Thank you to Jacopo (@lego11/IU1QPT) and Robin (@OK2AWO) for writing in and sharing with us his thoughts about how the SDR community as a whole should move on from the use of WXtoIMG, and instead switch to SatDump, which now has full feature parity with WXtoIMG and additional features too. SatDump is available on Windows, MacOS, Linux, and even on Android. An up-to-date guide for receiving APT with SatDump written by @lego11 can be found on his website here.

Historically, WXtoIMG has been the software of choice for the popular hobby of decoding NOAA APT weather satellite images with RTL-SDR and other SDRs. However, the software has unfortunately been abandoned by its authors for several years, and can now only be found on third-party websites which increases the possibility of downloading a virus. Also, a hack involving a proxy, or directly updating via a powershell script is now required to allow WXtoIMG to update its TLE/ Kepler files due to the celestrak.com to celestrak.org domain name change.

Lego11 also notes a whole host of other issues regarding vulnerabilities and bugs with WXtoIMG:

• The software is ancient and uses obsolete libraries, such as Visual C++ 2002 with .NET. These libraries are the main concern when it comes to WXtoIMG, as I don't find it particularly likely for someone to find an entry point through the software itself. However, a much more likely scenario is a virus abusing the loaded library in memory when WXtoIMG is running and using it to gain an entry point. There are at least 20 vulnerabilities affecting MSVCR70.dll, and all are well known (such as CVE-2007-0025) which makes it even more concerning. CVE-2008-4255 in particular allows for remote code execution on the user's computer, which is very serious. There are certainly many more vulnerabilities that have been exploited regarding MSVCR70, but due to the obsolescence of this software component they are usually not tracked in a CVE.
  
  In either case, just as nobody would use Windows XP as a daily driver in 2024, nobody should use WXtoIMG as a matter of caution, even if the above mentioned vulnerabilities were not present.
  
  As for the bugs, there are many. Here's a list of the most important ones:
   
• Cannot update TLE without external software, complicating the experience for newcomers and adding extra failure points
   
• Map overlay doesn't work properly most of the times, especially if the user starts to receive the satellite before it is at least at 1° elevation
   
• WXtoIMG will crash if Microsoft Defender starts a memory scan during a pass. This will lose the recording
   
• WXtoIMG uses an outdated Win32 API to access audio. This doesn't always work on Windows 11 and Microsoft has stated that it will be removed soon.
   
• WXtoIMG uses ALSA on Linux. The vast majority of Linux distributions don't support ALSA directly anymore, and WXtoIMG cannot work through an audio server (e.g. Pulseaudio) like all Linux applications are supposed to. Therefore, live recording doesn't work on Linux at all.
   
• WXtoIMG doesn't run on MacOS anymore, as the system will refuse execution due to security problems and missing libraries.
   
• WXtoIMG cannot support wav files from e.g. SDR# or SDR++ without using a third party tool such as NOAA-APT.
   
• If a user moves or copies a recorded WAV file (see above), the map overlay will no longer work.
   
• WXtoIMG is especially sensitive to concurrent CPU usage, which will result in "tears" on the image (as is evident on the images in the guy's tutorial). It cannot handle multitasking well on systems more modern than Windows XP due to changes in how the CPU scheduler works in more modern kernels.
   
• WXtoIMG will lock up and then crash if the user starts it without first having updated TLEs due to missing NOAA-17. This is very serious, as it happens to newcomers all the time. It is one of the top support request emails/messages I receive. It is not possible to fix this crash easily.
   
• WXtoIMG doesn't have updated coefficients for calibration, therefore NOAA-15 will look excessively cold compared to other satellites.

AMSAT-UK is pleased to announce that the 2024 Colloquium will take place alongside the RSGB Convention at Kents Hill Park Conference Centre, Milton Keynes, MK7 6BZ on the weekend of 12/13th October 2024.

As in previous years, the AMSAT-UK Colloquium will run as a separate stream within the RSGB Convention and will include presentations on a variety of satellite and space related topics.

The Annual General Meeting of AMSAT-UK will take place during the colloquium.

An AMSAT Gala Dinner will be held on the evening of Saturday 12th October at the Marriott Delta Hotel on Trimbold Drive, Kents Hill, Milton Keynes MK7 6HL. Attendance is restricted this year at the hotel and a limited number of tickets are on sale via the AMSAT-UK Online Shop https://shop.amsat-uk.org/

The cost of the Gala Dinner is £39 per person and includes a three course meal with tea / coffee at its conclusion.

