Category: Applications

SignalsEverywhere: Harold’s Mobile SDR Vehicle Load Out for Amateur Radio

This week on the SignalsEverywhere YouTube channel Harold shows us the mobile SDR and ham radio setup that he's installed on his car. On the roof of his car he's installed several antennas for various amateur radio bands including the 1.25m, 2m, 70cm, 33cm bands, a modified GPS puck antenna for Inmarsat and Iridium reception, and an antenna and GPS pick dedicated for APRS.

Inside the vehicle is a Windows tablet attached to the dashboard which is used for APRS, remotely controlling a scanner radio stored in the trunk and for running SDRSharp. There is also an Android unit installed in the center console which has an RTL-SDR connected. The Android unit runs RF Analyzer, and an ADS-B decoder. As well as SDRs, Harold also runs several standard ham radios within the vehicle.

Amateur Radio Mobile SDR Load Out | SDR Plus 33cm 70cm 2m 1.25m and more!

Decoding PAL Video from a Nintendo with An Airspy SDR Part 2

Oona combines composite output for color images.
Oona combines composite output for color images.

Last week we posted about Oona Räisänen's ([Windytan] and @windyoona) project to capture live video from her 1985 Nintendo Entertainment System (NES) using an Airspy SDR. In order to avoid expensive Video Capture cards which didn't work on her Mac, she used an Airspy SDR to decode the PAL composite video output of the NES. Last week she had black and white video working.

This week she has full color working, and has on her blog posted a write up about her project with the Airspy and her experiences with trying to find a suitable capture solution. She also goes into some detail about the CPU performance considerations of this solution, noting that there are some performance bottlenecks. She's also uploaded a video showing the results in action.

MacBook decodes PAL video via Airspy R2

Automatically Photographing Passing Aircraft with an RTL-SDR, Pi 3, and IoT Software

Arun Venkataswamy has recently completed a write up about his system which automatically captures images of passing aircraft. It works by using a Raspberry Pi and RTL-SDR to listen to ADS-B broadcasts from aircraft. These broadcasts contain the live current location and altitude of all aircraft in his area. When a landing aircraft is detected to be passing near his house, the Raspberry Pi sends a signal to another Raspberry Pi connected to a camera on his balcony, and that snaps a photo of the passing aircraft.

In terms of software, Arun uses dump1090 as the ADS-B decoder. For communications between the two Raspberry Pi's he uses Node-RED and Mosquitto in order to communicate with MQTT. On the second Raspberry Pi, gPhoto2 captures images from the camera, and then ImageMagick is used to write some text about the aircraft and photo on the image. Arun's post goes in further detail about the code and conditions he uses to determine when a photo should be snapped.

In the past we've posted about a similar project where an RTL-SDR and Raspberry Pi based ADS-B tracker was used with a servo mounted video camera to track and record video of passing aircraft.

Automatically Taking Photos of Passing Aircraft with a Raspberry Pi and RTL-SDR
Automatically Taking Photos of Passing Aircraft with a Raspberry Pi and RTL-SDR

Mike Tests out L-Band STD-C and AERO with a Low Cost Modified GPS Antenna

SDR-Kits.net have begun selling low cost GPS antennas that are modified to receive the Inmarsat satellite frequencies between 1535 MHz to 1550 MHz. They also have a version for Iridium satellites that receives 1610 MHz to 1630 MHz. The antennas are powered by a 3-5V bias tee, so they should work fine with SDRplay, Airspy and RTL-SDR Blog V3 units.

Mike Ladd from SDRplay has recently sent us a guide to receiving AERO and STD-C messages on L-band with the SDR-Kits antenna and an SDRPlay unit running SDRUno (Megaupload link).

AERO messages are a form of satellite ACARS, and typically contain short messages from aircraft. It is also possible to receive AERO audio calls. STD-C aka FleetNET and SafetyNET is a marine service that broadcasts messages that typically contain text information such as search and rescue (SAR) and coast guard messages as well as news, weather and incident reports. Some private messages are also seen. To decode AERO Mike uses JAERO, and for STD-C he uses the Tekmanoid STD-C decoder.

Mike has also created a very handy bank of frequencies for the SDRUno frequency manager which can be downloaded from here.

We note that if you're interested in waiting, at the end of September we will have an L-band patch antenna set available too. Our antenna will work from 1525 up to 1637 MHz. Prototypes have shown have shown good Inmarsat, Iridium and GPS reception. More details coming next month when manufacturing gets closer to finishing up.

