SDRSharp Community Plugin Package Now Available

The SDR# developer in conjunction with Rodrigo Pérez have recently endorsed and released a "community plugin package" over on the SDR# downloads page. This consists of a SDR# installer that automatically downloads and installs a whole plethora of SDR# plugins.

In addition to the plugins it also automatically installs the RTL-SDR drivers, and the RTL-SDR (R820T) special interface which has the ability to use decimation and has individual controls for each of the three gain stages. You can also use it to automatically install the LimeSDR and PlutoSDR interfaces.

The .exe is a simple installer and you can select what plugins you want during the install. The installer automatically puts the SDRSharp folder in the C: drive.

SDRSharp Community Plugin Package
SDRSharp Community Plugin Package

The plugins included are:

  • Base Windows SDR Software Package (same as above)
  • Plugin Audio Processor
  • Plugin Audio Recorder
  • Plugin AUX VFO
  • Plugin Avia band 8.33 calculator
  • Plugin Baseband Recorder
  • Plugin Calico CAT
  • Plugin CTCSS decoder squelch
  • Plugin DCS decoder squelch
  • Plugin DDE Tracker
  • Plugin Digital Audio Processor
  • Plugin DSDtcp
  • Plugin File Player
  • Plugin Frequency Lock
  • Plugin Frequency Manager
  • Plugin Frequency Scanner
  • Plugin Gpredict Connector
  • Plugin IF Processor
  • Plugin IF Recorder
  • Plugin Level Meter
  • Plugin LimeSDR
  • Plugin Meteor Demodulator
  • Plugin MPX Output
  • Plugin PAL/Secam TV
  • Plugin Pluto SDR
  • Plugin RTL-SDR 820T
  • Plugin SDRSharp Net Remote
  • Plugin Time Shift

WWV and WWVH Special Messages to Broadcast!

Starting from Monday September 16th and continuing through to October 1st, both WWV and WWVH shortwave time signal transmission stations will broadcast a special message from the Department of Defense to mark the centennial of WWV. These messages will be heard on 2.5, 5, 10, and 15 MHz. In addition from September 28 to October 2 a special WWV event will occur:

The world’s oldest radio station, WWV, turns 100 years on October 1, 2019, and we are celebrating!

From September 28 through October 2, 2019, the Northern Colorado ARC and WWV ARC, along with help from RMHam, FCCW, and operators from across the country, are planning 24-hour operations of special event station WW0WWV on CW, SSB and digital modes. Operations will shift between HF bands following normal propagation changes and will include 160m and 6m meteor scatter. We will be operating right at the WWV site and face a challenging RF environment.

WWV is a [NIST] operated HF station based in Fort Collins, Colorado. It continuously broadcasts a continuous Universal Coordinated Time signal in addition to occasional voice announcements. It has been on the air since 1919 but began continuous broadcasts in 1945 from it’s final site in Fort Collins, Colorado. WWVH is a similar time signal, but based in Hawaii.

The WWV Transmit Building

The WWV time signal can be used to automatically set RF enabled clocks to the correct time. [Andreas Spiess] on YouTube recently uploaded a video where he emulates this signal in order to control clocks within his home. This is a great watch if you’d like to learn more about how these time signals work.

The time format itself is actually pretty simple and it’s possible to emulate with a number of devices from an Arduino to Raspberry Pi and of course Software Defined Radio.

Remote Controller for Clocks (IKEA and others, DCF77, WWVB, MSF, JJY)

Testing Version Two of the NooElec Balun One Nine

Over on YouTube two reviewers have just uploaded videos showing off version two of the NooElec Balun One Nine. Version one of the Balun One Nine is a balun transformer that can be used with long wire and untuned dipole HF antennas to match the impedance with a 50 Ohm SDR. Matching the impedance results in better HF reception and less noise. While it is a balun and hence designed for balanced antennas like a dipole, it is possible to convert it into an unun for long wire antennas by cutting a trace.

In the first video Corrosive from SignalsEverywhere compares version one with version two. He notes that the new Balun uses a higher quality Coilcraft component, a more sturdy terminal connector and includes mounting holes. He notes that the power rating of the balun should also allow for low power transmission. However, when comparing the two in reception there is little difference in actual results between version one and two. 

In the second video TechMinds provides a similar video and also shows the enclosure that they will be providing in a premium version.

Nooelec 9:1 HF Balun Version 2?

New Balun One Nine Version 2 From NooElec

Testing a PCB Patch Antenna and Radiosonde QFH Antenna for Inmarsat and Iridium Reception

Over on his YouTube channel Tech Minds has been testing some antennas for Inmarsat and Iridium L-Band satellite reception. Inmarsat is a satellite service that runs on geostationary satellites, and one can be received from almost anywhere in the world. There are various services, but the ones that are easily decodable are STD-C EGC and AERO. EGC contains text information search and rescue (SAR) and coast guard messages as well as news, weather and incident reports, and AERO is a form of satellite ACARS, and typically contains short messages from aircraft.

In the first video Tech Minds tests what appears to be an as of yet unreleased prototype PCB patch antenna being designed by NooElec. The PCB patch antenna is combined with a SAWBird Inmarsat LNA and an RTL-SDR. With it he's able to receive STD-C and AERO signals.

In the second video Tech Minds tests an L-Band QFH antenna salvaged from a Vaisala weather balloon radiosonde. The QFH is designed for GPS frequencies, but can potentially be used at the slightly higher Inmarsat and Iridium frequencies. Tech Minds combines the QFH antenna with a SAWBird Inmarsat LNA, but unfortunately finds that reception is too weak for any AERO decoding to be possible. However, when used on the higher Iridium frequencies the antenna works well, and he's able to decode packets with Iridium Toolkit.

