hpr-knowledge-base/hpr_transcripts/hpr4213.txt

Episode: 4213
Title: HPR4213: Making Waves Day 1
Source: https://hub.hackerpublicradio.org/ccdn.php?filename=/eps/hpr4213/hpr4213.mp3
Transcribed: 2025-10-25 21:30:23

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This is Hacker Public Radio Episode 4213 for Wednesday, the 25th of September 2024.
Today's show is entitled Making Waves Day 1.
It is part of the series' interviews.
It is hosted by Ken Fallon and is about 39 minutes long.
It carries a clean flag.
The summary is The Hallway Track from Spectrum Day 1.
Hi everybody.
My name is Ken Fallon and you're listening to another episode of Hacker Public Radio.
Today from the hallways of Spectrum 24, the conference for the creative use of the radio
spectrum in open systems with the title Making Waves.
That was held last weekend, which was the 14th and 15th of September in a small town just
outside of Paris.
If you've been to Foster M and have been at the Amtra Radio area or the radio area itself,
you'll get a feel for what they were trying to achieve here.
There were a lot of really cool projects, so I will introduce some of those projects
to you now in short little snippet interviews.
The presentations that people gave will be available on the conference website.
So without further ado, sit back, relax and enjoy the presentation.
We're at Spectrum 24, I'm talking to.
Sylvan, I'm a Fox 4 Golf Kilohadio, the president of the IARU, Region 1.
Excellent.
Why are you here today?
Because this is an event organized by some Amtra Radio guys, but it's not only dedicated
to Amtra Radio, it's dedicated to innovation and things that could look strange but could
be of interest for the Amtra community, so that sounds interesting.
Sounds like hacking to me.
Well, I didn't want to use that word, you did.
And what is your background in Amtra Radio?
Oh, my background is more on SDR, in fact, I'm a software developer.
And I decided to have my license because I needed to test my code, so I wanted to do this
with real service, just to have the permits.
So we're here because you've been able to get the venue, it's been a great venue.
How do you feel like it's been going so far?
Well, that's a very good question to be honest.
We had no clue how many people would be coming, and we're pleased that guys are coming
from quite far away are here, in fact.
The quality of the people here is amazing, the conversations that are going on is just
mind-blowing.
Yeah, that's true, that's exactly why we wanted to do this, just basically to make people
don't know each other, start discussions and exchanging ideas, that was just the main
goal, in fact.
And you mentioned it in your presentation, the field is very much like the Amtra Radio
track on Fostem, but even more Amtra Radio, even more, or AFI.
Yeah, exactly.
The idea was to dedicate two days to people coming from different communities, and having
just one coming background, which is Waves, that's why this making Waves name came.
That was, the intention is make waves, use the spectrum for things that are just fun.
Okay, perfect.
I have one serious question, I really hope this is going to be happening again.
Is this one other thing, or are we planning on reinventing the wheel, or is it too early?
No, it's not.
No, the intention is a start.
We said yes, if we have a few guys who made the effort to come, then it's worth doing
it again.
Thanks to the others, we have already received the proposal to host this next time.
So...
Excellent.
Okay, I'll let you go, because I know you're trying to gather people around here, and
people are just ambling in still, so thank you very much for your time and enjoy the
rest of the event.
Thank you very much.
See you soon.
Hi, we've had the presentation about F4 Kilo Lima Oscar, and I'm talking to one
of the project members.
Your name is?
François Xager Hugo, and five FXH.
And can you tell the listeners what F4 Kilo is?
So, F4 Kilo is a big dish of 10 meters to do radio-astromanical observations.
It's quite old dish, because it has been bought by the Cité des Siens et l'Angusterie
in Paris in the year, something like 86, 1986, and it has been unused since, during
30 years, and recently we had renovated it, and it's now fully functional.
Okay, super.
It seems like a transparent wire dish, how wide is it?
Sorry.
Physically, how big is it?
It's 10 meters diameter.
So this is a heavy, big beast of a thing.
Big baby, yes.
And it's got motors and controls and all sorts of things.
We have fully controlled two axes, right ascension and declination, we can fix, for
example, any, almost any, because we are in the north hemisphere, but a lot of astronomical
objects during eight hours tracking it.
