Over on YouTube a talk about decoding water and electricity usage meters with an RTL-SDR has been uploaded from the 2015 Camp++ conference in Hungary. The presenter, Stef writes:
Budapest public utilities started to roll out some new metering devices for water and heating (at least in my block). The plumbers who should install these could not tell me about the privacy protections considered, as I was a bit worried about the things leaking information over radio-waves, so I built a radio and reversed the messages.
The talk shows how the presenter was able to reverse engineer the FSK wireless protocol of his heating meter with help from some patent information that he found on the web. Using a GNU Radio flow graph that he created he was able to extract information such as total energy consumption and temperature readings.
Being a security themed conference, the presenter also discusses some of the security risks associated with wireless meters such as whether or not the meter can be used to detect if someone is currently at home.
The BA5SBA direct sampling kit is a kitset PCB that combines with a standard (included) RTL-SDR dongle in order to enable the direct sampling mod. The direct sampling mod is a hardware modification that can be applied to any RTL-SDR dongle in order to enable HF reception capabilities. The BA5SBA kit improves upon some of the problems with the direct sampling mod by adding additional features such as a low pass filter to block broadcast FM interference, a matching transformer to better match the RTL2832U’s input impedance, extra power supply filtering, SMA connectors for HF and VHF/UHF (UV), an aluminium case and a bias tee.
The BA5SBA direct sampling RTL-SDR can be bought as a kit that requires hand assembly for about $30 USD or as a fully assembled product for about $50 USD. It is usually listed on Amazon and eBay as a “100KHz-1.7GHz full band UV HF RTL-SDR USB Tuner Receiver/ R820T+8232 Ham Radio”
Recently, RTL-SDR.com reader Simon (MW0SGD) bought one of these kits and discovered that the English instructions were very rare and hard to come by. We’ve decided to post these English instructions here for any future buyers who may search for them as this post should show up on Google. Simon also notes that “most of the instructions on the internet wind the inductors on a 5mm former. This says to use a 3mm one, which I did and it works ok.”
Recently RTL-SDR.com reader Slaven Krilic wrote in to use to announce his project called MNM4SDR which stands for Monitoring Network Manager for RTL-SDR. The software allows you to set up a remote Raspberry PI embedded computer with an RTL-SDR dongle attached and access it remotely through a Windows PC GUI.
Unlike other server software such as rtl_tcp, raw IQ data is not sent over the network. Instead audio is first compressed in lossless FLAC or OGG formats. This allows you to use much slower network or internet connections. The software also allows you to collected RF scans over a large bandwidth in a similar way to rtl_power.
The software works over an SSH connection and requires that you have RTL-SDR and VLC set up on your Rasperry Pi first.
Rtl_power is a tool that allows you to create wide band signal strength heat maps over a long length of time. It works by very quickly hopping across the spectrum, capturing the RTL-SDR bandwidth of about 2 MHz at a time, and then displaying it on a heat map. This is useful for seeing what frequencies are active and at what times.
Unitrunker is software that allows you to follow trunked voice conversations, and SDR-Console V2 is a general purpose receiver, similar to other software such as SDR#. The authors write:
This applications sole purpose is to allow Universal Trunker (aka Unitrunker) to control the tuning frequency of individual VFO’s in SDR Console v2. This is achieved by translating Unitrunker Receiver Control commands into a format accepted by SDR Console. Communication occurs over virtual com / serial ports.
Uni-SDR Link has been tested on Windows 7 & Windows 8 and requires .NET Framework version 4.0 or greater.
Just download & launch. No installation required.
The Uni-SDR-Link.chm file contains help for the application should be placed in the same directory as the Uni-SDR-Link.exe.
To commemorate the 40th Anniversary of the Apollo-Soyuz mission the International Space Station (ISS) is set to transmit 12 Slow Scan TV (SSTV) images this weekend. The images are set to transmit Saturday morning, July 18 10:30 UTC and will run through until Sunday, July 19 21:20 UTC, but they note that the dates are tentative and could be subject to change. The images will be transmitted at 145.80 MHz and will probably be sent in the PD180 SSTV mode with 3 minute breaks between each transmission.
SSTV is a type of radio protocol that is used to transmit low resolution images over radio. An RTL-SDR with appropriate antenna can be used to receive these images from the ISS. The signal is usually quite strong, so even a simple whip or long wire antenna may receive these images if placed in a good unobstructed view of the sky.
