grid.radio is a web application born out of the frustration that Rose, 2E0RXO and many others experienced during spontaneous, often unplanned, Parks on the Air activations. During busy moments, someone would inevitably ask for a Worked All Britain square or another reference that she wasn’t prepared for. There wasn’t a single, simple resource to quickly […]

The next meeting of Aberdare and District Amateur Radio Society will be held on Friday 11 October at Hirwaun YMCA Hall, CF44 9RB from 6pm. Ian Miles 2W0IWM, info@aberdareradio.club Aberkenfig and District Amateur Radio Club has its weekly meeting on Wednesday from 7pm at Tondu Railway Club, Station Approach, Bridgend. The club is an approved […]

The theme for the 2024 RSGB Convention is Your Convention, your way and the Society is providing a range of activities and presentations as well as different ways to get involved. There is still just time to buy your tickets in advance, but hurry as advance sales for attending the Convention or the dinners close […]

Did you take part in National Coding Week this year? The RSGB had nine activities to inspire you to take part, including two new worksheets developed by the Society’s Outreach Team. Whether you took part by yourself, at a club night, or with friends and family, the RSGB would love to hear from you. To […]

The next RSGB Tonight @ 8 live webinar is on Monday 7 October 2024 when Ian White, GM3SEK presents Aircraft Scatter, the Hitch-Hikers Guide. Aircraft scatter is about bouncing VHF and UHF radio signals off high-flying aircraft—effectively ‘hitching a ride’ with someone else’s plane to extend your everyday working range up to 800km. It may […]

At 11:29 GMT on Saturday October 5, 2024, an Amateur Radio on the International Space Station (ARISS) radio contact between astronaut Sunita Williams KD2PLB aboard the International Space Station (ISS) and members of Girlguiding Surrey West County, took place at the Brooklands Museum and Brookland Innovation Academy, located in Weybridge, UK.

ARISS conducts 60-100 of these special Amateur Radio contacts each year between students around the globe and crew members with ham radio licenses aboard the ISS.

Watch the recording at https://live.ariss.org/

Girlguiding Surrey West is a charity organization for girls and young women. Girlguiding wants to inspire their members to learn skills in science, technology, engineering and math with fun guiding activities and science-based activities. The Brooklands Innovation Academy, established in 2022, creates inspirational STEM experiences for young people. The age range of the participants for this ARISS contact are 5 to 19 years old. By hosting this ARISS contact they are also demonstrating real-world application of STEM concepts (an important principle at Brooklands Museum) to space missions and are encouraging the girls to complete their space interest badge. The group is being supported by the Radio Society of Great Britain and the ARISS UK Team to establish the radio link.

Girlguiding patron, Her Royal Highness The Duchess of Edinburgh attended the contact to help in promoting the engagement and involvement of girls and young women in STEM. She greeted Sunita Williams on board the IS

This was a direct contact via Amateur Radio allowing students to ask their questions of astronaut Sunita Williams, amateur radio call sign KD5PLB. The downlink frequency for this contact was 145.800 MHz and was heard by listeners within the ISS-footprint that also encompasses the relay ground station.

The amateur radio ground station for this contact is in Weybridge, UK. Amateur radio operators using call sign GB4GGB, operated the ground station to establish and maintain the ISS connection.

The recording of the live stream isat: https://www.youtube.com/watch?v=lxN4VuNj_AY

_______________________________

As time allows, students will ask these questions:

1. Who or what inspired you to become an astronaut and what advice would you have for any of these girls here today who might want to become an astronaut?

