❌

Normal view

There are new articles available, click to refresh the page.
Before yesterdayMain stream

Deep Dive – Node-RED QO-100 Satellite Ground Station Dashboard

By: M0AWS
12 June 2024 at 19:25

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.

M0AWS QO-100 ground Station Control Dashboard built using Node-RED.
M0AWS QO-100 Ground Station Control Dashboard built using Node-RED.

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.

M0AWS Node-RED QO-100 Ground Station Dashboard - 12/06/24
M0AWS Node-RED QO-100 Ground Station Dashboard Flow as of 12/06/24

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.

M0AWS - Node-RED QO-100 Ground Station Dashboard - GQRX Startup
M0AWS Node-RED QO-100 Ground Station Dashboard – GQRX Startup Flow

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.

M0AWS - QO-100 Ground Station Dashboard - GQRX RIGCTL flow
M0AWS Node-RED QO-100 Ground Station Dashboard – GQRX RIGCTL Flow

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.

M0AWS - QO-100 Ground Station Dashboard - GQRX Controls
M0AWS Node-RED QO-100 Ground Station Dashboard – GQRX Controls Flow

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.

M0AWS - QO-100 Ground Station Dashboard - Powermate VFO section
M0AWS Node-RED QO-100 Ground Station Dashboard – Powermate VFO Flow

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.

M0AWS - QO-100 Ground Station Dashboard - IC-705 control flow
M0AWS Node-RED QO-100 Ground Station Dashboard – IC-705 Control Flow

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 …

The Matrix HAM Radio Community continues to grow

By: M0AWS
10 June 2024 at 10:12

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.

Global Matrix Ham Radio Space hosted on the M0AWS Matrix Server
Global Matrix Ham Radio Space hosted on the M0AWS Matrix Server

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 …

QO-100 Satellite Ground Station Complete Build

By: M0AWS
5 June 2024 at 14:49

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.

M0AWS QO-100 Ground Station Build Visual
M0AWS QO-100 Ground Station Build Visual (Click to Enlarge)

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
M0AWS QO-100 1.1m off-set Dish and IceCone Helix antenna ground station
M0AWS QO-100 1.1m (110cm) off-set Dish with IceCone Helix antenna and Bullseye LNB.

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.

2.4Ghz ground station enclosure ready for testing
2.4Ghz ground station enclosure ready for testing

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.

Bullseye 10Khz High Stability Unversal Single LNB for 10.489-12.750Ghz
Bullseye 10Khz High Stability Unversal Single LNB for 10.489-12.750Ghz

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.

Bias-T to inject 12v feed into the coax for the Bullseye LNB
Bias-T to inject 12v feed into the coax for the Bullseye LNB

From the Bias-T the coax comes down to the NooElec SmartSDR receiver. This is a really cheap SDR device (<Β£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.

M0AWS QO-100 ground Station Control Dashboard built using Node-RED.
M0AWS QO-100 ground Station Control Dashboard built using Node-RED.

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 …

GOES-U Satellite Launched and on the way to Geostationary Orbit

By: admin
28 June 2024 at 02:31

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.

GOES-16 is where GOES-19 will be positioned.
GOES-16 is where GOES-19 will be positioned.

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.Β 

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

A successful launch of @NOAA's GOES-U satellite yesterday. But was even cooler? It was seen from GOES-16! Check it out. It may be hard to see, but a cloud blips into view on satellite as the @SpaceX falcon heavy rocket as it lifts off from Cape Canaveral. #Space #SpaceX #GOESU… pic.twitter.com/e1s261y797

β€” WeatherWorks (@WeatherWorks) June 26, 2024

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

GOES-U has made it to space and is on its way to geostationary orbit around Earth.

This 30-second imagery from GOES-18 shows the launch and booster separation as seen across all three water vapor bands.

GOES-U will be renamed as GOES-19 once it makes it to geostationary orbit. pic.twitter.com/u9KfRyfdM7

β€” CIRA (@CIRA_CSU) June 26, 2024

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.

