Hello! I am pretty new with Flextrak and weatherballons and wanted to ask some questions!

[Lucas Castillo]

Basically, when using pits, we had to use rtl-sdr and an antenna to receive the radio signal, but it seems like for the flextrak, it uses lora and as such, we can no longer use radio to track the weather balloon. For more specifications I am using the flextrak stm. Due to this reason I was wondering if there is any way to make the flextrak send the signals bya radio, or what should I do to get it working.

Oh and also, the code from Dave Akermans github seems to be a bit outdated due to Picamera2, can any of you help me with fixing some errors?

Thank you all!

PS: Sorry of these types of things get asked a lot.

[Mika Köching]

Hi! Even though I don't have much experience with Pits/Flextrak I will try to answer your question.

To receive LoRa you should use another LoRa device (eg. rfm98w). You can either hook it up to an Arduino or another Raspberry Pi. David Akerman has some examples on his website.

https://www.daveakerman.com/?page_id=2672

Hope that helps.

If you want to transmit images, I'd suggest going with wenet. It's a lot faster than LoRa and also gets regular updates.

[Lucas Castillo]

Hey thank you for responding! I would prefer going for wenet, but I am just not sure if flextrak + raspberrypi can send the radio signals since the only documentation I found only covered using Lora. So, I guess my question really is, how can I send radio

--
You received this message because you are subscribed to the Google Groups "UKHAS" group.
To unsubscribe from this group and stop receiving emails from it, send an email to ukhas+un...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/ukhas/160191de-be3f-4a43-acd1-e0e88dc536d7n%40googlegroups.com.

[Lucas Castillo]

Hey thank you for responding! I would prefer going for wenet, but I am just not sure if flextrak + raspberrypi can send the radio signals since the only documentation I found only covered using Lora. So, I guess my question really is, how can I send radio signals using flextrak + raspberry pi?

On Wed, Jan 22, 2025 at 3:51 AM Mika Köching <mika.k...@gmail.com> wrote:

--

[Ross G6GVI]

Hi Lucas,

LoRa is an excellent radio transmission system: tens of milliwatts in the 434MHz ISM band can be received at ranges of 400km.

As well as HAB telemetry & pictures, it's also becoming popular for terrestrial APRS in the 70cm Amateur band.

Reception doesn't need a fancy SSB or SDR receiver, just a little PCB like one of these: https://www.ebay.co.uk/itm/394293319672 hooked up to a Raspberry Pi or an ESP32 board. There's more information on my web-page: https://qsl.net/g6gvi/habtracking.html

Regards from Ross.

[Mika Köching]

I couldn't find any info on using the flextrak in combination with an rpi online. If you'd like to use Wenet, I'd suggest using the Flextrak in standalone mode. LoRa is quite robust and there are a few receiver in the UK. In Germany LoRa isn't common for HABs. It does seem support APRS and RTTY as well. Those aren't as robust as LoRa but you can use an sdr or ssb radio to decode them.

I personally would use a reprogrammed RS41 radiosonde sending out Horus V2 and maybe APRS together with the Flextrak running LoRa. Horus is really robust and can be easily decoded with a Laptop/Rpi + SDR/SSB-Radio.

Just a quick warning: The signal for Wenet has to be quite strong so be prepared to use a rather long Yagi.

Greetings, Mika