2. Do you have any free time and if so what do you spend your time doing?

3. There are many international time zones so how does time work on the ISS?

4. If you were not an astronaut, what job would you like to have instead?

5. What things do you like to take with you to remind you of home?

6. What is the hardest part of your job?

7. How does the food and drinks do you have in space compare to foods on earth?

8. What do you miss about Earth?

9. How long have you been on the international space station?

10. What was your reaction when you found out you had been selected to fly to the ISS?

11. What stars or other things have you seen in space?

12. Is space hot or cold?

13. Does space smell of anything?

14. How do you sleep in space?

15. What is your favorite planet and why?

16. Have you done a spacewalk? If so, what was it like?

17. The spacesuits look very heavy, are they uncomfortable to wear?

18. What is it like floating in space? Have you ever lost anything from it floating away?

19. What things do you like to take with you to remind you of home?

About ARISS:

Amateur Radio on the International Space Station (ARISS) is a cooperative venture of international amateur radio societies and the space agencies that support the ISS. In the United States, sponsors are the American Radio Relay League (ARRL), Amateur Radio Digital Communications (ARDC), Radio Amateur Satellite Corporation (AMSAT), NASA’s Space Communications and Navigation program (SCaN) and the ISS National Lab—Space Station Explorers. The primary goal of ARISS is to promote exploration of science, technology, engineering, the arts, and mathematics topics. ARISS does this by organizing scheduled contacts via amateur radio between crew members aboard the ISS and students. Before and during these radio contacts, students, educators, parents, and communities take part in hands-on learning activities tied to space, space technologies, and amateur radio. For more information, see http://www.ariss.org/

Follow ARISS on X at https://x.com/ARISS_Intl

Those satellite enthusiasts thinking of getting their UK Amateur Radio licence may like to know a Free online training courses are available at http://hamtrain.co.uk

In what is believed to be a UK first, there was an aeronautical mobile entry in the RSGB 144 MHz FM contest on 3 September. Nick Long and Amy Whitewick operated G4BIN/AM from Nick’s Beagle Pup aircraft. The aircraft has been fitted with monopole antenna tuned to 144 MHz and a temporary mount for an IC-705. […]

The Radio Society of Great Britain and ARISS, in conjunction with Girlguiding Surrey West and Brooklands Museum including the Innovation Academy, have been collaborating on a special ISS contact due to take place on Saturday 5 October. Girlguiding Patron, HRH The Duchess of Edinburgh will attend the contact as part of a visit to promote […]

[John Calhoun] was digging around their old MAC hard drives, revisiting some abandoned shareware games...

As the technology available to the average hacker and maker gets better and cheaper each...

Ian White gives the following diagram to explain what goes on at the coax to dipole junction.

He labels five currents in his explanation.

Let’s simplify that

Above is a diagram from Common mode current and coaxial feed lines showing the currents where a coax connects two two wires.

Lets morph that to the dipole feedpoint topology.

The whole thing is defined by just two currents, I1 and I2. The common mode current Ic=I1-I2. There is common mode current present in the short two wire connection to the dipole, and on the outer surface of the coaxial cable.

Note that I1, I2 and Ic are usually standing waves (ie they vary with location), and so these currents are defined here at the point where the conductors meet the end of the coax.

Are the currents measurable?

Using a clamp on RF current probe, the currents on the each of the two dipole conductors I1 and I2 is measurable, and so also the current on the outside surface of the coax shield Ic.

Remember also that these are sinusoidal AC currents, and I1, I2 and Ic refer to the magnitude of the currents.

The three currents can be resolved into the common mode and differential components, see Resolve measurement of I1, I2 and I12 into Ic and Id
(I12=Ic, the current measured with the probe around both two wire conductors or around the outside of the coax.

Can the currents be measured at an elevated dipole feed point?

Sure. I have done measurements of Ic over the length of coax by hoisting a current probe on a separate halyard to raise and lower it and reading it from the ground with a spotting scope.

Recall that Ic is usually a standing wave, and when you measure it at just one point, you don’t know much about it.

Thanks to Rogier PA1ZZ for sending me this YouTube link.  It is a truly wonderful channel from Spain. Not only the Collins Gold Dust Twins, but also lots of great (and not-so-great!) older receivers.  SP-600s, S-38s,  Rhode and Schwartz rigs, lots of great stuff.  Go to the "Videos" link and enjoy the Thermatron goodness.   Thanks Rogier!  And thanks Fernando! 

 https://www.youtube.com/@jonglei

AMSAT-UK is delighted to have been able to accept an opportunity to provide a FUNcube Lite payload, with a mode U/V FM transponder, for the exciting Jovian-1 satellite.

