Please find below a video by Fraser, @MM0EFI giving a step by step on how to purchase and code your LoRa tracker:
Thanks Fraser 
1 Like
Amateur high-altitude balloons are at least partly responsible for getting me into amateur radio. When I was active most of the balloon payloads were using 10mw ISM transmitters to send RTTY on 70cms, and I was usually using an 817 and a tri-band colinear, one of those 6 metres, 2 metres and 70 cms beasts that were common at the time. The greatest distance at which I successfully decoded a packet from one was something over 500kms, but the balloon would have been somewhere close to 40kms up at that point.
However, for this game, it’s the balloon doing the listening, and rather than just having to watch one signal, its frequency will be full of LoRa signals from all the hopeful folk trying to get it to hear them, so quite a bit is going to depend on just how its LoRa receiver handles multiple signals on one frequency…
Incidentally, if you want to experiment with receiving signals from a high-altitude balloon then I noticed on the UKHAS mailing list that Bolton Wireless Club are planning a launch probably early next week (but the launch window starts this Friday) which will have a CW beacon on 2 metres, and both LoRa and old-style RTTY on 70cms, all working at about the 10mW level.
3 Likes
Hi all, I am new to this forum and decided to join as I came across this post regarding the upcoming Lora Balloon Challenge. I have recently come back to the hobby of Amateur Radio after having a few years away due to family / work etc. Since my return I have been mainly using APRS, mainly hitting the repeater on the ISS with my Yaesu FT-5D.
A friend of mine who is also into the hobby tagged me on the RSGB Facebook page for the Lora Balloon and immediately I was interested as I had never heard of this before.
I ordered the board, set it up and now my tracker is ready to go. The PDF instructions were very well documented and made it easy to complete the steps and follow along. I watched Fraser’s video which was very informative and was a great addition in helping me set up my tracker.
So from me, thanks to both user’s for providing these format’s it is much appreciated.
I have attached some photo’s. I 3D printed the case from one of the examples that were in the PDF instructions and attached a right angle connector with an additional BNC connector for my antenna which is a Watson WHX-7000. Hopefully this will be enough to send and receive packets to the repeater 
.
I doubt I am going to win the competition but at this point I am just glad that I am along for the ride 
.
12 Likes
Well done and welcome onboard!
2 Likes
Note that this LoRa was UKHAS format (not APRS), which interleaves telemetry and slow-scan pictures on 434MHz. More info here: Bolton Wireless Club - 2m beacon
1 Like
It’s been a while since I did any HAB tracking. The LoRa data needs a LoRa receiver, but the RTTY can be received using something like an 817, and is usually fairly easy to decode, unless the frequency and shift are being variable (as was quite common in the early days because temperature variations messed with the oscillators). Getting the fixes you receive into the HAB tracking websites, however, always involved a bit of hackery one way or another. Back in the day it was a modified version of fldigi that did the trick. These days there’s some UKHAS code to do the job.
It will be very interesting to see who can actually open the balloon digi and from what distance/balloon altitude.
1 Like
Assuming a good number of folk are running appropriately tuned trackers, that’s going to depend quite a bit on how the LoRa receiver on the HAB copes with receiving several signals at once. If the HAB gets to 40km then trackers 500km away could be in with a chance, but I suspect the closer (well, stronger) signals will get through a lot easier. I’m guessing a decent 70cms yagi (presumably vertically polarised) and steered to point at the balloon will increase your chances, as will actually getting packets sent suitably frequently.
…and some of it’s going to be a matter of luck; where the HAB goes in relation to you…
1 Like
Rick is correct that as the balloon goes higher, the area covered increases. For me as I said at 350km nominal distance the balloon rises above my horizon when it is 10700m ASL. At that point everyone in an area of 385000 km^2 can see the balloon. The UK area is 244376 km^2. That’s why I said I’d need a bit of QRO to guarantee I was loud enough to get over the nearer stations.
I did order a unit from China direct but despite ordering a 433MHz unit, they sent an 868MHz unit, now returned and refunded. I did that to leave the shop stock unaffected for people who didn’t want to buy from China directly. So I no longer have a dog in the race but a good mate in my local club is going to have a go. He’s been looking for a moderate antenna to improve his chances. I have a 440MHz PA module from a PMR radio which can give 15W for 100mW drive. Maybe something can be concocted in time to improve the chances of him being heard. If it was a “fair” system where everyone got a chance to send one packet with no other user’s QRM then the theory says it should be viable from here with a dipole and 100mW. But it will be a free for all so a bit of power is needed.
This event it has stirred up interest in playing with bits of technology that many people would never have bothered with otherwise and that’s a good thing.
5 Likes
Just over a week to go, is everyone ready??
1 Like
My board is still en route from China, and the delivery date is forecast to be the 19th - 24th, so I might be beaten this time round. I will be getting the software up and running on my laptop, ready just in case it arrives before next Saturday.
Hopefully there will be something like this again in the future - I think it is a great initiative, and thanks to Ben, Fraser and everyone else involved with setting it up and documenting it. I had my final week of paid work last week - I will be more proactive in the future and not procrastinate before ordering the bits!
Good luck everyone!
3 Likes
You won’t need to wait for another flight, Paul. With only a few changes in the config (particularly the Tx & Rx frequencies) you can use your new tracker on the terrestrial APRS network, which has seen an extraordinary growth in iGate coverage over the last two years:
When I started using my tracker from the local moors, it was only picked up by three iGates (in Shropshire and the Welsh borders), but now there are more than twenty in range and it’s even received when I turn it on in my back garden!
3 Likes
Thanks Ross - I had figured this, but I was hoping to get involved with the challenge first! I actually ordered two boards, so I can put them to good use. Looking at your heat map, it looks like I will be well served around here in Mold, North Wales.
I had some good news this morning - my package has cleared customs and is waiting for the local courier to collect it for delivery to me, so I might just be in luck! I had better get cracking with the software installation, and building the yagi…
Is it 200mW erp for this one. Maybe wron?
1 Like
According to section 3 of the published rules (at the top of page 5):
The output power level must be set to less than or equal to +23dBm (200mW) EIRP.
Don’t forget to factor in your feeder loss as well as antenna gain.
4 Likes
I’m as ready as I’ll ever be. 7 elements fits on a 1m pole. Flat SWR across the band.
I think I’ll head up The Buck of Cabrach GM/ES-039 for the event.
7 Likes
I’ve just received this prediction for the trajectory of Saturday’s flight (thanks Nick):
This is based on the assumed ascent rate, burst altitude and the latest model for the air-currents at different altitudes.
Incidentally, a Polish APRS balloon flew across the country earlier today and was picked up by a number of 2m iGates:
But that was a floating “pico-balloon”, at around 14km altitude.
4 Likes
Looks like the lucky places to be are probably Cornwall, Kent and north of the Border, if you can get your signal heard. 
1 Like
If anyone needs assistance on tracking the balloon on the day (tomorrow), as well as your signal if you hit the digipeater, below is a link with instructions, kindly created by our very own @G1JKS Dave Pegler 
good luck everyone!
73, Ben
GW4BML
3 Likes