Beyond 62

I looked over and over again at some of the products that I saw online. None were meeting my needs.
So this is how I made my decision:

Need: I need a GPS tracker to retrieve the Payload

Optional Bonus: Working above 60K ft ASL would allow me to:

• Follow it in real time
• Record the Flight Path and Max Altitude Reached

Facts:

What if the payload lands in a zone without signal coverage?

• I cannot trust GSM.

Why using GSM in the first place?

• Because it’s way cheaper than any other technology.

Does it work above 60K ASL?

• The GSM transmissions won’t work above a couple of miles high but it doesn’t mean that the GPS of the phone will stop working.
  (Additionally It’s illegal to operate a cell phone in the air)

Will the phone be able to record the flight path and altitude?

• That’s the great unknown. Some people claim it did.
  I am skeptical but have no other solution.

What if the phone dies (bug, cold, battery, hard landing, …)?

• I want a backup system that doesn’t use GSM.

Why not using only the backup system then?

• Because it’s the most critical feature of the payload. For my first flight, I must have a backup tracking solution.

Will the backup system work above 60K ASL?

• Ideally yes, but I haven’t found one able to do it so far.
  It only needs to work once the payload has landed.

Conclusion:

I need two autonomous and independent tracking systems. Each system must have its own power source, GPS and a different communication technology.

Primary system: GPS Phone + Battery Charger + External Antenna (optional)

Backup system: SPOT personal tracker + Track Progress

Details:

An Apple Iphone/Google Nexus One would be a first but they don’t meet the environmental requirements. The GPS Phone can be any GPS Phone that can be powered by lithium batteries. Most people have used the Motorola i290. Activated with Max Cache Size, it seems possible to record the whole flight path.

I will use the SPOT personal tracker for 4 reasons:

1. It uses Globalstar’s communication satellites, it’s not limited by cellular coverage;
2. It works under tough operative conditions (-45C, shockproof, waterproof, floating)
3. It uses lithium batteries
4. I can personally reuse this device for my next adventure.

Both devices should be trackable online through instamapper and spotadventures.

Total Cost: $300

Next: The Camera and Stabilization System!

When I found GPSFlight’s tracking system, I thought that it was it. They provide a complete solution with a GPS Integrated Wireless Transmitter, a USB Base Station Receiver and a Telemetry Software. They include even cooler features like an accelerometer and a temperatures probe.  But most of all they sell a complete turn key solution, hardware and software, working above 60.000ft ASL at rates up to 4 Hz.

I really like their ST900e Transmitter .  I contacted them and each piece or hardware comes in different versions: 100mW, or 1000mW with and without additional options. It seems that 1000mW would provide a safer range than the basic option. But what’s the max distance for a 1W transmitter and 1W receiver? It’s not clear yet. I think that I need a 30 to 40 mile line of sight range. This distance seems reasonable. A better understanding of the performance would be essential.

The cost?  Transmitter+Receiver+Software:

$1430 for 1W

$985 for 100mW

I can’t decide if it’s crazy expensive or a bargain compared to the time that I would need to achieve this on my own. Part of it is because I’d choose the advanced transmitter. The features look really really cool and give me ideas beyond MSP-1/2.

Sounds Great, right?

It is, except that I have an major unexpected money outflow coming soon. The bad news came this week and it makes me rethink my entire strategy. By looking on the market, I found great tools and ideas but I have to keep in mind the goal of MSP-1:  Launch asap a balloon to near space, get it back safely and learn as much as I can from this first experience. BIG WINS!

So even though I kind of hate it, I need to go with the GSM solution that is 10 times cheaper and inaccurate.  Plenty of people made it that way. It also means that I probably won’t have a record of the max altitude reached. I am back at square one but failure’s not an option.