Okay, that is, and for those of you listening along, we'll have links in the show notes,
but every classic science fiction movie where there's an observer on the ground and
the dish pans in slow motion or in spin-off motion, that's what we're looking at here.
So what do you use, how did you end up with this dish?
Are you know, I bought it on Craigslist or on Facebook Marketplace or something?
It's special, it's with Remy and five CNB, which brought me to his suitcase and it tells
me, it's a good project, come with me and we did a lot of very, very interesting things
there.
So how did you end up getting in possession of the thing?
What was the use for first?
It's special, it's, well, it was Bernard F6BVP, we, at some point, he came here, he came
there and he saw that the antenna was unused and he went to the citadacials and asked
them if we could do something there and it was started there and after we have renovated
it and at some point we lost one motor, which was fixed by FabLab the non-ther and after
and no, we are fully functional to axis and we can fix any, any, any astronomical object and
listen to the, you know, to the music of the H1 atom.
Wow, cool, and so in practice, would I be able to use it?
You can, anybody can be a user, we have some, some, some fronted available by internet and
abnet and so almost anybody can be a user, you just have to, to, to, to be a, they run to
the association of course and it's okay for everybody to come.
And do you need to be a licensed amateur?
No, no, no, no, because it's only, well, this part is only listening.
We have some part, maybe you have seen the, so in the presentation, so you have some
earth moon, earth communication, but well, the part I am doing is essentially radio astronomy.
Shall we get your cold pilot in?
Yeah, of course.
Hi, sorry, I'm springing this on you, you get the presentation on, on the satellite.
So what's your name, introduce yourself?
Oh, yeah, I'm Jules, I got five call signs, but you can just call me IEY, I'll do it.
Okay.
F4, IEY, and well, yeah, I'm, I'm indeed like a, a member of F4KLO, like I've been the
member for no long time, actually, I just discovered the club, like, something like three
months ago, something like that, I was, because I'm a V, I'm a VE and we organize sessions
with Remy and the radio club and it was actually different, very first time I like got to
see the whole set of things and I saw like the whole potential and stuff and I was like,
okay, well, no, let's just fire it up and try some of the things and as I'm a CW operator
mainly, that's my main thing.
So I, I tried to at least put like a decent set up for it.
So that you're from the VE is Canada and CW is more skilled, I guess.
Yeah, CW is in the Morse code and V is not Canada, V is for volunteer examiner and
yeah, it's, it's like an organization to how people passing the American license and
you can basically do that in every country, which you just need like to belong to an
organization and then you just like schedule sessions and people come on and you know,
pass the exam.
Can you do the exam online?
Maybe I'm detouring into another topic, does it interest me?
Yeah, just real quick, you technically can, we just as an organization do not offer
that, there's like plenty of other that does.
But for now, we just like doing the, you know, in person exams.
So the presentation you gave yesterday was there anything that you want to do, you mentioned
here?
Well, basically, you have a lot of things that I already presented that maybe a little
bit more detail about the, I'm sorry, the EME set up because there's like another,
like a plane of other things, I'm, I'm going to see that you guys in Morse code kind of
course.
So yeah, I'm mainly using, let's say a key, like the micro key or two in the rig, but
there's like other people using the Q65 and you know, digital mode and they're all like
all PC plugged in.
They use the SDR or speed to do to like listen to all the signals and compensate a lot of
factors like Doppler and goes and stuff and it's actually very interesting, but it doesn't
like, it doesn't bring you to same feeling as doing a CW contact over moon because over
the moon, right?
Okay.
I was going to try and drop that in there.
Yeah, yeah, yeah, yeah, like CW contact over the moon, you can hear yourself back, which
is very cool.
Like the first time due to the speed of light, the amount of time it takes.
Like the moon is like three hundred thousand kilometers away.
So yeah, the around trip takes two seconds and yeah, Q65 is not the same thing because
you don't hear anything.
Just look at the screen and you know, you do contacts like you click in.
It's not my, not my type really.
Fantastic.
Listen, links to the presentation will be in the show notes for this episode was the
round thing else that you wanted to mention?
Apart from the fact that we are focused on, on, you know, amateur radio and space, I'll
just, for all the radio amateurs here, more than the HF community, this is a great opportunity
for you to discover, you know, amateur in space and especially EME, which is a very
specific part, but I'm sure you're going to like it.