This 6U CubeSat is being designed and built by Space South Central which is the largest regional space cluster in the UK.

This is a partnership between industry and academia, designed to accelerate space business growth, grow the reputation

of the south central region of the UK and foster an environment of innovation.

A collaboration between the universities of Surrey, Portsmouth and Southampton, JUPITER – the Joint Universities Programme for In-Orbit Training, Education and Research – will equip participants with invaluable hands-on space industry experience and training for their future careers.

The FUNcube Lite payload from AMSAT-UK will collect and send telemetry from Jovian-1 sub-systems for educational outreach to schools and colleges, using the tried and tested FUNcube data format.

Telemetry will include data from the payload’s own radiation sensor, along with GPS information gathered from the satellite’s CAN bus.

These data can be used to map radiation throughout the orbit, identifying planetary radiation ‘hotspots’ such as the polar regions and the South Atlantic Anomaly. It will also give an accurate measure of how much radiation reaches the sensitive electronics within the satellite.

While Jovian-1 and its ground station at Surrey University will use commercial S and X band for primary communication,

FUNcube Lite will use frequencies in the amateur UHF and VHF spectrum.

When not sending telemetry, the payload can be configured as a mode U/V FM voice transponder for amateurs to use for international communications.

More information will be provided during the AMSAT-UK Colloquium taking place during the weekend October 12/13th https://amsat-uk.org/colloquium/

Links:
Space South Central: https://www.spacesouthcentral.com/
Surrey University: https://www.surrey.ac.uk/
Portsmouth University: https://www.port.ac.uk/
Southampton University: https://www.southampton.ac.uk/

Dave Johnson, G4DPZ
Hon Sec AMSAT-UK
on behalf of the AMSAT-UK Committee & FUNcube Team

Wow... it's been way too long since my last post on this blog.

Disclaimer - In what I’m describing in this post, to avoid any confusion that I’m trying to claim that any of this involves Amateur Radio, I decided to call this experiment Meadow Day (1). 

Meadow Day 2023 Experiment - Overview

In Zero Retries 0104 Request to Send, Starlink Field Day? I mentioned casually:

Now that I’m a Starlink customer, I consider communications with little terrestrial infrastructure required to be a mostly solved problem, especially when you factor in the increasingly capable battery plus solar units providing power. The combination of the Starlink hardware, battery plus solar, and Starlink subscription isn’t cheap… but it’s amazingly capable… in fact, a paradigm change. But that’s a story for a future issue of Zero Retries. Teaser - Imagine an app that ran on a laptop or Raspberry Pi that connected to another (roaming) Starlink terminal (on battery power), transferred a large file, and then “logged the contact”?

As I woke up yesterday morning (2023-06-24), I thought briefly about ARRL Field Day (2). Because of recent family events, I haven’t been able to devote much time to preparation for Field Day activities, and couldn't devote the entire day to attending a local Field Day event. But I did have a few hours… and the idea came to me fully formed, that I actually could try out “Starlink Field Day” as a proof of concept. I decided that the goal would be to "work" a few Amateur Radio Operators using broadband Internet connectivity via Starlink.

Again - to avoid any confusion that what I'm describing here involves Amateur Radio, I decided to call this experiment Meadow Day. 

Right after morning coffee time I assembled the various pieces I would need and hauled them out of N8GNJ Labs into the middle of my large yard, and started plugging them all together. To my delight… but not quite surprise, it all worked.

What I wanted to test out was, was it practical to “deploy” a Starlink system in “emergency” conditions - on battery power? Short answer, Yes. Even though it was overcast, the solar panel output at least 20 watts, and when there were “widely scattered sunbursts” the solar panel put out as much as 80 watts. The Starlink required typical 60 watts, so the battery on the EB3A trended down slowly.