Deployment of @NOAA’s GOES-U satellite confirmed pic.twitter.com/Q5CDr6FSaL

β€” SpaceX (@SpaceX) June 26, 2024

Marine Radiofax Weather Charts Via Shortwave Radio – WEFAX

16 June 2024 at 00:53
Weather out over oceans?Β  That, and more. More than international broadcast stations and amateur radio operators exist on the shortwave radio spectrum.Β  For instance, any non-broadcast signal that is not amateur radio is often lumped together into a category known as Utility Radio, abbreviated, UTE.Β  To dig deeper into UTE activity, you could check out […]

So how did Field Day 2024 go for me personally?

By: robert
26 June 2024 at 00:00

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.Β  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.).Β  My station is shown in the photo below (IC-9700, laptop running SATPC32, and a 3Γ—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.Β  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.Β  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.Β  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).Β  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).Β  Despite the 21 mile path and some terrain between the two locations, it was an easy S9+++ connection with a full speed data link.Β  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.Β  I suspected there was a downdraft nearby, so I quickly took my equipment apart, stuffed it in my car, and headed home.Β  A few minutes after I left, the skies opened with a deluge of rain.Β  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.Β  This year I decided to run Search/Pounce, and enjoyed contacts on 10, 15 and 20 meters.

As always, lots of fun

100 DXCC reached only on Greencube IO-117 SAT

8 May 2024 at 12:35

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.

Marine Radiofax Weather Charts Via Shortwave Radio – WEFAX

16 June 2024 at 00:53
Weather out over oceans?Β  That, and more. More than international broadcast stations and amateur radio operators exist on the shortwave radio spectrum.Β  For instance, any non-broadcast signal that is not amateur radio is often lumped together into a category known as Utility Radio, abbreviated, UTE.Β  To dig deeper into UTE activity, you could check out […]

Getting Ready For Field Day Satellite

By: robert
7 June 2024 at 20:21

I haven’t made a satellite contact in a few years as another club member was nice enough to step up.Β  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).Β  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).Β  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.Β  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.Β  As usual the transmit doppler correction was about 7000 Hz off.Β  I did make a partial SSB contact with N2FYA, but I don’t think he had the last letter of my call correct.Β  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:Β 100 bonus points forΒ successfully completing at least one QSOΒ via anΒ amateur radio satellite during the Field Day period. β€œGeneralΒ Rules for All ARRL Contests” (RuleΒ 3.7.2.), (the no-repeater QSO stipulation) is waived for satellite QSOs. Groups are allowed oneΒ dedicated satellite transmitter station without increasing their entry category. Satellite QSOs alsoΒ count for regular QSO credit. Show them listed separately on the summary sheet as a separateΒ β€œband.” You do not receive an additional bonus for contacting different satellites, though theΒ additional QSOs may be countedΒ for QSO credit unless prohibitedΒ under Rule 7.3.7.1. The QSOΒ must be between two Earth stations through a satellite.Β 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.

Scott Manley Explains GPS Jamming & Spoofing and Why & Who is Causing It

By: admin
15 May 2024 at 03:55

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.

YouTube Video

Update to my NodeRed QO-100 Dashboard

By: M0AWS
13 May 2024 at 10:59

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 Β£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.

M0AWS - Sennheiser SC 165
M0AWS – Sennheiser SC 165 Headset

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.

M0AWS - Additional NodeRed PTT Flow
M0AWS – Additional NodeRed PTT Flow

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.

M0AWS - NodeRed Toggle PTT Function to change button colour
M0AWS – NodeRed Toggle PTT Function to change button colour

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.

M0AWS - NodeRed QO-100 Dashboard complete flow
M0AWS – NodeRed QO-100 Dashboard complete flow

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.

M0AWS - Updated NodeRed QO-100 Dashboard with PTT button
M0AWS – Updated NodeRed QO-100 Dashboard with PTT button

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 …

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

By: admin
13 May 2024 at 03:35

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.