As with the last ISS SSTV event we suggest that to decode the images you use SDR# and pipe the audio into MMSSTV, a freeware SSTV decoding software program. We also suggest using the settings recommended by “happysat”, which are enabling “Auto slant” and “Auto resync” under Options->Setup MMSTV->RX.
To know when the ISS is overhead you can track it online using heavens-above.com or isstracker.com. If using heavens-above to predict pass times remember to set it to show all passes, not just the visible ones. Received SSTV images can be submitted to the ARISS Gallery.
40 years ago this week, the historic joint Apollo-Soyuz mission was conducted. Apollo-Soyuz (or Soyuz-Apollo in Russia) represented the first joint USA-Soviet mission and set the stage for follow-on Russia-USA space collaboration on the Space Shuttle, Mir Space Station and the International Space Station. The Soyuz and Apollo vehicles were docked from July 17-19, 1975, during which time joint experiments and activities were accomplished with the 3 USA astronauts and 2 Soviet cosmonauts on-board. Apollo-Soyuz was the final mission of the Apollo program and the last USA human spaceflight mission until the first space shuttle mission in 1981.
To commemorate the 40th anniversary of this historic international event, the ARISS team has developed a series of 12 Slow Scan Television (SSTV) images that will be sent down for reception by schools, educational organizations and ham radio operators, worldwide.The SSTV images are planned to start sometime Saturday morning, July 18 and run through Sunday, July 19. These dates are tentative and are subject to change. The SSTV images can be received on 145.80 MHz and displayed using several different SSTV computer programs that are available on the Internet.
Also, as a special treat, on Saturday July 18 the ISS cosmonauts will take time out to conduct an ARISS contact with students attending the Moon Day/Frontiers of Flight Museum event in Dallas Texas. This Russian cosmonaut-USA student contact is planned to start around 16:55 UTC through the W6SRJ ground station located in Santa Rosa, California. ARISS will use the 145.80 MHz voice frequency downlink (same as the SSTV downlink) for the Moon Day contact. More details about these contacts are provided at Upcoming Contacts.
The ARISS international team would like to thank our ARISS-Russia colleague, Sergey Samburov, RV3DR, for his leadership on this historic commemoration.
An example SSTV image from the last ISS SSTV event which was to commemorate first man to space Yuri Gagarin’s would be 80th birthday.
At the recent 2015 Society of Amateur Radio Astronomers (SARA) Conference Ciprian Sufitchi (N2YO) presented a paper titled “Detecting meteor radio echoes using the RTL/SDR USB dongle” (pdf). His paper introduces the RTL-SDR, the theory behind forward scatter meteor detection as well as the practical application of the RTL-SDR to meteor detection. Ciprian summarizes meteor scatter as the following:
When a meteor enters the Earth’s upper atmosphere it excites the air molecules, producing a streak of light and leaving a trail of ionization (an elongated paraboloid) behind it tens of kilometers long. This ionized trail may persist for less than 1 second up to several minutes, occasionally. Occurring at heights of about 85 to 105 km (50-65 miles), this trail is capable of reflecting radio waves from transmitters located on the ground, similar to light reflecting from a mirrored surface. Meteor radio wave reflections are also called meteor echoes, or pings.
In the paper he explains how analog TV transmissions are the best for meteor scatter, but unfortunately these been discontinued within the USA. Instead he has been able to use analog TV transmitters from Canada, who still transmit this type of signal. He shows that about half of the USA could use the transmitter he is using for meteor scatter, which is based in Ontario, Canada.
Ciprian is also running a very cool live meteor detection stream on his website at livemeteors.com. His setup is located in the DC Metropolitan area and uses a directional Yagi antenna pointed at the Canadian analog TV tower which is broadcasting at 55.237 MHz. The receiver is an RTL-SDR dongle coupled with SDR# and the ARGO software.
Tim Havens is an avid CW operator on the ham bands and primarily uses his Yaesu FTDX-5000 transceiver for this purpose. At the same time he also uses a software defined radio coupled with an upconverter as a panadapter by connecting the SDR to the 9 MHz IF output of the Yaesu.
To get around this Tim decided to use the Airspy in a special configuration. First he used the external clock input of the Airspy to connect to his Jackson Labs “Fury” GPSDO. This device uses GPS satellites to generate a very accurate 10 MHz clock, with almost zero drift. Secondly, to get around the need for an upconverter with it’s own frequency drift he used the ADC1 direct sampling input ports on the Airspy to connect to the 9MHz IF output of his FTDX-5000 through an extra band pass filter and LNA.
Tim writes that he will soon update his post with more images and a video.
Airspy with external GPS clock and ADC1 output connected.
