These sort of projects can be very rewarding. But be sure to fully understand the hardware and software requirements before you discount using the TL100. I have several hundred dollars invested in my ongoing telemetry project and it is still not done to my satisfaction.

My project has two Motorola pressure sensors (speed and altitude), exhaust thermocouple, ambient temp via Dallas DS1620, rotor head speed via opto detector, three battery monitoring channels, fuel level, wireless RF link, and more. I am now on version II. It has been in limbo for over a year -- not enough hours in a day to get back to it.

If you would rather be flying than developing, then order a TL100. Otherwise, subscribe to a Jolt cola delivery service, crank up the compiler, and go at it. Good luck!