Tagged: rtl-sdr

SignalsEverywhere: Build an RTL-SDR Based OP25 Radio Scanner with a Mobile Control Head Android App

Welcome back to Sarah from the SignalsEverywhere YouTube channel who has recently returned to producing videos from a hiatus. In her latest video, Sarah shows off her new OP25 Mobile Control Head Android App which allows you to implement a full P25 digital radio scanner at a fraction of the cost of a commercial digital scanner. In the past, Sarah had released a similar application written for the Raspberry Pi but has decided to shift her focus to writing an equivalent Android app that is less clunky and can be deployed for a lower cost. 

The app controls and displays information from the OP25 software that runs on a Raspberry Pi with RTL-SDR connected. It works by using a server application on the Raspberry Pi that manipulates the OP25 instance and its configuration files.

Sarah writes:

The application is a wrapper for OP25 that uses a raspberry pi and an android device to provide users with a mobile control head for their OP25 P25 scanner setup. Currently it's just a basic application but I'll be adding features like automatic site switching, etc.

OP25MCH: https://github.com/SarahRoseLives/OP25MCH

There is also a separate application I call the OP25Display which is just a display for a users existing OP25 instance.

OP25Display: https://github.com/SarahRoseLives/op25display

Build Your Own Digital Radio Scanner With OP25 Mobile Control Head App

A 3D Printed Enclosure with USB Hub for RTL-SDR Blog Units

Over on Hackaday, we've seen a post about Jay Doscher's clever 3D printed enclosure that can hold two RTL-SDR Blog V4 units and a USB hub. The enclosure is designed to make it easy to take the two units mobile, and the USB hub inside means that only one USB connection is required to run the two units.

Jay has also thought about cooling, allowing for space between the two dongles, and adding vent holes. He has also ensured that the SMA ports on the dongles are protected while allowing space to hand-tighten the connectors.

Jay writes that he has tested his enclosure with RTL-SDR Blog V4 units, but given that the dimensions of the V3 (and V2) are the same, it will work for those units too.

A 3D Printed RTL-SDR Blog Enclosure with USB Hub
A 3D Printed RTL-SDR Blog Enclosure with USB Hub

uSDR Software Updated to V1.7.0

Thank you to Viol for writing in and letting us know that his uSDR software has recently been updated to V1.7.0. The uSDR software (not to be confused with the unrelated uSDR hardware) is a lightweight general-purpose multimode program for Windows that supports the RTL-SDR, Airspy, BladeRF, HackRF, LimeSDR, and other SDR radios.

Viol highlights the latest features added in the 1.7.0 update below:

  • Fobos SDR frontend native support, the very new SDR from RigExpert
  • bladeRF API v2.5.0 support, oversampling mode up to 122.88 MHz sample rate (do not forget to update FX3 firmware)
  • advanced IQ playback mode, precise timing and streaming
  • improved DSP routines and memory management, minimized CPU load
  • excellent ruler tool for spectrum frequency and amplitude measurements
uSDR Updated to Version 1.7.0. Images shows FobosSDR support.
uSDR Updated to Version 1.7.0. Images shows FobosSDR support.

YouTube Video Series on Iridium Satellite Decoding with an Airspy, RTL-SDR Blog Patch Antenna and DragonOS

Over on his YouTube channel, Rob VK8FOES has started a new video series about Iridium Satellite Decoding. Iridium is a constellation of low-earth orbiting satellites that provide voice and data services. Iridium was first decoded with low cost hardware by security researchers back in 2016 as mentioned in this previous post. Being unencrypted it is possible to intercept private text and voice communications.

Rob's video is part of a series, and so far only part one has been uploaded. The first video outlines the hardware and software requirements for Iridium decoding and demonstrates the gr-iridium software. An Airspy and RTL-SDR Blog Patch Antenna are used for the hardware, and the software runs on DragonOS.

Rob writes that in part two he will demonstrate the use of iridium-toolkit, which can be used to extract data and recordings from the Iridium data provided from gr-iridium.

Be sure to subscribe to his YouTube channel so that you are notified when part two is released.

