Tagged: rtl2832

Discovery Drive Campaign Now Live!

We're extremely pleased to announce that our campaign for our Discovery Drive automatic antenna rotator is now live on Crowd Supply! Pricing is reduced during the campaign period, so check it out soon!

Discovery Drive is an automatic antenna rotator designed for use with our Discovery Dish product, as well as similarly sized antennas such as Wi-Fi grid and Yagi antennas.

A motorized rotator, such as Discovery Drive, enables precise tracking of fast-moving polar orbiting satellites using a satellite dish or directional antenna. Examples of polar orbiting weather satellites include METEOR-M2, METOP, and FENGYUN. Depending on your location, you may also have access to other interesting satellites that dump data over specific regions.

In addition to public weather data, operators and enthusiasts might be interested in using Discovery Drive to track CubeSats, and amateur radio operators may wish to track amateur radio satellites.

Amateur radio astronomy hobbyists can map the galaxy in the hydrogen line spectrum using Stellarium, or custom software to aim a Discovery Dish with H-Line feed, allowing you to scan multiple parts of the sky in one night.

Discovery Drive - A Motorized Antenna Rotator Engineered for Discovery Dish

JoesScanner: A Modern Frontend for Trunking Recorder to Listen, Browse, and Download Calls

Thank you to Joe for submitting news about the release of his project called "JoesScanner". JoesScanner is an app for Windows, Android, and iOS that provides a modern frontend for Trunking Recorder, for listening to, browsing, and downloading trunked radio calls.

A trunked radio call uses dynamically assigned frequencies from a shared pool, so tracking a conversation requires trunking software (e.g., Unitrunker, SDRTrunk, DSDPlus) and typically two RTL-SDRs, one for the control channel and one for the voice channel.

Trunking Recorder is a Windows application for recording/importing audio from trunked radio systems monitored by Unitrunker, SDRTrunk, ProScan, or DSDPlus. While Trunking Recorder already has a web-based browser front-end viewer, Joe was not happy with it and decided to build his own.

Joe writes:

Joe’s Scanner is a Windows, Android, and iOS app that connects to a Trunking Recorder (TR) backend and provides a modern front end for listening, browsing, and downloading calls.
The idea is to make TR based setups easier for end users, especially on mobile, while staying lightweight and ad free.

Key features:

- Connects to any Trunking Recorder server over HTTP or HTTPS, with or without username/password
- iOS background audio support
- History browsing with downloadable calls
- If the TR installation provides transcriptions, the app can enable address detection and what3words detection
- Free to use with no ads, and no data harvesting or resale

Background:

I built it because I run my own TR servers and was not happy with the existing client options, so I created what I wanted for my customers.

I am also making it available for anyone to use with their own TR servers for free.

Server owners can optionally apply to have their server listed in the in app directory to simplify setup for their users:
https://joesscanner.com/support/joes-scanner/joes-scanner-server-addition/

Microsoft Store: https://apps.microsoft.com/detail/9n5hbztcnt4t?hl=en-US&gl=US

Google Play: https://play.google.com/store/apps/details?id=app.joesscanner.com

Apple App Store: https://apps.apple.com/us/app/joes-scanner/id6758413482

Joe notes that the code is all open source and is available on GitHub.

JoesScanner - Mobile Interface
JoesScanner - Mobile Interface

CoronaSDR for iOS – A Free Native RTL_TCP Client

Thank you to Silviu YO6SAY for writing in and sharing with us news about the release of his iOS App called "CoronaSDR" which is a native client for receiving from rtl_tcp servers. rtl_tcp is a server program for RTL-SDRs that streams raw IQ data over a network connection.

Unlike Android, iOS does not allow third-party USB devices like the RTL-SDR to run on its devices. But you can set up an rtl_tcp server on a networked PC or Raspberry Pi in your home, and connect to the data stream with an iOS app like CoronaSDR.

Silviu writes:

CoronaSDR is a free, native iOS app that connects to an rtl_tcp server on your local network (no cloud, no subscription).

Current features
• Live spectrum + waterfall (Metal / GPU-accelerated)
• Demod modes: AM / NFM / WFM / USB / LSB / CW
• RF controls: gain, PPM, direct sampling, offset tuning, bias-tee
• Stations with tags + CSV/TSV import/export
• List/range scanning with squelch hold/skip
• Background audio + lock screen controls

Known limitations (early build)
• Built solo so far — no external testers yet
• Most real-world testing to date has been NFM and WFM
• Other modes are implemented, but I’d consider them early until more field feedback comes in

Tested with an RTL-SDR Blog V4 (R828D) on a Raspberry Pi running rtl_tcp.