Cool stuff.
Thank you very much for taking the time.
I'm talking to Antoni and you have just given a presentation, what was your presentation
about?
I am a teacher at Le Mans, Lissé Touchard Washington, I learn electronics and IT computing and
I build, I'm a radio at school, to interest student, to radio communication and learn
to build antennae, how to make a QSO and simply in QSO and build some project with, for
example, a Raspberry Pi and Arduino to make a receiver, a transmitter and to prepare
them to get the license.
So it's a voluntary course, you're a teacher I presume and presumably you have, you teach
computers or something.
Yes, yes, I teach electronics and computer technology.
But there is one hour per week to...
The extra collicular stuff, yes.
Okay, and it's free for all of students, but the time is not included in their timetable.
So it's difficult for me to get in the radio room and the interest to come back the next
week.
Exactly, so you don't definitely don't have enough time to do a course, but you're planting
the seeds to get them interested in technology.
You had some Raspberry Pi's there, I saw some balloons, I saw you had a 2 meter antenna
tell us a little bit about the cell-up and some of the technologies you're using.
For the weather balloon, it's very easy because we can include the project of the weather
balloon in the air exam at the end of the year.
So the project balloons are included in their time, there is about 6 hour per week to
study and to prepare the launch and the student will the cards and make all the programming
with ESP32, Raspberry Pi or Arduino.
So there's more time for that project than there would be.
Yes, because we include the project into ESP32.
And you've got a server rack there, all you seem to be able to use a lot of information
that was available on the web.
Yes, I publish a lot of articles and the articles you find in England, USA, France,
Spain, Europe, the trend and Belgium.
I wrote a lot of tutorials to get more easy, easy to build something for a person who
don't know the radio techniques.
It's a fantastic presentation, hopefully there will be a link to it in the show notes
for this episode.
Is there anything else you wanted to mention?
No, I think there is another project.
I am also a fan of retro computing and I build my own ORIK1 and ORIK Atmos.
This is an old computer, but I am a fan of that.
I look forward to getting you to do an interview or an episode on Hacker Public Radio about
that in the future.
Thank you very much for your time and enjoy the rest of the show.
Can you introduce yourself?
Yes, my name is Mike Swingey, Oscar III, Mike Zulu-Charlie, and I am the president of
the Institute of Citizen Science for Space and Wireless Communication.
We are presenting Meshcom, which is our Mesh network using Laura Modulation on the
70cm band.
So what's the Laura device just in case?
A lot of our guys are not amateur radio operators, yes.
So can you give us a brief rundown of what a Laura module is?
And do you actually need a license to run Laura?
Actually these Laura modules, there is a couple of them available on the market.
It's from Lily Goh and from Rack and Haltek and just the name of you.
So it's T-Lora and T-Pee and some other models.
So it's a cheap combination of a Laura module, so the transmitter and receiver itself,
and an ESP32 CPU.
So you have some peripherals, you can add a little battery.
And by doing so, you have a tiny little module which actually will enable you to transmit
short messages, but also telemetry data from sensors and others.
But also your GPS position obviously.
And by transmitting them via a spread spectrum, Laura Modulation, you can even achieve with
low power a long range.
So we are talking 20 kilometers or even more.
So they are very popular in the IoT field and in farming and they are all over the shop.
And when something becomes popular, it becomes cheap.
And therefore you step in with your project.
Exactly, so the availability of these cheap modules, they actually encouraged us to look
into it more deeply and think what we actually could do with them in order to experiment
in amateur radio, but also in hecka space or whatever.
And the interesting thing about this is actually that it is a mesh network.
So it forms a mesh network, you don't need any centralized server.
Every and each node that you switch on is actually automatically a repeater and will repeat
your message and will so increase the range and the coverage area.
So if you can get 5 kilometers between two, you can get 10 kilometers, 20 kilometers,
ideal for disaster situation, I reckon.
Exactly, we are using it as a completely independent network for disaster relief situations,
floodings, like unfortunately we have some flooding in Austria and some parts of Europe right
now.
So that's whenever you are losing the telephone connection and the internet, then that's
a perfect fallback thing.
Although we also have centralized components, you don't need to have them, but we connect
using HamNet and also the internet.