Iridium Satellite Decoding Part 1: The Tutorial That Goes Over Your Head, Literally!

DeepRad: Upcoming Modular RTL-SDR System to be CrowdFunded

The company "DeepSea Developments" have recently released news about their upcoming crowdfunding campaign for their 'DeepRad' modular RTL-SDR system. The goal of DeepRad appears to be a modular RTL-SDR that can easily be used as a module on a 'motherboard' PCB of your own design.

DeepRad is currently in the 'Coming Soon' stage on CrowdSupply, and will probably be released for crowdfunding in the next few months.

DeepRad is a modular version of the RTL-SDR, a product beloved by radio enthusiasts. However, DeepRad offers distinct advantages. Its modularity makes integration far simpler, side-stepping the complexities of designing an RTL-SDR from scratch (such as RF considerations and chip stocking issues). DeepRad is a versatile option for integrating many different radio functions into whatever projects you’re working on today.

We want the community to create their own "motherboards" with 1, 3, or as many as 20 DeepRad modules to bring new applications to life. There are three versions of DeepRad we’ll be focusing on for this campaign:

  • DeepRad Module: The bare DeepRad module (no motherboard). The user has to develop a board to use it.
  • DeepRad Single: A single DeepRad module with a motherboard. It has USB Type-C and an antenna connection. It can be used as your regular RTL-SDR with USB.
  • DeepRad Quad: A motherboard with 4 DeepRad modules integrated via a USB hub with a USB Type-A connector.
The DeepRad Quad Motherboard with Four DeepRad Modules

QCSuper: Capture 2G/3G/4G/5G Radio Frames with Qualcomm Phones

In the past, we've shown how it's possible to use RTL-SDRs or other SDR devices together with the Airprobe software to analyze data from 2G GSM mobile phones and towers. (Note that it's not possible to listen in on conversations or read SMS data unless you have the encryption code for the recipient phone. This is only capable of showing cell tower basestation telemetry for example).

While not directly related to SDR, readers might be interested to know that a new piece of software called QCSuper has been released which enables similar analysis capabilities for 2G/3G/4G/5G signals through the use of Qualcomm-based phones and modem hardware. To use it you will need a rooted Android phone. The software accesses a diagnostics mode available in Qualcomm devices and makes the data available for view on Wireshark.

[Also seen on Hackaday]

QCSuper Screenshot
QCSuper Screenshot

Antennas Explained: Finding the Best Antenna for HackRF, RTL-SDR and Other Receivers

Over on YouTube sn0ren has uploaded a well produced video to help beginners to the radio hobby understand antennas. The video explains how antennas work in theory, and how to choose the best antenna for your SDR and application through calculations and use of a Nano VNA.

There is an essential gadget that you will want to get, to get the best antenna performance. But first we need to cover a bit of antenna theory, before we can answer the question of what antenna that is the best one for your HackRF Portapack, or Flipper Zero SubGHZ module, or Meshtastic, Quansheng UV-K5, RTLSDR or other radio devices. This video is covering the bare minimum basics of antenna theory for beginners into the radio hobby.

The best antenna for HackRF Portapack (and Flipper Zero, Meshtastic, Quansheng, RTLSDR, etc.)

SDR# Version 1920 Released

A few days ago SDRSharp version 1920 was released. SDRSharp (SDR#) is a popular Windows program that is affiliated with Airspy SDR dongles, but is compatible with RTL-SDR and various other SDRs as well. The latest version gets rid of the relatively resource heavy Telerik UI library and replaces it with a much lighter weight library.

The author of SDR#, @lambdaprog, notes that v.1920 reduces memory usage by 85% and CPU utilization by 50%. The new version also improves scalability for high sample rates and number of spectrum slices and improves plugin compatibility. Several AOR brand SDRs are also now supported in v.1920.

On the note regarding improved plugin compatibility, we've noticed that in the v.1920 update the IF Average plugin has begun working again. The IF Average plugin is used for Hydrogen line radio astronomy experiments. In the past we had to use older versions of SDR# to make it work. We have updated our Hydrogen line tutorial to reflect this.