It worked surprisingly well. I recorded the notes for this post using the temporary Starlink connection as described, and completed the post with the "expedient" Starlink connection that is my sole Internet connectivity in N8GNJ Labs and my office.

Major elements of my Meadow Day "station:

• Starlink terminal - Starlink antenna (Dishy McFlatface), Starlink indoor unit (power supply / Wi-Fi access point), and the Starlink Ethernet adapter.
• Bluetti EB3A battery / power supply
• Generic 100 watt solar panel
• Cisco VOIP telephone (acquired as surplus)
• Macbook Air laptop with USB headset
• Table, chair, beverage, logging sheet

Similarities with Field Day:

• Simulate emergency conditions such as loss of power and other infrastructure.
• Communicate using only what you can carry or transport.
• Set up a communications facility (station) independent of existing communications infrastructure. While it's allowed in the Field Day rules to use an established Amateur Radio station, the intent is "get out into the field" to set up a temporary communications facility (which is what I chose to do for Meadow Day).
• Communicate "out of region" to bypass assumed loss of local communications infrastructure.
• Have fun doing so.

Differences with Field Day:

• I had no desire to accumulate contacts for "points" or other aspects of the overall contest structure of Field Day.
• I was only going to operate for a few hours.
• Field in my case was my house's yard, which is ~ 1 acre.
• Meadow Day was going to use technology of 2023 - Starlink, laptop, VOIP telephone, video conferencing, and a portable battery bank being charged with a solar panel.

 

Meadow Day 2023 Experiment - Photos

Basics of Meadow Day:

• Set up portable table and a camp chair
• Set up solar panel supplying power to portable battery bank
• Set up Starlink terminal in the yard (remote from the desk)
• Set up VOIP phone (connect to Ethernet adapter on Starlink)
• Set up laptop (connect to Starlink Wi-Fi)
• Connect to a number of friends using various videoconference systems (as the most demanding test of broadband capability).

 

N8GNJ Operating Position for Meadow Day 2023
Photo by Tina Stroh KD7WSF

 

N8GNJ Operating Position Desktop 1
Photo by Steve Stroh N8GNJ

 

N8GNJ Operating Position Desktop 2
Photo by Steve Stroh N8GNJ

 

Bluetti EB3A Display (poor visibility in direct sunlight)
Photo by Steve Stroh N8GNJ

 

Generic 100 Watt Solar Panel
Photo by Steve Stroh N8GNJ

The solar panel was casually positioned, leaning on a corner of the table. It was not optimized for angle or orientation, and it was a bit overcast. I have verified that in direct sunlight, it does generate the rated 100 watts (~12 Volts @ ~8.3 Amps). 

 

Bluetti EB3A Status via iPhone App (via Bluetooth)
Screenshot by Steve Stroh N8GNJ

 

Cisco VOIP Phone Configuring Itself
Photo by Steve Stroh N8GNJ

Funny story about this Cisco VOIP phone... I bought a small lot of these from someone six months to a year ago. I just grabbed this one out of the bin I had stored them in, and intended this to be just a "prop" for this story. For fun, because I had an Ethernet port available, I plugged it in. To my amazement, it connected to the host system (that this phone was removed from) and configured itself! I picked up the handset and got a "dialtone" (which was likely generated internally by the phone) and then dialed a couple of digits, and it worked. Not only were these phones not wiped of their configuration, but these phone's MAC addresses apparently weren't deleted from the host system. I'm sure that I could have dialed out with this phone, but I didn't want any accusation of "hacking" the host system. But it was obvious that VOIP works completely normally with Starlink.

 

Starlink Power Supply and Wi-Fi Access Point
Photo by Steve Stroh N8GNJ

 

Dishy McFlatface "deployed" (oriented Northwest)
Photo by Steve Stroh N8GNJ

This is the stand that each Dishy McFlatface (yes, that's the actual product name) is shipped with. It's intended as a starter as Starlink works best with an unobstructed view of the sky, which generally dictates a roof or tower mount. I was lucky that I have a large yard with few tall obstructions.