YouTube Video

Newfoundland QO-100 Contact Successful – More Planned

By: Editor
12 May 2024 at 09:17
First Newfoundland contact via QO-100 between VO1/M0XUU and G0MRF

First Newfoundland contact via QO-100 between VO1/M0XUU and G0MRF

On Saturday, May 11, 2024, Gopan VO1/M0XUU (VU3HPF) succeeded in making the first contact from North America through the amateur radio QO-100 geostationary satellite transponder located at 26Β° East.

Gopan's Screenshot of First Newfoundland QO-100 Contact

Gopan’s screenshot of first Newfoundland QO-100 contact

Gopan was in Newfoundland which is just outside the coverage area of QO-100, the elevation at Signal Hill at St. Johns is below the horizon at -0.9Β°.

He used FT-8 to have a trans-atlantic contact with David G0MRF in south-west London. David reported it was tough going with a lot of QSB.

Gopan will be in Newfoundland until May 15.

In a post on X Gopan reported his signal into QO-100 was not strong enough to permit SSB operation.

Dish used by VO1/M0XUU in Newfoundland

Dish used by VO1/M0XUU in Newfoundland

The transmit equipment Gopan used comprised, ICOM IC-705 with 2.4 GHz Up-converter from DX Patrol, feeding a homemade 2.4 GHz amplifier delivering 10 watts output to a Helix 2.5 turn YATT design.

The receive side comprised a homemade 10 GHz Down-converter was based on a design by David G0MRF, a modified LNB all controlled by a Leo Bodnar M0XER GPSDO.

The dish was an 80 cm offset.

The software used was SDR Console and Airspy for setting up the station and MSHV in standard mode for FT8/FT4.

After his initial contact with David G0MRF, Gopan went on the work several other stations including Sadan TA4SO in Turkey.

David G0MRF will be joining Graham G3VZV on a QO-100 Dxpedition to Newfoundland from May 15-19.

They are taking enough equipment to enable transmissions on QO-100 using SSB / CW / FT8 / FT4 / Digital Amateur Television (DATV).

Graham G3VZW testing QO-100 equipment before Newfoundland Dxpedition with David G0MRF

Graham G3VZW testing QO-100 equipment before Newfoundland Dxpedition with David G0MRF

A video of the presentation β€˜Making QO-100 contacts from North America – A new challenge’, given by Graham G3VZV at the 2022 AMSAT-UK Colloquium can be seen at
https://amsat-uk.org/2022/11/01/making-qo-100-contacts-from-north-america-a-new-challenge/

AMSAT-UK issue a special Certificate of Achievement for QO-100 contacts made from North America.Β  Applications should be sent to awards@amsat-uk.org

Full details of the award in this Word Document

QO-100 North America CertfificateYou can follow posts on X at:

Gopan M0XUU – https://X.com/vu3hpf
David G0MRF – https://X.com/g0mrf
Graham G3VZV – https://X.com/G3VZV

Stefan VE4SW reports he will be traveling to Newfoundland and will be using the callsign VO100QO on QO-100 from May 13-17, he writes:

β€œVO100QO a special callsign for the activation of QO-100 from St John’s in Newfoundland will be used by the β€œAmateur Radio Satellites and Systems – Canada” Association starting Monday, May 13, at Signal Hill or another suitable location (weather permitting). Canadian amateur radio operators Stefan Wagener VE4SW and John Langille VE1CWJ will use a 1.8m dish and up to 100W on SSB to reach QO-100 at -1 degree elevation.

We invite all stations and operators in or near St John’s to join us in person and be part of the story. We will operate from Monday, May 13th to Friday, May 17th (weather permitting). Contact VE4SW (email on my QRZ page) for local information and timing.

The β€œAmateur Radio Satellites and Systemsβ€”Canada” Association will issue special certificates for successful contacts, and all QSOs will be logged into LoTW. Please see our β€œVO100QO” QRZ page for updates starting Sunday, May 12.

We would very much like to acknowledge the support of β€œDX Patrol” in Portugal (https://dxpatrol.pt) and AntΓ³nio Matias for his support. We will use the DX Patrol QO-100 Groundstation V2 and other equipment for our attempt!”