So some broadband, we connect the lower clouds, the local and regional lower clouds, we connect
them to a centralized server.
And so you can even interconnect the different regional clouds and in order not to spam all
the different clouds with different languages and different messages, which you probably
don't want to see.
You can even filter them by using the talk group system that we all know from the DMR system.
So for example the talk group 232 would filter all the Austrian messages.
And even though I am here in Paris or around Paris in France, I can actually listen to my
friends messages from Austria.
Just by using this talk group as a filter in the Meshcom network.
So just for the guys who are not Ham's, what can they expect is that we are not talking
voice communication here is mostly text.
Yes, even though you can use voice to text input facilities, what you transmit and what
we transmit is actually text and data.
So it's not broadband, it is a narrow band communication.
So we are talking about speed levels of 1200 bits per second.
But on the other hand it is very, very reliable, so very low power, so battery will last a
lot a long time.
And on the other hand you can send these typical chat messages that you would send via WhatsApp
or telegram or signal or whatever, which is something that everybody is used to do and
a lot of also family communication these days using it.
So why not using it in amateur radio or in disaster relief operation.
And the devices will go through your table here, but the devices are small enough to put
in into a lunch box and put on the top of a hill somewhere tall building if necessary.
I see here that you got like an ESP RM 18650 battery and there is a ESP 32 with a device
on top of it.
Do you know what I'll do?
I'll take some photos and put them into the show notes.
Yeah, I can give you some more description on that.
So actually there is a little display, but it's not meant to interact with the user via
this little display.
It is meant to connect your smartphone to it.
So via Bluetooth on the smartphone app you actually use the functionality and the little
module is only the transmitter for sending and receiving the Laura's signals.
So you could install the app on say okay there is a point you need to be an amateur radio
licensee in order to operate the network.
This project actually addresses amateur radio, but the principle can be used by everybody.
It's just a legal question of access to the spectrum, but it's free and open source.
You can get it on GitHub and you can also use it on 868 megahertz, for example, which
is a free frequency.
So it's not a particular closed system for radio emitters, but it is focused on radio emitters.
So what is the focus?
The focus is experimenting.
So we want to see which signal has propagated, what way using which repeaters, which mountain,
and how to improve it and things like that.
So that is in our focus and that was leading to this development.
And also let me mention that we have connected it, interconnected it to other radio amateur
radio systems like APRS, VIN link, like DMR texting, sending SDS, also via tetra radios
and things like that.
Or even pages.
You can use these POXARC pages.
So the strengths of this system lies also in the interconnection with other already existing
amateur radio systems, which allows us to use all the tools that we have already built
for them.
So for example, for APRS, there is APRS.fi, a very well-known website where you can have a
look at the GPS positions, but also you see the telemetry already with very nice graphs
and everything, history is there and a lot of things we don't need to recreate this again
for Meshcom.
We can use the existing tools and systems.
That's one of the benefits of this Meshcom 4.0 we call it, system, and yeah, it has
a lot of fun and it's open, so free to experiment.
It also got not just a dashboard where you can, you know, these dashboards from the DMR world
and the D star and all these digital voices stuff, you also got a dashboard for Meshcom
and your lower messages and that's something that fits very well into the world of amateur
radio.
How would this compare to something like Meshtastic?
Yeah, the comparison is that the idea is very similar.
Again, what we have done is we also have some centralized servers where we can interconnect
the clouds, so that is something we have learned also from digital voice but also from
HamNet, so we have our own broadband network in Europe, so why not use it for this and
so you can actually interconnect local nodes and local Mesh networks to other parts of
the world by simply using the Internet or the HamNet.
So this is one of the significant differences.
The other one is this approach of unified communication, so for example, you got interlinks
to all the other existing amateur radio communication means like APRS and windlink and as I mentioned.
Yeah, that makes it certainly very flexible and we will see what's up to come.
Next.
Can you walk us through some of the devices that you have, we've already looked at the
Meshcom device with the battery.
Yeah, there is basically two different devices.
One is these devices which are from Lilligo like T-beam and T-Lora, so the only difference
is the size of the battery probably and the T-beam also includes some GPS on board, so that
makes it a little bit more bulky, so to say, but still a very nice size.