 

Approximate view of the sky of Dishy McFlatface. Note minor tree obstruction at bottom.
Photo by Steve Stroh N8GNJ

 

Starlink Status (1) via iPhone App (via Wi-Fi)
Screenshot by Steve Stroh N8GNJ

Note that the phone is in Airplane mode - Wi-Fi connectivity only.

 

Starlink Status 2 via iPhone App (via Wi-Fi)
Screenshot by Steve Stroh N8GNJ

For approximately the first 24 hours of operation, in a combination of downloading data from the Starlink satellites, trying different azimuth / elevation settings (Dishy has both attitude and rotational motors, though they're rarely used), and and observing outages with various satellites, Dishy will eventually orient itself to provide optimum connectivity. My Dishy orients itself to the Northwest where there are few obstructions.

 

Meadow Day 2023 Experiment - Contacts

One goal of Meadow Day was to utilize a number of different videoconference systems. Like almost all broadband Internet access systems (other than fiber), Starlink prioritizes downlink speeds over uplink speeds, so it was an interesting test to see if the various videoconference systems would work acceptably on Starlink, especially in this ad-hoc quick setup.

Prior to recording the following screenshot images, I verbally asked each participant for their permission to record a screenshot, and all agreed.

Contact 1 - Cale Mooth K4ACK via (Google Gmail) email

My first Meadow Day contact was to Cale Mooth K4ACK to try to set up a "contact", but he was busy and replied back to me later in the day. But his reply confirmed that there were no issues in using email via Starlink even with the quick setup.

 

Contacts 2 and 3 - Ken Koster N7IPB (left) and Bruce Miller KC7IAY (right) via Jitsi videoconference

Screenshot image recorded by Steve Stroh N8GNJ

Neither N7IPB or KC7IAY noted any issues with my video or audio quality.

 

Contact 4 - Merideth Stroh KK7BKI via Apple Facetime videoconference

Screenshot image recorded by Steve Stroh N8GNJ

KK7BKI didn't note any issues with my video or audio quality.

 

Contact 5 - Budd Churchward WB7FHC via Zoom videoconference

Screenshot image recorded by Steve Stroh N8GNJ

WB7FHC didn't note any issues with my video or audio quality.

WB7FHC recorded the video of our 26 minute conversation. We did a brief overview of what I was trying to accomplish with Meadow Day.

Video link My thanks to WB7FHC for editing our video conversation to a watchable 9 minutes.

 

Contact 6 - Steven Roberts N4RVE via Facebook Messenger videoconference

Screenshot image recorded by Steve Stroh N8GNJ

N4RVE didn't note any issues with my video or audio quality.

 

Contact 7 - Bill Vodall W7NWP via Signal videoconference

Screenshot image recorded by Steve Stroh N8GNJ

W7NWP didn't note any issues with my video or audio quality.

 

Contact 8 - Dewayne Hendricks WA8DZP via Signal videoconference

Screenshot image recorded by Steve Stroh N8GNJ

WA8DZP didn't note any issues with my video or audio quality.

 

Completed N8GNJ Meadow Day 2023 Logsheet.
Photo by Steve Stroh N8GNJ

 

Meadow Day 2023 Experiment - Conclusions

What was remarkable about my experience with Meadow Day 2023... was how unremarkable the experience was.

The Bluetti EB3A portable battery / inverter unit with the 100 watt solar panel just worked to provide AC power to operate the Starlink terminal and Cisco VOIP phone. I connected my laptop to the EB3A's USB-C port to charge it (that cost a bit of battery power). If the day had not been cloudy (direct sunlight) the solar panel would have provided a surplus of power.