Alongside the Gala Dinner, AMSAT-UK has negotiated a deal at the Marriott Delta for the evening of Saturday 12th October 2024. These rooms include breakfast on Sunday 13th and are priced at £89 per room for single occupancy. Tickets for the Gala Dinner can be purchased on the AMSAT-UK Online Shop.

Bookings for the Gala Dinner are now available on the AMSAT-UK Shop, but must close on 1st October 2024 unless sold out sooner, so please book early to avoid disappointment.

Entrance to the RSGB Convention is managed by the RSGB and you will be required to purchase Day Tickets for the Saturday and/or Sunday to attend the AMSAT-UK Colloquium.

RSGB Convention booking is at https://rsgb.org/main/rsgb-2024-convention/

The schedule of Colloquium talks will be released closer to the date.

In one of her latest videos on YouTube, Sarah from the SignalsEverywhere channel shows how we can use a program called "IZ8BLY Phase 3D (AO-4) Satellite Decoder" to decode the 'Mid-Beacon' on the QO-100 satellite. QO-100 is a commercial geostationary communications satellite that also contains a popular transponder for amateur radio.

However, there is also an interesting beacon called the mid-beacon that can be decoded, which provides some information about the satellite. In the video, Sarah shows how this beacon can be decoded with the software from IZ8BLY. As QO-100 is only visible from Europe, the Middle East and Africa, Sarah uses a WebSDR to receive the signal from the USA, then pipes the audio into the IZ8BLY decoder via Virtual Audio Cable.

E-members of AMSAT-UK can now download the July 2024 edition of OSCAR News, issue 244, here.

The paper edition edition will be sent to postal members and should arrive in the next 2-3 weeks.

In this issue:
• From the Secretary’s Keyboard
• Satellite News
• ARISS International Face to Face Meeting 2024 and 40th Celebration of Amateur Radio on Human Spaceflight by Ciaran Morgan, M0XTD
• QO-100 School contacts by John M5JFS
• FUNcube+ AMSAT-UK’s Next Mission by David Bowman, G0MRF
• Assessing Path Loss Due to Weather in Newfoundland by David Bowman, G0MRF
• VO1/M0XUU Operation from Newfoundland by R. Gopan M0XUU
• The QO-100 Challenge from VO1 by Graham, G3VZV
• VO1NAR Beacon by Graham Dillabough, VO1DZ

In ON245 we will continue with articles on the QO-100 Challenge from the VO100QO

AMSAT-UK FUNcube Mission Patch

Membership of AMSAT-UK is open to anyone who has an interest in amateur radio satellites or space activities, including the International Space Station (ISS).

E-members of AMSAT-UK are able to download the quarterly publication OSCAR News as a convenient PDF that can be read on laptops, tablets or smartphones anytime, anyplace, anywhere. Join as an E-member at Electronic (PDF) E-membership

PDF sample copy of “Oscar News” here.

Join AMSAT-UK using PayPal, Debit or Credit card at
http://shop.amsat-uk.org/

E-members can download their copies of OSCAR News here.

Following on from my article about my QO-100 Satellite Ground Station Complete Build, this article goes into some detail on the Node-RED section of the build and how I put together my QO-100 Satellite Ground Station Dashboard web app.

The Node-RED project has grown organically as I used the QO-100 satellite over time. Initially this started out as a simple project to synchronise the transmit and receive VFO’s so that the SDR receiver always tracked the IC-705 transmitter.

Over time I added more and more functionality until the QO-100 Ground Station Dashboard became the beast it is today.

Looking at the dashboard web app it looks relatively simple in that it reflects a lot of the functionality that the two radio devices already have in their own rights however, bringing this together is actually more complicated than it first appears.

Starting at the beginning I use FLRig to connect to the IC-705. The connection can be via USB or LAN/Wifi, it makes no difference. Node-RED gains CAT control of the IC-705 via XMLRPC on port 12345 to FLRig.

To control the SDR receiver I use GQRX SDR software and connect to it using RIGCTL on GQRX port 7356 from Node-RED. These two methods of connectivity work well and enables full control of the two radios.

The complete flow above looks rather daunting initially however, breaking it down into its constituent parts makes it much easier to understand.

