Continuing the discussion from LoRa APRS Tracker (Part 10) - #100 by G4TGJ.
Previous discussions:
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I’ve been away for a few weeks and only found time to try the capacitor mod for the Heltec tracker today. I had a small, 400uF 16V electrolytic to hand so used that on a short flying lead. I just managed to fit it into the case, beneath the SMA socket for the antenna. I’m pleased to report that it appears to have fixed the boot-loop issue…for now at least 
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The problem I’ve found is that when the battery gets low the tracker tries to transmit a spot, the voltage sags and it reboots. When it comes back up it tries to transmit again and immediately reboots. It keeps doing this until the battery is properly flat. The worst thing is I think it actually does transmit and so spams the APRS server.
The fix may be to set the battery low setting so it shuts down before this happens.
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I think this added capacitor might have really fixed mine It ran, on a fully charged battery, for just over ten hours. The cell dropped to 2.95V before the tracker died. It didn’t exhibit any boot loop issues before it died, it just stopped working. I’ve fully charged it again today and it’s working again just fine.
I think the cap I added had a greater value that some folks suggested so perhaps that’s sufficient to smooth out the voltage snags on transmit?
Cheers,
Denis
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As of yesterday the SOTA shop has started selling the complete LoRa APRS tracker.
SOTA APRS tracker, aprswireless at SOTA Awards
SOTA APRS Tracker with various options
You can either configure it yourself (i.e. add your callsign) or ask them to do it for you.
Another option: they sell just the case, 2000mAH battery, switch, SMA to IPEX connector and JST cables and you buy the Heltec tracker PCB separately (e.g. from Aliexpress.com) - as I did - download the firmware from the internet, and fit the PCB, battery, etc into the case.
And finally, they sell an accessories kit: a EU433 flexible antenna (3dBi), a separate USB C charging / docking station (and USB cable), belt clip and wrist band.
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I know there has been a lift on 2m for the past few days….
But …… @M0MZB well done.
Your DigiGate in the lakes got me on Mynydd Troed GW/SW-009 at 173 miles yesterday !
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Please excuse my belated comments - I’m still slowly working my way through this 11-volume boxset topic after getting involved in the Cumbria LoRa APRS project only a few weeks ago …
Continuing the discussion from LoRa APRS Tracker (Part 6):
In case, this wasn’t confirmed in the next 5 volumes …
[Wikipedia: Chirp spread spectrum] Additionally, chirp spread spectrum is resistant to the Doppler Effect, which is typical in mobile radio applications
Quote: CSS has been considered as possible candidate for low-power LEO satellite communications due to its resistance to Doppler effect.
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My contribution to that is still brewing! Im hoping the Walney Island Igate will be up and running in March… I have my parents permission now to mount a small antenna on thier shed, so its Igate a gogo!
Alan
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I’m sure that would be most welcome.
We are starting to explore the gaps in coverage especially below the main summits. Since I got my iGate and tracker very recently I’ve been monitoring (not always live) the tracker trails of anyone in G/LD and G/NP. I’m very impressed at how the network is becoming more resilient as additional iGates and hilltop digipeaters have been deployed. This is evident when ‘hovering’ over successive tracker ‘pings’ on the aprs.fi map and noting how the ‘winning’ route often changes quickly from one iGate to another or digipeater / iGate.
We are stuck with the locations of our home-based iGates [unless you can persuade your spouse on a move to a ruined hillside farm] but the strategic deployment of the two unobtrusive high-elevation digipeaters (one in G/LD and one in G/NP) adds greatly to the network.
While it’s good to get dx coverage driving on the main roads [I got 100% driving from my QTH to Southport last week. And I’ll be driving to Annandale M74 services today so that will be interesting], yesterday I got 0% coverage [aye, nowt !] doing a (very popular) riverside walk in the Little Langdales surrounded by lovely looking but RF-unfriendly hills.
It seems better where the topology is more gently rolling e.g. 100% coverage for G4TGJ-7 up to Calf Top (G/NP-022) yesterday. The big challenge are those deep valleys so I would welcome more iGates but especially more well-placed digipeaters and where desirable with directional antennas and/or a bit more power (if that’s allowed).