When using Starlink as an emergency communications system, it's impressive just how plug and play Starlink is:

• Pull everything out of the box,
• A bit of minor mechanical assembly,
• Connect the cables,
• Place Dishy so that it can see the (as unobstructed as possible) sky (avoiding pointing at obstructions like trees will get online faster),
• Apply power to the router,
• Do a bit of configuration (name, password) in the phone app (only required for the initial setup),
• And… done! Online (via Wi-Fi) at broadband Internet speeds.

Within two minutes of powering up the Starlink, it was providing a broadband Internet connection. I cheated just a little bit knowing that in my area, Dishy McFlatface "prefers" to be facing Northwest, so I saved a bit of time by placing it in that orientation.

To be online at broadband speeds, capable of doing realtime video at reasonable quality, using no local infrastructure, required perhaps fifteen minutes of setup.

Could be better:

• The Bluetti EB3A, rated at 268 Wh (Watt Hours) was probably inadequate for extended operation (with no solar input) of the loads of:
  • Starlink terminal
  • VOIP phone (AC power adapter)
  • Laptop charging / operation
  • Small light (for nighttime operation)
  • Incidental charging - phone, etc.
• Newer, slightly more expensive solar panels are larger (provides more power), flexible, and lighter.

I deem "Meadow Day 2023" a success!

 

Notes:

(1) I didn't want there to be any confusion that my experiment had anything to do with Field Day, thus I created the title "Meadow Day".

(2) The Field Day event held during the Summer is ARRL Field Day. There is also Winter Field Day that is independent of ARRL.

 

Note - This post was actually completed and posted on 2023-10-16, but it will appear in the blog timeline as 2023-06-25, when I should have written and posted it.

Ever since I started using Node-RED I’ve been using the standard node-red-dashboard set of user interface (UI) nodes to build my numerous dashboards to enhance my radio hobby and add new functionality to the operating of the station. The series of UI nodes are very simple to use and have served me well however, they are no longer being developed and are now deprecated in the overall Node-RED project.

To this end flowfuse.com have stepped up to the mark and developed Dashboard 2.0. This new series of UI nodes brings a new, more modern look and feel to the Node-RED dashboard along with some new functionality.

I’ve only just started investigating Dashboard 2.0 but, it’s proving to be fairly easy to use. The short video clip above shows an S-Meter display developed using Dashboard 2.0 for my FTDX10 transceiver.

Full instructions on how to install and configure Node-RED Dashboard 2.0 can be found on the flowfuse.com website.

Be aware though, Node-RED dashboards developed using Dashboard 1.0 will not work under Dashboard 2.0, you will have to import the old v1.0 flow(s) and manually go through them and change all the UI nodes to new Dashboard 2.0 nodes. Since some of the new nodes work differently to the old nodes you’ll also find you will need to make code changes to get the same/similar functionality.

I’m finding it easier not to import old flows but to recreate them afresh under Dashboard 2.0 using the old flow version for reference.

Overtime I will migrate my dashboards over to the new 2.0 version however, this is going to be a lot of work, especially in the case of my QO-100 Ground Station Dashboard as it contains a considerable number of UI nodes, and will take a fair amount of time to migrate.

I’ll document my findings as I go as I’m sure there will be a few trials and tribulations along the way.

Thanks to Neil, G7UFO for pointing me to the new Dashboard 2.0 information.

More soon …

The October 2024 edition of RadCom includes an article about the very first two-way radio communication between the UK and New Zealand, something that Sir Edward Appleton—radio physicist and Nobel laureate—later described as “probably the most dramatic moment in the history of the development of the short waves.” The contact was between two radio amateurs, […]

With just two weeks until the RSGB Convention, this year’s event is the place to go if you are interested in anything and everything to do with amateur radio. There will be a host of expert speakers presenting on topics ranging from sporadic E, and how to use AI to write amateur radio applications, to […]

Jamboree on the Air (JOTA) is taking place 18 to 20 October 2024. The event promotes friendship and global citizenship, and is a brilliant celebration of amateur radio among the groups within the Scout Association. Some groups have already shared details of activities that will be taking place over the weekend, and the RSGB plans […]