There are two sections to the flow, the GQRX control which is the more complex of the two flows and the comparatively simple IC-705 section of the flow. These two flows could be broken down further into smaller flows and spread across multiple projects using inter-flow links however, I found it much easier from a debug point of view to have the entire flow in one Node-RED project.

Breaking down the flow further the GQRX startup section (shown below) establishes communication with the GQRX SDR software via TCP/IP and gets the initial mode and filter settings from the SDR software. This information is then used to populate the dashboard web app.

The startup triggers fire just once at initial startup of Node-RED so it’s important that the SDR device is plugged into the PC at boot time.

All the startup triggers feed information into the RIGCTL section of the GQRX flow. This section of the flow (shown below) passes all the commands onto the GQRX SDR software to control the SDR receiver.

The TCP RIGCTL -> GQRX node is a standard TCP Request node that is configured to talk to the GQRX software on the defined IP Address and Port as configured in the GQRX setup. The output from this node then goes into the Filter RIGCTL Response node that processes the corresponding reply from GQRX for each message sent to it. Errors are trapped in the green Debug node and can be used for debugging.

The receive S Meter is also driven from the the output of the Filter RIGCTL Response node and passed onto the S Meter function for formatting before being passed through to the actual gauge on the dashboard.

Continuing down the left hand side of the flow we move into the section where all the GQRX controls are defined.

In this section we have the VFO step buttons that move the VFO up/down in steps of 10Hz to 10Khz. Each button press generates a value that is passed onto the Set DeltaFreq change node and then on to the Calc new VFO Freq function. From here the new VFO frequency is stored and passed onto the communications channel to send the new VFO frequency to the GQRX software.

The Mode and Filter nodes are simple drop down menus with predefined values that are used to change the mode and receive filter width of the SDR receiver.

Below are the HAM band selector buttons, each of these will use a similar process as detailed above to change the VFO frequency to a preset value on each of the HAM HF Bands.

The QO-100 button puts the transmit and receive VFO’s into synchro-mode so that the receive VFO follows the transmit VFO. It also sets the correct frequency in the 739Mhz band for the downlink from the LNB in GQRX SDR software and sets the IC-705 to the correct frequency in the 2m VHF HAM band to drive the 2.4Ghz up-converter.

The Split button allows the receive VFO to be moved away from the transmit VFO for split operation when in QO-100 mode. This allows for the receive VFO to be moved away so that you can RIT into slightly off frequency stations or to work split when working DXpedition stations.

The bottom two Memory buttons allow you to store the current receive frequency into a memory for later recall.

At the top right of this section of the flow there is a Display Band Plan Info function, this displays the band plan information for the QO-100 satellite in a small display field on the Dashboard as you tune across the transponder. Currently it only displays information for the satellite, at some point in the future I will add the necessary code to display band plan information for the HF bands too.

The final section of the GQRX flow (shown below) sets the initial button colours and starts the Powermate USB VFO knob flow. I’ve already written a detailed article on how this works here but, for completeness it is triggered a few seconds after startup (to allow the USB device to be found) and then starts the BASH script that is used to communicate with the USB device. The output of this is processed and passed back into the VFO control part of the flow so that the receive VFO can be manually altered when in split mode or in non-QO-100 mode.

The bottom flows in the image above set some flow variables that are used throughout the flow and then calculates and sets the RIT value on the dashboard display.

The final section of the flow is the IC-705 control flow. This is a relatively simple flow that is used to both send and receive data to/from the IC-705, process it and pass it on to the other parts of the flow as required.

The IC-705 flow is started via the timestamp trigger at the top left. This node is nothing more than a trigger that fires every 0.5 seconds so that the dashboard display is updated in near realtime. The flow is pretty self explanatory, in that it collects the current frequency, transmit power, SWR reading, PTT on/off status and S Meter reading each time it is triggered. This information is then processed and used to keep the dashboard display up to date and to provide VFO tracking information to the GQRX receive flow.

On the left are the buttons to change band on the IC-705 along with a button to tune to the VOLEMT on the 60m band. Once again there two memory buttons to save and recall the IC-705 VFO frequency.

The Startup PTT Colour trigger node sets the PTT button to green on startup. The PTT button changes to red during transmit and is controlled via the Toggle PTT function.

At the very bottom of the flow is the set transverter IF Freq function, this sets the IC-705 to a preselected frequency in the 2m HAM band when the dashboard is switched into QO-100 mode by pressing the QO-100 button.

