Altitude data from 10/19/2013 Amesbury flights

I got lots of altitude data today, including some via live telemetry from the XBee onboard the DX3. Here's the rundown:

First, here's a reproduction of the telemetry plot (I don't yet have the ground station software rendering the plot to a PDF but I do save the transmitted data to a file, so I created this in Excel.):



I was receiving around 20 data points per second at 9600 baud, no trouble with the hardware or software keeping up with that. The spike is the apogee event, but it's not a real altitude data point, just the altimeter responding to the jolt of the ejection. I like that you can see in the curve the 'bumpy ride' of the drogue-less drop down to 500ft and then the smooth ride on the main down to the ground.

Here's data on all flights. Low power data is from the Jolly Logic II:

Rocket Name	Motor	Takeoff weight	Altitude
Super DX3	CTI 276H152	2936g (6.47lb)	839ft
Super Alpha	C6-5	128g (.28lb)	287ft
Deuce's Wild	2xC6-5	134g (0.29lb)	499ft
Tartar	C6-5	154g (0.34lb)	219ft

Fun day today, by the numbers!

- Matt

Nice! Ill have to check out your dx3 next time. It may be my next build.

It's a great choice John, especially if you are just venturing into HPR. I definitely picked up a few skills while building this rocket.

Back to telemetry, I had a couple of questions from folks at the launch:

1. Which XBees do I use? I'm using the XBee Pro 60mw version. Digi part number XBP24-AWI-001. I get mine from www.sparkfun.com. Claims a 1-mile outdoor (line of sight) range. I've gotten clean data on flights to 1700' so far.
2. What is the frequency of the XBee? It is a 2.4GHz device. A common range for consumer devices (cordless phones are a familiar example of devices in this range).
3. Am I a Ham operator? No, but it is on the bucket list (would open up a wider range of frequencies for my payloads). I do a lot of shortwave listening and of course, fire up the oatmeal box crystal radio from time to time (because I can).

Thanks,
- Matt