Larry Flesner wrote: >>..."mode C was reporting my altitude to within 150 feet of the altimeter >>and dual GPS receivers on board and my little hand held radio with external antenna was loud and clear. <<
Larry, Congratulations! I'm sure you know this already, but keep in mind that GPS altitudes differ from the pressure altitude system that altimeters (and encoders) use. The error grows with altitude. Two GPSs will match pretty well at altitude, but the pressure altitude system that the aviation system works on (and your encoder) is inherently "inaccurate" with respect to reality. But we all use the same system, so it works. I didn't realize this until I had a GPS in the plane and compared it to the altimeter at high altitude and wondered why the difference... Mark Langford ML at N56ML.com website at http://www.N56ML.com --------------------------------------------------------