Screenshot of the Tekmanoid Decoder from Mikes Tutorial
Screenshot of the Tekmanoid Decoder from Mikes Tutorial

PEPYSCOPE: A Simple Panadapter for HF Radios using RTL-SDR Direct Sampling

Over on GitHub user mcogoni (Marco/IS0KYB) has recently released a new program called Pepyscope. Pepyscope is a simple and fast panadapter application that is designed to be used with direct sampling capable RTL-SDR's such as our RTL-SDR Blog V3 units. Like other panadapters you simply connect the IF output from the hardware HF radio into the input of the RTL-SDR. Then Pepyscope gives you a waterfall display that helps users to easily visualize the spectrum.

Pepyscope is open source and runs on Linux PCs. So far Marco has tested Pepyscope with a KENWOOD TS-180S (single conversion with IF at 8.83 MHz) and an RTL-SDR v3. He has also uploaded a demonstration video on YouTube.

PEPYSCOPE: a simple panadapter for Linux and the RTL-SDR in direct sampling mode

Uplinking to QO-100 with a LimeNET Micro and LimeRFE

The LimeNet Micro is a is a $329 board that combines a Raspberry Pi 3 (compute module) together with a LimeSDR radio. The LimeRFE is an amplifier and filter board accessory designed to be used with LimeSDR units. When a LimeNET Micro and LimeRFE are used together, it is possible to create a transmit capable radio system that can be used for amateur radio.

Daniel Estévez has recently been doing several experiments with the LimeRFE, and this time he's managed to create an uplink capable ground station for the QO-100 amateur radio geostationary satellite. The LimeRFE can output 1W at 2.4 GHz and Daniel writes that with a low cost 2.4 GHz WiFi parabolic grid antenna this is more than enough power to work QO-100.

In terms of software, Daniel is using a Python script that communicates with the Limesuite API for PTT control. For transmitting IQ data generated by GNU Radio he uses limesdr_send. So far he's been able to successfully test a CW beacon, SSB voice and waterfall text generated by gr-paint.

LimeNet Micro + LimeRFE + 2.4 GHz WiFi Antenna = Full QO-100 Solution
LimeNet Micro + LimeRFE + 2.4 GHz WiFi Antenna = Full QO-100 Solution

 

SignalsEverywhere: Driving around with KerberosSDR and Locating a P25 Transmitter

On this weeks episode of SignalsEverywhere, host Corrosive tests out our KerberosSDR coherent RTL-SDR unit for radio direction finding. If you didn't already know KerberosSDR is our experimental 4x Coherent RTL-SDR product. With it, coherent applications like radio direction finding (RDF) and passive radar are possible. Together with the KerberosSDR direction finding Android app it is possible to visualize the direction finding data produced by a KerberosSDR running on a Pi3/Tinkerboard.

In the video Corrosive uses the KerberosSDR together with the recently updated companion Android app to determine the location of a P25 control channel. By driving around with the app constantly collecting data he's able to pinpoint the location within about 15 minutes.

If this interests you, we also have some more driving demo videos available here.

Direction Finding With Kerberos SDR

In addition to his video, Corrosive has also created a very useful calculator that can be used to calculate the required antenna spacing for a circular or linear direction finding array that can be used with the KerberosSDR.

AIS Share App Updated and Magazine Article

Thank you to Christian, programmer of the AIS Share Android App for letting us know about some updates to his AIS Share Android application. AIS Share is a €2 app for Android that allows you to turn an Android device into an AIS receiver together with an RTL-SDR. AIS stands for Automatic Identification System and is used by ships to broadcast their GPS locations in order to help avoid collisions and aide with rescues. An RTL-SDR with the right software can be used to receive and decode these signals, and plot ship positions on a map.

Recent updates to AIS Share have brought improved AIS reception, and updates allowing it to run on the latest Android version. A new video demonstrating the software was also uploaded to YouTube.

AIS SHARE - Android (RTL-SDR AIS receiver)

The App has also been featured in the February 2019 edition the "Practical Boat Owner" magazine (paid magazine with digital editions). The article discusses using AIS Share and an RTL-SDR to stream data to Boat Beacon, which is a popular chart navigation app. A similar but free tutorial on setting up AIS Share and Boat Beacon can be found here.

An excerpt of the Practical Boat Owner AIS Share RTL-SDR Article.
An excerpt of the Practical Boat Owner AIS Share RTL-SDR Article.