ideal: you'll know when it's missing a plane you can see on your own receiver.
Waitlist: https://wingwatch.app