On the right of the flow there is a standard file write node that writes the 2.4Ghz QO-100 uplink frequency each time it changes into a file that is used by my own logging software to add the uplink frequency into my log entries automatically. (Yes I wrote my own logging software!)

The RX Audio Mute Control filter node is used to reduce the receive volume during transmit when in QO-100 full duplex mode otherwise, the operator can get tongue tied hearing their own voice 250ms after they’ve spoken coming back from the satellite. This uses the pulse audio system found on the Linux platform. The audio is reduced to a level whereby it makes it much easier to talk but, you can still hear enough of your audio to ensure that you have a good, clean signal on the satellite.

As I said at the beginning of this article, this flow has grown organically over the last 12 months and has been a fun project to put together. I’ve had many people ask me how I have created the dashboard and whether they could do the same for their ground station. The simple answer is yes, you can use this flow with any kind of radio as long as it has the ability to be controlled via CAT/USB or TCP/IP using XMLRPC or RIGCTL.

To this end I include below an export of the complete flow that can be imported into your own Node-RED flow editor. You may need to make changes to it for it to work with your radio/SDR but, it shouldn’t take too much to complete. If like me you are using an IC-705 and any kind of SDR controlled by GQRX SDR software then it’s ready to go without any changes at all.

More soon …

A couple of years ago I built a Matrix Synapse server and connected it to the decentralised global Matrix chat network that is federated world wide by enthusiasts who host their own Matrix servers. Due to the enthusiasm for a decentralised network the Matrix has grown exponentially and is now an established force in the world of Opensource global communication services.

When I built my server and configured it online my aim was to bring together an enthusiastic group of Radio Amateurs (Radio HAMs) who could build a friendly, welcoming community where people could share, learn and have fun with other liked minded individuals without all the nonsense you see on commercial social media platforms.

Overtime we’ve increased the number of rooms available in the HAM Radio space and the number of subjects covered. This has grown organically as our community has grown and we’ve ventured together into new areas of the hobby.

From the community a number of projects have spawned including the Opensource.radio Wiki that Mike, DK1MI is sponsoring that aims to detail all the Opensource HAM Radio software, Hardware and projects in one centralised site on the internet. This is a great project and one I am very happy to contribute to.

Thanks to Mike, DK1MI we now also have our own Matrix AllStarLink node available. This is a great resource for the community as it is often not possible for all of us to communicate via the radio waves due to geo-location, time zones, local planning regulations etc. Having this 24/7 internet based resource makes it a lot easier for the community to chat at any time even when propagation on the HF bands isn’t in our favour.

Mike, DK1MI has written an excellent article on the Matrix AllStarNode and more, I highly recommend you take a look at it.

We also have a very active satellite room with regular nets on the QO-100 satellite. With such a great range of rooms and subjects there’s plenty to read and talk about with the community.

If you fancy being part of this growing, enthusiastic group of Radio Amateurs and Short Wave Listeners (SWLs) then click on the link below and come and say hello, a warm welcome awaits!

https://m0aws.co.uk/matrix

More soon …

I get quite a few emails from readers of my blog asking how my QO-100 satellite station is put together and so, I thought perhaps now is a good time to put together an article detailing the complete build.

My QO-100 satellite ground station is built around my little Icom IC-705 QRP transceiver, it’s a great little rig and is ideal for the purpose of driving a 2.4Ghz transverter/up-converter.

Of course all the software used for the project is Opensource and freely available on the internet.

The station comprises of the following building blocks:

• Icom IC-705 Transceiver
• DXPatrol 28/144/433Mhz to 2.4Ghz Up-Converter
• DXPatrol GPSDO Reference Oscillator
• DXPatrol 2.4Ghz 5/12w Amplifier
• Nolle Engineering 2.2 turn 2.4Ghz IceCone Helix Antenna
• 1.1m (110cm) Off-set Dish
• Bullseye 10Ghz LNB
• Bias-T to feed 12v to LNB
• NooElec SmartSDR Receiver
• PC Running Kubuntu Linux Operating System
• GQRX SDR Opensource Software
• Griffin Powermate USB VFO Knob
• QO-100 Ground Station Dashboard developed using Node-RED
• LMR400-UF/RG58 Coax Cable

To get a good clear view of the QO-100 satellite I have the dish mount 3.2m above the ground. This keeps it well clear of anyone walking past in the garden and beams the signal up at an angle of 26.2 degrees keeping well clear of neighbouring gardens.