New Inmarsat Antenna from NooElec

Testing A QFH Antenna For Inmarsat And Iridium

RTL-SDR Blog L-Band Patch Antenna Preview

We note that over the last several months we have been working on our own L-band patch antenna that will cover Inmarsat, GPS and Iridium frequencies all in one. We expect manufacturing to be completed near the end of the month, or early next month.

The antenna is a ceramic patch, and will come in a waterproof enclosure. It will be possible to easily mount the antenna on a window or elsewhere using the standard suction cup and bendy legs tripod included with our dipole kits. Target price is US$39.95 including the suction cup, tripod, 2M coax and shipping, but we may have it initially on sale for a lower price.

This is cheaper than buying an Inmarsat & Iridium LNA, but a bit more than the SDR-Kits patches that they brought out a few weeks ago. Although performance of our patch is much better. Keep an eye out for the initial information post coming in the next few days.

RTL-SDR Blog L-Band Patch Preview (RTL-SDR for Scale)
RTL-SDR Blog L-Band Patch Preview (RTL-SDR for Scale)

A Wall Mounted SatNOGS Ground Station Monitor

If you weren't already aware,  SatNOGS is an open source project that aims to make it easy for volunteers to build and run RF ground stations (typically based on RTL-SDR hardware) that automatically monitor satellite data, and upload that data to the internet for public access. This is very useful for low budget cubesats launched by schools/small organizations that don't have the resources for a worldwide monitoring network as data can be collected from all over the world no matter where the satellite is.

Over on the SatNOGS Libre Space forums, user cshields have posted about his near wall mounted SatNOGS monitoring station. With the station he's able to monitor the status of his SatNOGS station via an LCD screen and see the location of satellites that next in the queue to be received. There are also some status lights and LCD text screen for monitoring the SatNOGS rotator hardware.

The station consists of a Raspberry Pi 4, 7" LCD display, 500 GB SSD, RTL-SDR Blog V3, and an Arduino with 16x2 LCD and NeoPixel. cshields post covers the full details of the build.

[Also seen on Hackaday]

SatNOGS Ground Station Monitor
SatNOGS Ground Station Monitor

A Guide to Compiling Updated NanoVNA Firmware

Thank you to Ohan Smit (ZS1SCI) for submitting his guide that shows us how to compile the latest NanoVNA firmware from the source code. The NanoVNA is an open source VNA project by @edy555 and ttrftech that has recently become extremely affordable at less than US$50 for a fully assembled unit thanks to Chinese manufacturing (or a little more if you order it via Amazon).

As the NanoVNA project is open source the code is ever evolving and the units that ship from China now come with older firmware installed. If you want to test the very latest experimental code, you need to compile it on a PC, and then flash the firmware into the NanoVNA. Ohan's guide covers this all. For example, one recent update now enables time-domain reflectometry for measuring coax cable length, which we explored in a previous post.

Alternatively according to the GitHub readme, it is also possible to use a docker image which will remove the need to install the arm tool chain. Ready to flash images are also released every few days over on the GitHub release page, although these won't include the very latest or experimental changes.

The NanoVNA
The NanoVNAnano

Significantly Improving RTL_TCP’s Performance with Ring Buffers

Thank you to an anonymous contributor for bringing to attention a two part blog post by Stephen Blinick. Stephen's post details how the performance of rtl_tcp can be significantly improved by modifying to code to use a ring buffer instead of using semaphore based locking. If you weren't aware, rtl_tcp is a program that allows you to run your RTL-SDR remotely, and connect to it over a network connection.

The result is a tremendous performance improvement in rtl_tcp according to Stephen. Before the changes he noted that his Raspberry Pi 3B+ could only support a sample rate of 1.92 MSPS over WiFi, and even that had 1-2 seconds of lag. After the ring buffer changes his Pi 3B+ can handle the maximum sample rate of 3.2 MSPS with zero lag. On his Pi Zero W he can achieve a sample rate of 1.92 MSPS over WiFi with minimal lag, whereas before he could only achieve 0.92 MSPS with huge 5-10 second of lag.

The patch is available as a pull request over on the Osmocom GitHub.

Unfortunately this patch might not be included in the official upstreamed Osmocom drivers because Stephen submitted the patch as a pull request to the GitHub, and Osmocom only accept patches via their mailing list. If anyone reading this is familiar with the Osmocom patch submission requirements, we'd like to encourage you to help submit this patch for consideration.

Ring Buffer Patch for rtl_tcp
Ring Buffer Patch for rtl_tcp

SignalsEverywhere is Hosting An SDR Hack Chat

[Corrosive/SignalsEverywhere] will be hosting a Software-Defined Radio Hack Chat over on [Hackaday.io] on Wednesday September 18th at 12 PM PDT.

If you’re unfamiliar with Hackaday’s Hack Chat, these are chat sessions with individuals experienced in various fields in which anyone can join in and ask questions during the session. The Hackaday team has run these events with many guest hosts covering a plethora of interesting topics. This however, will be the first Hack Chat revolving around Software Defined Radio.

The hack chat will discuss many sub-hobbies of the SDR world from Amateur Radio and satellite operation to things like weather sonde tracking, monitoring and more.

If you have some SDR questions that have been burning you may want to hop on this session as it’s a one-day event, of course there is always our [Forums] where our community is happy to answer your questions as well.