Quick Question. I am planning on using the Electron for a near space balloon project in my class. I want to transmit position constantly up to a point. I know it will stop getting GSM signal at some point, but would like a little more details of what to expect in terms of altitude that the cellular antennas can reach. Also What kind of antenna do you recommend I use and if theres any other tips you can provide I would be grateful.
Also, are there any firmware design practices in terms of knowing when theres no signal and attempted reconnects?
As a fall back, do you have any recommendations on a long range, low weight Data-Link transmitter we can use?
I am looking at a couple of options from DIGI. One is a 1 watt transceiver but it is expensive. My bet will be something in the middle with very good tuned high gain antennas. Any help would be appreciated on where to get this kind of antennas for this modules… This is what we have found so far:
I hate to burst your bubble, but in the US it is illegal to transmit cellular data when you are not in contact with the ground. Despite the fact that it doesn’t work very well, you simply are not permitted to do it. However, you can detect when your balloon lands and begin transmitting so you can find it.
I will let others offer their advise on these license-less solutions. They will probably work pretty well. When a device is high up there, line-of-sight and lack of interference works in your favor.
However, another solution to look into is to get your HAM radio license and use the APRS network. Getting your license isn’t really that hard, just read this book and take a fairly simple test. Implementing APRS is a bit challenging, but fun.
The LoRa 900 Mhz radios work just as well as the Digi Xbee 900 Pro modules for a fraction of the cost. You can get many miles of range when you’re transmitting from the sky down with nothing in between.
You can also check out this Satellite Radio Transceiver which others have used also to send data from anywhere in the world.
I would personally just use the Electron considering it’s just a short event and it’s not going to hurt anything or anybody.
I have no idea about cellular and how high it works. The satellite modem product page has user comments stating that they used it high altitude ballone projects if you want to read through it.
Losant back end works with the rock block modem endpoints also so you could use them as your back end data collector and dashboard service.