The waterproof enclosure below the dish houses all the 2.4Ghz equipment so that the distance between the feed point and the amplifier are kept to a minimum.

The DXPatrol amplifier is spec’d to run at 28v/12w or 12v/5w, I found that running it at 28v produced too much output for the satellite and would cause the LEILA alarm on the satellite to trip constantly. Running the amp at 12v with a maximum of 5w output (average 2.5-3.5w) is more than enough for me to have a 5/9+10 signal on the transponder.

The large 1.1m dish gives me quite an advantage on receive enabling me to hear the very weak stations with ease compared to other stations.

The photo above shows the 2.4Ghz equipment mounted in the waterproof enclosure below the dish. This photo was taken during the initial build phase before I rewired it so, the amplifier is shown connected to the 28v feed. To rewire the amp to 12v was just a matter of removing the 28v converter and connecting the amp directly to the 12v feed instead. This reduced the output from a maximum of 12w down to a maximum of 5w giving a much better (considerate) level on the satellite.

It’s important to keep all interconnects as short as possible as at 2.4Ghz it is very easy to build up a lot of loss between devices.

For the connection from the IC-705 to the 2.4Ghz Up-Converter I used a 7m run of
LMR-400 coax cable. The IC-705 is set to put out just 300mW on 144Mhz up to the 2.4Ghz converter and so it’s important to use a good quality coax cable.

Once again the output from the 2.4Ghz amplifier uses 1.5m of LMR-400-UF coax cable to feed up to the 2.2 turn Icecone Helix Antenna mounted on the dish. This keeps loss to a minimum and is well worth the investment.

The receive path starts with a Bullseye LNB, this is a high gain LNB that is probably one of the best you could use for QO-100 operations. It’s fairly stable frequency wise but, does drift a little in the summer months with the high temperature changes but, overall it really is a very good LNB.

The 12v feed to the LNB is via the coax and is injected by the Bias-T device that is in the radio shack. This 12v feed powers the LNA and associated electronics in the LNB to provide a gain of 50-60dB.

From the Bias-T the coax comes down to the NooElec SmartSDR receiver. This is a really cheap SDR device (<£35 on Amazon) based on the RTL-SDR device but, it works incredibly well. I originally used a Funcube Dongle Pro+ for the receive side however, it really didn’t handle large signals very well and there was a lot of signal ghosting so, I swapped it out for the NooElec SDR and haven’t looked back since.

The NooElec SmartSDR is controlled via the excellent Opensource software GQRX SDR. I’ve been using GQRX SDR for some years now and it’s proven itself to be extremely stable and reliable with support for a good number of SDR devices.

To enhance the operation of the SDR device I have added a Griffin Powermate VFO knob to the build. This is an old USB device that I originally purchased to control my Flex3000 transceiver but, since I sold that many moons ago I decided to use it as a VFO knob in my QO-100 ground station. Details on how I got it working with the station are detailed in this blog article.

Having the need for full duplex operation on the satellite this complicates things when it comes to VFO tracking and general control of the two radios involved in the solution and so I set about creating a QO-100 Dashboard using the great Node-RED graphical programming environment to create a web app that simplifies the management of the entire setup.

The QO-100 Dashboard synchronises the transmit and receive VFO’s, enables split operation so that you can transmit and receive on different frequencies at the same time and a whole host of other things using very little code. Most of the functionality is created using standard Node-RED nodes. More info on Node-RED can be found on the Opensource.radio Wiki or from the menu’s above.

I’ll be publishing an article all about the QO-100 Dashboard in the very near future along with a downloadable flow file.

I’m extremely pleased with how well the ground station works and have had well in excess of 500 QSO’s on the QO-100 satellite over the last last year.

More soon …

On June 25 the NOAA GOES-U weather satellite was successfully launched on a SpaceX Falcon 9 Heavy rocket. Once it reaches geostationary orbit, this will be a new weather satellite that RTL-SDR hobbyists can receive with an RTL-SDR dongle, satellite dish, and LNA.

From launch, it will take about two weeks for GOES-U to reach geostationary orbit and once it gets there it will be renamed to GOES-19. It is due to be positioned where GOES-16 currently is, and GOES-16 will become the redundant backup satellite. This positioning will make the satellite visible to those in North and South America.

