I spoke with my avionics guy today and discussed the possibility that the problem is due to exhaust pipes shielding the signal; he says that in light of my experience on the flight to Kitty Hawk (see http://cirruspilots.org/cgi-bin/wwwthreads/showthreaded.pl?Cat=&Board=nmqa&Number=8528yesterday’s post), it seems likely. As far as he knows, the Approach Control Radar is in fact co-located with the facility, so that makes sense. I will wait for a little more supporting data before I contact CD to pursue this further.
The problem I experienced (only 8 records of engine data available for download to my PC) turned out to be a bad SRAM card. ARNAV not only sent me a new one overnight, but also sent me a new version of the software, addressing some of the other issues I had raised.
So far, I have tested the SRAM card and it works fine; I haven’t had a chance to fly, so stay tuned for more on the newer software. Although I was pretty disappointed in the PC software, I have to say that their support so far has been top notch.