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I also have a spot for one just north of kendal aswell if one of the local lot wishes to take advantage, i can have a word! Pal of mine owns a farm up there, in the grayrigg area. im sure he would be happy to host either a digi or a gate.
Alan
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My QTH has been under a power cut since about 0930hrs on Friday, with occasional periods when power has been restored
M0MZB-10 has proved useful in being able to remotely determine if i have power to my QRH…using the online APRS maps, i can tell whether i have power by whether M0MZB-10 is up.
I have also been without landline internet, even during the brief periods when power has veen available, and M0MZB-10 has been igated by the igates in South Cumbria.
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That could well fill some of the radio shadows in the Shap Fells, Borrowdale and the Howgill Fells not covered by existing iGates & digipeaters. I found the deep-valley section of the M6 east of Kendal up to Tebay a black hole for LoRa APRS as it is for DAB and FM radio.
The truth is we won’t know what the coverage is like in detail until we get folk walking up dales to summits with their trackers. Coverage models can only give a coarse estimation. Activators, please take your tracker or borrow one next time you activate in G/LD or G/NP.
We definitely have poorer coverage in the north of the county. On my trip to Scotland and back today there’s poor coverage north and south of Carlisle from the M6 anyway though I got one lonely final ping near Gretna.
Do we know any RA living in that area who might be persuaded to host an iGate or digipeater?
New to me: I got my wife to read off the tracker’s ‘Last Rx’ callsigns as I was driving south from Carlisle this afternoon. Turning off the M6 near home, she said it was now SP0LND-3. I said that’s a Polish callsign and impossible so she sent her Doubting Thomas husband this photo.
On qrz.com SP0LND-11 is Damian Osiecki’s balloon so I’m guessing SP0LND-3 is the same. Nick @G0HIK said they are high altitude and folk launch them to see how many times they go around the world. He thinks one recent went 3 1/2 times around before it failed. Apparently, their trackers change their 70cm frequency every 30mins to transmit on all the worlds different standards. Apparently, it was over southern Ireland at the time.
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Actually they cycle around the LoRa frequencies every couple of minutes, and today’s flight was sending FM-AFSK on 144.8 too (albeit using a 70cm antenna?)
Here’s more info on Damian’s balloons, and a list of all his flights.
We also had DJ2DS-11 come across on Friday (only on 433.775) and then SP0LND-1 yesterday, but they both passed overnight, so weren’t transmitting.
Today’s flight came across EI and GD, but it was struggling to get enough power for a satellite fix, so it was sending null positions a lot of the time:
im not going to post his location on here, but i will send you a PM!
Alan
Coverage in Cumbria is certainly a lot better than even a month ago… good stuff. Carlisle is the stand-out problem area. G3WGV-11 is screened by the Pennine range with no coverage on the M6 from about Southwaite services until the Cumberland Gap/Gretna.G3WGV-10 does fill in a few gaps but there’s still a lot of not-spots.
There are loads of amateurs around the Carlisle area, so hopefully some nodes will turn up soon. The south of the county is pretty well covered now.
What we really need, as Andy says, is more trackers. It is rare to see any active trackers other than those that belong to node sysops.
It looks like my home iGate first heard from the balloon when it was over 6000km away. Apparently, other iGates & digipeaters in the area got similar results - probably the same anywhere in the balloon’s path…
It helps having one’s antenna at 37988 ft ASL.
Come the warmer weather when the sun is higher in the sky, I’ll reinstate M1BUU-10. At the moment my shack battery is struggling to even power the shack lights. My 6 year old lead acid leisure battery is tired now.
Someone mentioned messaging earlier, there is a keyboard on the LILYGO® T Deck but I have yet to hear anybody using one on 439MHz, you also need to source an enclosure and a decent antenna.
This is very true, I was impressed with the APRS coverage yesterday walking up GW/NW-042 yesterday. My tracker even managed to ping M0MZB-15 in the Lakes 10 times, that’s a 100 mile trip,
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In case anyone doesn’t know of this website, the multiview has some interesting information
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