We are anxiously looking forward to the first images from GOES-19 received by hobbyists, but once positioned it will probably take several weeks to be tested and calibrated before hobbyists can receive any signals on L-band. 

Over on X, @WeatherWorks posted a short video showing that the launch plume was visible from GOES-16.

The @CIRA_CSU account has also posted a video from GOES-18 which shows the launch in the water vapor bands

Finally, @SpaceX has also posted a video showing the deployment of the satellite, with an impressive shot showing how far away it is from the Earth.

I had a few tasks to carry out for my club, Newport County Radio Club, during Field Day 2024, which was hazy, hot, and humid (sounds familiar).

I was charged with making a satellite contact, something I had not done since 2020.  I spent two weeks before ensuring that I had calibrated all the satellites that were still in the air (and bemoning all the ones that were no longer available – CAS-x, XW-x, etc.).  My station is shown in the photo below (IC-9700, laptop running SATPC32, and a 3×11 Arrow antenna on a photo tripod).

The first available pass was for RS-44, and would be at the point of closest approach right at 1400 EDT.  With only about 8 minutes to make a contact at that point, I was pretty confident, but imagine my disappointment when I could barely hear any singlas on the satellite and couldn’t hear my downlink at all.  After that failed pass, I did some quick checking and discovered that the VHF and UHF coax cables had been attached to the wrong beam.  EEK!

There was a pass of AO-73 about a half hour later, and I had no trouble making 3 SSB contacts on it (I gave up trying CW as there were no responses other than folks going up and down the band to find themselves sending endless dots and dashes).  A couple of hours later there was a pass of AO-7, and I quickly made a SSB contact on that bird, just to pay homage to the little satellite that still does, 50 years later!

Another task was to pass a section manager message from our site at Glen Park (Portsmouth RI) through a VHF link to my home gateway (WB4SON-10 on 145.050 MHz).  Despite the 21 mile path and some terrain between the two locations, it was an easy S9+++ connection with a full speed data link.  This message was also part of the Winlink Thursday drill for the week before and after Field Day.

As I wrapped up the AO-7 contact, I felt a burst of cool air on my back, a 180 degree change of wind direction.  I suspected there was a downdraft nearby, so I quickly took my equipment apart, stuffed it in my car, and headed home.  A few minutes after I left, the skies opened with a deluge of rain.  I felt sorry for my buddies in various tents still at the site.

When I got home, I copied the W1AW CW bulletin.

My final task was to work the CW station for the final 2.5 hours of the contest on Sunday.  This year I decided to run Search/Pounce, and enjoyed contacts on 10, 15 and 20 meters.

As always, lots of fun

With the help of Derek, V51DM in Namibia I reached 100 DXCC on Greencube IO-117 only. I have no homestation, so this was either done fully battery powered from portable or with my 10 ele Alaskan Arrow antenna handheld. I did my first QSO on Greencube in Feb 2023, so it took roughly 15 months to reach this milestone. GreenCube, also known as Italy OSCAR 117, or IO-117 for short, is an Italian technology testing and amateur radio satellite in 3U-CubeSat format. The project is coordinated by the Italian Space Agency (ASI) and took advantage of a launch opportunity offered by ESA. At the end of the mission, the satellite was recently taken over by AMSAT Italia.

The document attached has all the current FM and Linear Satellite passes during daylight hours for FN41 (Rhode Island)

Field Day 2024 Satellite Passes

I haven’t made a satellite contact in a few years as another club member was nice enough to step up.  However, he had to back out this year, and I was left flat footed when everyone else took a step back; it looked like I had stepped forward to volunteer.

I spent a few hours today updating my satellite laptop with all the latest Windoze stuff, and figuring out why my IC-9700 didn’t power up (12VDC power supply had a loose AC plug).  My next shock was that, for the most part, the birds I used a few years back were no longer active (bye bye CAS-x and XW-X).  AO-7 is still sort of working, as was RS-44.

I was able to adjust the transmitter calibration and hear myself on RS-44, but had no responses to a CQ.  That bird seemed to have very good doppler correction throughout the last half of the pass.

I also heard a few SSB calls on AO-73, so gave that a try.  As usual the transmit doppler correction was about 7000 Hz off.  I did make a partial SSB contact with N2FYA, but I don’t think he had the last letter of my call correct.  AO-73 has always been a challenge for me due to its unpredictable frequency offsets.