Follow Stefan VE4SW on X – https://X.com/StefanWagener3

Information on QO-100 is at https://forum.amsat-dl.org/index.php?board/3-qo-100-es-hail-2-p4-a/

FT-8 QO-100 contact between Gopan VO1/M0XUU and TA4SO

FT-8 QO-100 contact between Gopan VO1/M0XUU and TA4SO

Newfoundland on QO-100 ?

By: Editor
5 May 2024 at 12:59

QO-100 North America CertfificateDuring May there are plans for two separate attempts to make contacts from Newfoundland using the QO-100 geostationary satellite amateur transponders.

Newfoundland is just outside the coverage area of QO-100, the elevation at Signal Hill at St. Johns is -0.9Β°, however, contacts have been made from Indonesia at an elevation as low as -1.3Β° so there is a chance of success.

Gopan VO1/M0XUU (VU3HPF) will be in Newfoundland from May 8-15 and will attempt to make QO-100 contacts.

David VO1/G0MRF and Graham VO1/G3VZV will be in Newfoundland May 15-19 and plan to be active on QO-100 using SSB / CW / FT8 / FT4 / DATV.

You can follow posts on X at:

Gopan M0XUU – https://X.com/vu3hpf
David G0MRF – https://X.com/g0mrf
Graham G3VZV – https://X.com/G3VZV

Video of the presentation β€˜Making QO-100 contacts from North America – A new challenge’, given by Graham G3VZV at the 2022 AMSAT-UK Colloquium
https://amsat-uk.org/2022/11/01/making-qo-100-contacts-from-north-america-a-new-challenge/

Information on QO-100 is at https://forum.amsat-dl.org/index.php?board/3-qo-100-es-hail-2-p4-a/

Gypsum: A Software-Defined GPS Receiver written in Python + A Writeup on How it Was Made

By: admin
18 April 2024 at 04:09

Thank you to RTL-SDR.COM reader Lee. who found a recently released program called "gypsum" which enables an RTL-SDR or HackRF to be used as a GPS Receiver when combined with a GPS antenna. Phillip Tennen, the author of Gypsum notes that Gypsum can obtain a fix within 60 seconds from a cold start and that it has no dependencies apart from numpy. We want to note that it appears that Gpysum has no live decoding ability yet, as it works from pre-recorded GNU Radio IQ files.

In the past, we've shown in a tutorial how GPS can be received and decoded with GNSS-SDRLIB and RTKLIB on Windows. The new Gypsum software should work on Linux and MacOS too.

What's more, Phillip has written an incredible 4-part writeup on how Gypsum was implemented from scratch. In the write-up, Phillip introduces GPS and explains how it can even work with such weak signals that appear below the thermal noise floor. He then goes on to explain how the detected signal is decoded and turned into positional information, and how challenging it was to propagate the accurate timing information that calculating a solution requires. The write-up is presented with clear visualizations to help readers intuitively gain an understanding of the advanced concepts involved.

Gypsum GPS Satellite Tracking Dashboard GUI
Gypsum GPS Satellite Tracking Dashboard GUI

Building HAM Clock on an old RaspberryPi

By: M0AWS
10 April 2024 at 18:05

I’ve got a couple of old RaspberryPi computers on the shelf in the shack and so decided it was time for me to put one of them to good use. The first model on the shelf is the oldest and is one of the very first RaspberryPi 1 computers that was released. (It’s the one with the yellow analog video signal output on the board!). This particular model is extremely slow but, I hang onto it just as a reminder of the first SBC in the line.

The second one is a RaspberryPi 2, a quad core machine that is only slightly faster than the first model but, it’s powerful enough to run HAM Clock.

It didn’t take long to install a vanilla Raspbian Desktop O/S and get it configured on the local LAN. I installed a few packages that I like to have available on all my Linux machines and then started on the HAM Clock install.

The first thing I needed to do was install the X11 development library that is required to compile the HAM Clock binary. To do this, open a terminal and enter the command below to install the package.

sudo apt install libx11-dev

You will need to type in your password to obtain root privileges to complete the installation process and then wait for the package to be installed.