I’d really appreciate detailed feedback (device + iOS version, tuner type, rtl_tcp command, mode/frequency, and steps to reproduce any issues).
 
CoronaSDR - RTL_TCP Client for iOS Devices.
CoronaSDR - RTL_TCP Client for iOS Devices.

Exploring the Privacy Risks of Tire Pressure Monitoring Systems with RTL-SDR

Tire Pressure Monitoring System (TPMS) privacy concerns are a topic that comes up every now and then. Most modern vehicles have wireless tire pressure sensors that communicate with the vehicle's computer to alert the driver when tire pressure falls below a safety threshold.

The privacy issue is that these TPMS sensors each transmit a unique identifier, so the computer can know which tire is being measured, and not read other vehicles' sensors by mistake. As TPMS is not encrypted in any way, anyone with an RTL-SDR or other similar radio can receive and decode TPMS messages, including the unique identifier. This raises privacy concerns as this can be used to log the presence and movement of individual vehicles. 

A recent academic paper by university researchers showed how researchers deployed simple RTL-SDR + Raspberry Pi-based receivers along a road over a period of 10 weeks. They showed that TPMS transmissions can not only be used to identify, track, and detect the presence and daily routines of individual vehicles, but also to determine the type and weight of the vehicle via pressure readings.  Interestingly, they also note that variations in the weight of an identified vehicle could indicate, for example, whether a truck is loaded or unloaded, or whether there are additional passengers in a car.

The researchers highlight privacy concerns, noting that such data could be collected and sold by data mining companies without the driver's knowledge. 

RTL-SDR + Raspberry Pi for TPMS Monitoring
RTL-SDR + Raspberry Pi for TPMS Monitoring
The TPMS Monitoring Setup
The TPMS Monitoring Setup

Frugal Radio: Beginners Guide to P25 Decoding with the Latest DSD Plus Release

Over on his YouTube channel 'Frugal Radio', Rob has uploaded a comprehensive video detailing how to set up the latest DSD Plus release for P25 Public Safety decoding.

Back in December 2025, we posted about how the DSD Plus team released version 2.547. The release had already been available to DSD Fastlane customers, but it is now available to the public. The new version brings various improvements and features, but it also changes the software signal flow that was used in previous versions.

In the video, Rob explains how to set up the new DSD Plus version, including how to use the new FMP24 demodulator with an RTL-SDR. He then goes on to show the various features, like control channel monitoring mode, getting P25 system data, holding and IDing talkgroups, and setting talkgroup aliases.

HUGE free DSDPlus Update 2026 : Decode P25 Public Safety with your SDR and this beginner guide!

Khanfar Software: Analog Radio Hunter

Recently, M. Khanfar released a new free program, "Analog Radio Hunter," described as a "professional RF analysis and monitoring application built around GNU Radio and Fosphor." The software currently supports RTL-SDR, Airspy, and HackRF. Khanfar writes:

Analog Radio Hunter is a professional RF analysis and monitoring application built around GNU Radio and Fosphor.

It is designed to scan large RF spans, quickly lock onto active signals, and monitor analog transmissions with NFM, AM, or WFM audio demodulation.