The other one is very small and uses the GPS information from your phone because it's connected
to your phone anyway, so why not use it?
And then there is a lot of health tech devices which are also very flexible and cheap.
And then for the gateway, I mentioned that you can connect your local node and your local
cloud to a server, we do that by using gateways and then we use rack modules from the company
rack.
It's up to you to choose and there is plenty of things to choose.
By the way, to set it up is very easy, connect to the website of icssw.org, use the web
flesher and connect to the correct comport and up you go, just enter your call sign or
name and the messages are ready to be sent.
How much is one of these devices just?
I don't know, it's probably between, I don't know, 40 euro and 50 euro or something like
that.
So it depends a little bit, we buy them in on the market so wherever you get it is free
to use.
And also you can include some sensors, so there are these typical sensors like the PPM,
280 or whatever, so it will include temperature and humidity and pressure and I don't know
what.
And that could be easily be fit to these modules and on the website you will find instructions
about the wiring and things like that.
Fantastic, thanks very much.
Was there anything else that you wanted to cover into that we skipped over?
Just let me mention that there is not just a connection via Bluetooth with the app, but
you can also make these modules to create a Wi-Fi access point, so then there is a web
server and like you are used to set up your router or any other device, just connect to
this web server to the web page with your browser and you can do all the same things, so set
it up, configure and also send and to receive messages.
Perfect.
Thank you very much for your time, it was an excellent presentation, links for this will
be in the show notes for this episode, so hopefully we get to talk to you next year.
So welcome, thank you very much for the opportunity, no problem.
And can again live here doing the whole way track at Spectrum 24 and move it over to our
neighbors here at the HPR booth and we are with the sat down guys, so can you introduce
yourself first?
My name is Jakobo, I am from Italy, I am a ham guy that develops the scientific side of
the sat down software and with me we have also three other developers and one of them
is right next to me and hello, my name is Bigniew Stanga, I am from Poland, I am developing
sat down together with Alan and Jakobo and I work mainly on the calibration so the step
between decoding the data and making it into something useful for science.
Super, so let's take one step back, what is sat down?
Who wants to take that?
I will take it.
So sat down is a very flexible software that runs on any computer and on some smartphones
and tablets as well and it is used to decode live satellite data, recorded satellite data
that is sent from basically over 90 satellite systems in orbit around Earth and it includes
like meteorology data, images of the sun, images of the Earth, far away space probes and
everything in between.
But surely all that stuff is encrypted and legal to download.
Fortunately it is not, most of the stuff is completely unencrypted and several of the
bands are either in the amateur band or in other bands that are meant for direct reception
such as the popular APT and LRPT weather satellites and the geostation is satellites in orbit
around many parts of the world so it is completely free to use.
Do you need to be an amateur radio licensee in order to receive this stuff?
Absolutely not because it is actually just reception, you don't transmit anything but
it could be like it was for us, a pathway into radio amateur and into getting an actual
license once you get the hangout of radio because radio is not just talking, it is many
more and many much more than that.
I must admit that my first job in the Netherlands was working on satellite internet so this
is right up my street, I am trying to be as introductory as possible here for people
so can you tell me a little bit, you do the software, what else do I need in order to get
into the hobby?
Absolute cheapest entry level, I want to get an image of something, what would I need
to do?
Well basically all you need is a small antenna and an SDR and SDRs are really cheap nowadays
you can get an RTL SDR stick for like $20 I think and just a piece of cable and then antenna
you can literally make it out of wire, just a V-diple with two pieces of wire and that
is pretty much everything you need, other than a computer of course, a smartphone and with
that you can get pretty okay images, they of course won't be there, great quality,
a sat-dump can achieve but they are definitely useful for meteorology and they also just
look cool.
It is a good start, but then you start getting interested, what else do we have here at
the table?
Well here we have some feeds for higher bands so basically the antennas are more complex,
you are required to use a dish with a special feed for the higher frequencies that is like
over gigahertz and a couple of gigahertz, so you definitely need an antenna, you also
start to need an amplifier and a filter, you can get that on Amazon easily, it's pretty
available and so let's talk about the dish first, could you use a normal like sat-dump
satellite TV dish that you can pick up relatively cheap or free?
Absolutely, anything over 70 or 80 centimeters will be great and you can find the old dish
your neighbor has.