I need to setup FO-118, JO-97, HO-113 and XW-4, which are all new birds for me, then get the transmit uplink calibrated for them and AO-7.

Field Day 2024 rules are clear that multiple QSOs count now, but only one FM contact may be counted per FM bird:

7.3.7. Satellite QSO: 100 bonus points for successfully completing at least one QSO via an amateur radio satellite during the Field Day period. “General Rules for All ARRL Contests” (Rule 3.7.2.), (the no-repeater QSO stipulation) is waived for satellite QSOs. Groups are allowed one dedicated satellite transmitter station without increasing their entry category. Satellite QSOs also count for regular QSO credit. Show them listed separately on the summary sheet as a separate “band.” You do not receive an additional bonus for contacting different satellites, though the additional QSOs may be counted for QSO credit unless prohibited under Rule 7.3.7.1. The QSO must be between two Earth stations through a satellite. Available to Classes A, B, and F.

7.3.7.1 Stations are limited to one (1) completed QSO on any single channel FM satellite.

Congratulations to Max, EI6KC on achieving his third CQ Satellite Worked All Zones (WAZ) award. He already holds two SAT WAZ awards as SA5IKN (#40) and M0SKN (#92). His latest SAT WAZ award (#121) is also the first one in Ireland.

In recent years GPS spoofing and jamming have become quite commonplace. Recently popular YouTuber Scott Manley uploaded a video explaining exactly what GPS spoofing and jamming is and explains a bit about who is doing it and why.

In the video Scott explains how aircraft now routinely use GPS as a dominant navigational sensor and how some commercial flights have been suspended due to GPS jamming. Scott explains how ADS-B data can be used to determine the source of GPS jamming (via gpsjam.org) and shows hotspots stemming from Russia. He goes on to show how drone shows have also failed in China either due to GPS jamming by rival companies or due to Chinese military warship jamming. Scott then explains a bit about GPS and how jamming and spoofing work.

Ever since my QO-100 ground station has been operational I’ve been using my NodeRed QO-100 Dashboard to control my IC-705 and GQRX SDR software to drive my NooElec SmartSDR receiver. This gives me a full duplex ground station with both transmit and receive VFO’s synchronised.

This solution has worked incredibly well from the outset and over time I’ve added extra functionality that I’ve found to be useful to enhance the overall setup.

The latest addition to the ground station solution is a Sennheiser Headset that I picked up for just £56 on Amazon (Much cheaper than the Heil equivalents at the HAM stores!) and have found it to be excellent. The audio quality from both the mic and the headphones is extremely good whilst being light and comfortable to wear for extended periods.

To incorporate this into the ground station the headset is connected to my Kubuntu PC and the audio chain to the IC-705 is sent wirelessly using the latest version of WFView. This works extremely well. The receive audio comes directly from the GQRX SDR software to the headphones so that I have a full duplex headset combination.

Audio routing is done via pulse audio on the Kubuntu PC and is very easy to setup.

Since I no longer have a mic connected to the IC-705 directly I found that I needed a way to operate the PTT wirelessly and this is where the latest addition to my NodeRed QO-100 Dashboard comes in.

Adding a little functionality to the NodeRed flow I was able to create a button that toggles the IC-705 PTT state on and off giving me the ability to easily switch between receive and transmit using a simple XMLRPC node without the need for a physical PTT button.

The PTT state and PTT button colour change is handled by the Toggle PTT function node shown in the above flow. The code to do this is relatively simple as shown below.

The entire QO-100 Dashboard flow has grown somewhat from it’s initial conception but, it provides all the functionality that I require to operate a full duplex station on the QO-100 satellite.

This simple but, effective PTT solution works great and leaves me hands free whilst talking on the satellite or the HF bands when using the IC-705. This also means that when using my IC-705 it only requires the coax to be connected, everything else is done via Wifi keeping things nice and tidy in the radio shack.

The image above shows the QO-100 ground station in receive cycle with the RX/TX VFO’s in split mode as the DX station was slightly off frequency to me. The PTT button goes red when in TX mode just like the split button shown above for visual reference.

As you can probably tell, I’m a huge fan of NodeRed and have put together quite a few projects using it, including my HF Bands Live Monitoring web page.

More soon …

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.