  • Real-time FFT + waterfall spectrum display
  • Fast scan with dwell, pause-on-squelch, and skip-ignored channels
  • Detection list with hits, timestamps, and smart deactivation
  • Favorites profiles with monitor and favorites-only scan modes
  • Built-in recorder with auto-record and event log
  • Dedicated WFM broadcast receiver with presets
  • Multi-SDR device support (RTL-SDR, Airspy, HackRF) with auto-detect and device switching
  • NFM and AM audio demodulation (in addition to WFM)
  • Peak-follow in span (auto-tune to strongest signal inside the current MS/s window)
  • Frequency list filtering to skip/mute ignored channels
  • Scan and detection profiles (save/load named presets)
  • PPM correction for RTL-SDR calibration
  • Spectrum interaction controls (cursor readout, click-to-tune, wheel step, drag-pan)
  • Recorder options (record when muted, timestamp/frequency in filename, beep on favorite)
  • WFM de-emphasis selection (50/75 µs) and preset management
  • Audio Output menu with refresh (route audio to speakers, VB-Cable, or USB output)
  • Signal Stability Filter with Min Open + Grace timing and per-target routing
  • Histogram IQ Rec with live IQ follow controls and inspectrum integration
  • Auto Squelch Calibrate (noise floor + margin) for faster field setup
  • Smart Deactivate dual-layer logic (time-based + hit-rate busy rule)
  • Favorites cooldown auto-reactivation for busy channels
  • Favorite TX tones (Tone 1-9), edge selection, and tone test buttons
  • Learning Mode hover guidance for faster onboarding
  • Status bar live metrics for Last, Active, Favorite, Peak SNR, and Level
Unique scanning and detection approach: Traditional sweep scanners only see the center frequency they step to. Analog Radio Hunter monitors an entire chunk of spectrum at once and reacts to peaks inside it. That is a major differentiator.
 

High-Impact Capabilities

  • Wide-span reactive scan engine that hunts activity across a full chunk, not one center point at a time.
  • One-click IQ capture and histogram visualization with follow and idle flow controls.
  • Carrier-resilient channel management using Smart Deactivate + favorites cooldown logic.
  • Field-ready setup speed using Auto Cal squelch and persistent live status metrics.
  • Operator-selectable audio routing to speakers, VB-Cable, or USB audio output devices.
  • Operational clarity from GUI color heatmaps, scan debug reasons, and learning-mode tips.

Signal Stability Filter: Logic and Tuning

  • Purpose: reject short squelch flicker and noisy open/close chatter before actions trigger.
  • Min Open (ms): raw squelch must stay open this long before stable-open is accepted.
  • Grace (ms): stable-open is held briefly after raw close to avoid tiny dropouts.
  • Apply targets: Detection, Rec+Alerts, Scan Hold, and optional Audio Out gating.
  • Start values: Min Open 150-250 ms, Grace 40-80 ms, then tune by channel behavior.

Like his other software, which we previously covered, it is free but not open source. Anti-virus programs may flag the software as suspicious due to heuristics. We believe this to be a false positive, but as with all software that isn't open source, we recommend being highly suspicious and only run it in a sandboxed environment like a VM to be sure.

M Khanfar Analog Radio Hunter
M Khanfar Analog Radio Hunter

Iridium-Sniffer: A Standalone Iridium Satellite Burst Detector and Demodulator

Thank you to Aaron, who is most well known for creating the DragonOS distribution, for writing in and sharing with us a new open-source program he's recently released over on GitHub.

The program is called 'Iridium-Sniffer', and it is a standalone Iridium satellite burst detector and demodulator written in C. Typically, gr-iridium has been used for Iridium demodulation in the past, but it can be clunky and slow on lower-power embedded systems like the Raspberry Pi, as it requires the large GNU Radio dependency.

The program is compatible with iridium-toolkit, which performs the actual decoding and analysis of the Iridium packets demodulated by iridium-sniffer.

If you're not familiar with it, Iridium is a large global communications satellite constellation that provides services such as voice, messaging, and data. An antenna like our RTL-SDR Blog Active Patch antenna, combined with an SDR, can be used to receive these signals. Some data on Iridium is encrypted, but there is some unencrypted data that can be decoded when combining tools like iridium-sniffer and iridium-toolkit.

Iridium-sniffer is compatible with the HackRF, BladeRF, USRP (UHD), and SoapySDR (which includes RTL-SDR). Note that higher-bandwidth SDRs can receive much more of the ~30 MHz Iridium band, and therefore decode more data at once.

The Iridium Satellite Constellation
The Iridium Satellite Constellation

Multimon Pager Decoding on Android

Sarah (aka SignalsEverywhere) has recently released another open-source Android app that enables the multi-signal decoder Multimon-ng to be used on Android. Multimon-ng is a commonly used decoding app, that supports various protocols such as POCSAG/FLEX pagers, as well as DTMF, ZVEI, EAS and more.

The app requires the SDR++ Android app to be running in the background with an SDR like an RTL-SDR connected. The role of SDR++ is to receive the signal and send the demodulated audio over a network connection to the Multimon-NG app, which performs the final decoding.

The app APK can be downloaded from Sarah's website via a minimum $0 donation, or alternatively, built and installed from source.

Multimon-ng on Android!