I decided to provide a system overview of the avionics. Here is a picture (this picture may also be found in the files section).
First let me mention that this an early design configuration, this may change over time.
First the cameras will not be connected to the motherboard and there will be no way to stream the photography that they provide live because of that. The images will be extracted from the memory sticks after nearcraft retrieval. They will run until the batteries die, the memory space is used up or the nearcraft is retrieved.
As you can see from the diagram, there is a third camera. This one will be connect to the flight computer. Imagery from this camera will be streamed to ground stations using the radio in another slot. Currently it is expected that about 1 picture a minute will be beamed back to earth.
In a future test I will attempt to measure and document the radio range that the CC112X-2442-MVK module provides. I expect the range to be enough for tracking purposes (as long as the tracking vehicle is nearby) and possible enough range for telemetry (position, data...) to fixed ground stations for most of the trip, but it is likely that live images will only be available to fixed ground stations ( by that I mean a station at launch site) for a limited period of time due to the radio range when using high bandwidth transmissions. The low bandwidth transmissions have a longer range and should be available for most if not the entire trip.
Th RF debug board has a SD card connecter that will be used with an SD card to log all the data from sensors and also from the GPS device for the entire trip.
An AFE breakout board will be connected to a GPS receiver and an AT&T Sony Ericsson T226 cell phone which has a serial AT command interface. With this connection we should be able to send SMS messages from the flight computer. I have done this before a while ago just by experimentation. The messages are expected to be sent when the nearcraft has landed. The phone's SMS capability may be important if the landing location cannot be determined from the radio transmissions. But it too may be limited if the nearcraft lands in a non-covered AT&T area. If that case occurs, it will be up to SPOT tracker to save the day.
In future blog posts I will document an item or feature that I am researching or developing and it is likely that each item will have an in-depth review.