The HAM Clock source code is available from the HAM Clock Website under the Download tab in .zip format. Once downloaded unzip the file and change directory into the ESPHamClock folder ready to compile the code.

cd ~/Downloads/ESPHamClock

Once in the ESPHamClock directory you can run a command to get details on how to compile the source code.

make help

This will check your system to see what screen resolutions are available and then list out the options available to you for compiling the code as shown below.

The following targets are available (as appropriate for your system)

    hamclock-800x480          X11 GUI desktop version, AKA hamclock
    hamclock-1600x960         X11 GUI desktop version, larger, AKA hamclock-big
    hamclock-2400x1440        X11 GUI desktop version, larger yet
    hamclock-3200x1920        X11 GUI desktop version, huge

    hamclock-web-800x480      web server only (no display)
    hamclock-web-1600x960     web server only (no display), larger
    hamclock-web-2400x1440    web server only (no display), larger yet
    hamclock-web-3200x1920    web server only (no display), huge

    hamclock-fb0-800x480      RPi stand-alone /dev/fb0, AKA hamclock-fb0-small
    hamclock-fb0-1600x960     RPi stand-alone /dev/fb0, larger, AKA hamclock-fb0
    hamclock-fb0-2400x1440    RPi stand-alone /dev/fb0, larger yet
    hamclock-fb0-3200x1920    RPi stand-alone /dev/fb0, huge

For my system 1600Γ—960 was the best option and so I compiled the code using the command as follows.

make hamclock-1600x960

It’s no surprise that it takes a while to compile the code on such a low powered device. I can’t tell you how long exactly as I went and made a brew and did a few other things whilst it was running but, it took a while!

Once the compilation was complete you then need to install the application to your desktop environment and move the binary to the correct directory.

make install

Once the install is complete there should be an icon on the GUI desktop to start the app. If like mine it didn’t create the icon then you can start the HAM Clock by using the following command in the terminal.

/usr/local/bin/hamclock &

The first time you start the app you’ll need to enter your station information, callsign, location etc and then select the settings you want to use. There are 4 pages of options for configuring the app all of which are described in the user documentation.

M0AWS - HAM Clock running on RaspberryPi Computer
M0AWS – HAM Clock running on RaspberryPi Computer

Once the configuration is complete the map will populate with the default panels and data. I tailored my panels to show the items of interest to me namely, POTA, SOTA, International Beacon Project and the ISS space station track. I was hoping to be able to display more than one satellite at a time on the map however, the interface only allows for one bird to be tracked at a time.

You can access the HAM Clock from another computer using a web browser pointed at your RaspberryPi on your local LAN using either the IP address or the hostname of the device.

http://<hostname>:8081/live.html

or

http://<ip-address>:8081/live.html

You can also control the HAM Clock remotely via web browser using a set of web commands that are detailed on port 8080 of the device.

http://<hostname or ip-address>:8080/

M0AWS - HAM Clock remote command set
M0AWS – HAM Clock remote command set

This is a great addition to any HAM shack especially if, like me you have an old HDTV on the wall of the shack that is crying out to display something useful.

More soon …

Testing a WiFi Grid Antenna for L-Band Satellites

By: admin
9 April 2024 at 05:13

Over on YouTube dereksgc has uploaded a video where he tests out a 2.4 GHz WiFi Grid antenna for L-band weather satellite reception. WiFi grid antennas are typically repurposed in the SDR community for L-Band weather satellite reception because they are cheap and mostly work out of the box. They can also be used for hydrogen line radio astronomy. TV dish antennas are an alternative but with them, a custom feed needs to be built.Β 

In his video, dereksgc tests the WiFi dish on receiving various polar-orbiting L-band satellites including Metop, and Meteor M2. With the polar orbiting satellites the dish needs to point at the satellite as it passes over the sky and so dereksgc recommends using a mount if hand tracking them.

Later in the video he tests some geostationary satellites but finds that the dish is not tuned well enough to receive Elektro-LN3 properly without modifications. He was however able to receive a noisy image from FengYun-2H successfully.

We note that we also currently have our Discovery Dish product available for pre-order, which is similar to the WiFi grid dish, but smaller and lighter weight with a built-in optimized active feed.

YouTube Video

❌
❌