kirk.stant wrote:
What we need is a combination PCAS/FLARM/Transponder...

It's called "ADS-B". Seriously, at the SSA convention, a representative
from MITRE showed a proof of concept cigarette pack size ADS-B UAT
transmitter that is powered by 2 AA batteries. It is currently
undergoing flight testing on the east coast. Constructed primarily
using about $150 worth of cellphone RF components, the estimated retail
cost if produced would be $750 to $1000, and MITRE is willing to license
the design for a nominal cost. A transceiver is currently on the
drawing board. The major problem with this device is that it uses a
consumer GPS receiver module, and the FAA has apparently not given much
thought to the idea of VFR-only ADS-B devices, instead assuming that
everyone will be using certified GPS units at $3000 or so a pop.
Efforts are being made to counter this assumption, hopefully there will
be news on this front in a few months...

Marc