So when you say 70 meters you take out a measuring tape and if it's 70 meters, the bigger
the better with satellite dishes but yes?
Pretty much yes.
Okay.
So then you have the satellite dish, you got one from your neighbors, then what do you
need next?
So you need to make actually a feed which is the part that converts the actual radio waves
into electricity that can be sent to the computer and that can be made really easily if you
have a 3D printer, but even if you don't have a 3D printer you can just build it yourself,
I mean it feels out of wood and Lego and you just need a wire which is called in an appropriate
way and can find the dimensions on the internet very easily.
So is this a feed here that I'm looking at?
I'm describing what would essentially be a child's art project, no offense, but it's
a piece of aluminium, very precision cost with the scissors, by the looks of no offense.
It does look like something that I could put together, probably not as well.
And coming out of that is a, what do we call that type of connector?
To make a connector you can get them for basically peanuts on Amazon.
Yep, and they're all not really expressing everything.
And then out of that is what essentially looks like a piece of household electrical wire
that you might have in the AC adapter for your laptop and that's coiled around very artistically
around the 3D printed thing, it's about the size of your middle finger I guess and yeah
it's just a coil wire that if you could possibly even coil it around a toilet roll
core or something like that.
And we actually did it already, so.
Okay, so you've got a toilet roll core, you've got a piece of aluminium foil as ground plane
and you wrap that around and then you've got an antenna.
I'm not going to go into polarization at this point, but so we have those two things we have
our dish, we have our antenna, then what?
Well, you just need the radio, which can be bought on Amazon, which is as we already said an RTLSDR,
which is about 30 to 40 euros on Amazon, but you can get it cheaper from China.
And you just need the computer and the sadam software, which can be of course downloaded for free.
And those sticks were originally for satellite television, but.
Yes, they were for terrestrial television and satellite TV, but they can be basically reprogrammed
very easily with a few clicks or even no clicks if you use macOS or Linux and just work as a satellite
reception tool. Okay, so that's cool. Now, what else do you have for the real professionals here?
For the real professionals, you can switch to much higher resolution satellites,
satellites with a resolution of 60 meters per pixel, so you can see houses and
ships in the sea and whatnot. And then you can also get the images of the sun,
you can get space probes, you can get the images of the entire Earth disk, so you can see basically
the entire Earth illuminated as if you were taking a picture from space. And also you can get radar
systems and anything in between really. We do support new satellites as they come online and as
they are launched. That is absolutely amazing. And the presentation was fantastic. From every level,
no matter what your interest in science and technology, there was something in that presentation
for you, pity that Alan couldn't be here, but hopefully we'll catch up with him at the next
spectrum 24. So tell me what we have, what are you demoing here on the table?
We are demoing several new technologies. One of them is an expand, so very high resolution,
very high data rate receptions set up that can be used to receive the very juicy high-detail
satellites like the ones in Google Earth. And we are actually working to bring that to the
masses with the introduction of cheaper components that you can buy in a few months probably.
What's a copyright on those then? They are basically free to use because they are taken by an
automated satellite. They are meant to be received by actual end users, even though nobody knows
about that. It's actually called direct broadcast for a reason in the spectrum.
So, because they haven't been manipulated, it's not possible to copyright them.
Absolutely. Absolutely.
Basically, they are copyrighted by the satellite operators, but you can use them. They can't
prevent you from using them and it's completely legal, but you have to acknowledge that they come
from this specific mission. Okay, I'll need to get my head around that particular one, but that's
quite interesting. Yes, yes. My presentation yesterday was more or less on copyright.
We're almost finished. We're being bugged to go back in, but it's a good time to wrap this up
because otherwise I would go on for ages on this topic. Listen guys, anything else you want to
point out here or anything else that I missed? Just go on our website, satnam.org and you can find
any information you need, including easy to understand guides to get into the Hoppy.
Yes? Absolutely. Okay, okay. Thank you very much.
Gentlemen, and I'll talk to you later. So that was most of the presentations from day one of
the conference, and tomorrow we will be posting day two coverage. So tune in then for another exciting
episode of Hacker Public Radio.
I just can, with our continuing coverage of the hallway track at Spectrum 24. Sit back and enjoy.
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