Skip to content

Archive for September, 2009

20
Sep

Tracking Antenna Mount

This weekend I’m working on a tracking antenna mount that we’ll be using for our UAV and balloon tests in the next few weeks (months?).

P1010485


Block diagram:

TrackingAntennaBlockDiagram.png

Here’s what’s inside. A MakeController and an alt-az gimbal mount that I don’t think is available any longer.

P1010487


The ports. Ethernet and USB (not sure which I’ll implement) for the ground control computer to connect to, and power (may not be used either).

P1010486


Here are the other parts. GPS (EM-408) , compass module (HMC6352), external GPS antenna (with a little MMCX to SMA pigtail):

P1010489


Closeup of the GPS and compass module:

P1010491


Getting all the stuff mounted in the enclosure has been a pain, and has taken much of the day (plus the Cal game, and other stuff). There’s a lot of wiring to do still, and hopefully I’ll actually get some code written this weekend. Stay tuned!

14
Sep

Launching a Balloon

I’ve seen a lot of reports lately of recent and past amateur balloon launches. People have been launching sounding balloons with payloads containing GPS and cameras, and have been very successful. I’ve wanted to do this for some time, and coming across all these reports has excited me about the idea again.
Really what I want to do is launch a satellite. So I’ve decided to expand the scope of the balloon launch in support of a future satellite launch. I’ve ordered the Microhard radio we’ll be using on the satellite to test on the balloon.
We’re going to build a payload with GPS, temperature, pressure, still pictures, and possibly video. Lots of work to do in the link budget calculation to see what we can do, and within the 1.8-kg payload FAA limit. We’re also building a directional 2.4 GHz antenna to automatically point at the thing (a project I began a couple years ago for UAV use).
This is going to be fun. Check back for updates.

12
Sep

MissionClock Sales

MissionClock has been in the iTunes App Store for a few weeks now, and I thought I’d post some sales information. The chart below shows the relative number of unit sales per day from July 30, 2009 to September 10, 2009. The two big spikes in sales corresponded to the STS-128 launch attempt on August 24, and the actual launch on August 28. Labor Day was particularly bad. There is no data for the dates from August 5 to August 8.

SalesByDate.png

Clearly, launch days are good for MissionClock.

« Older Entries