TCAS or not TCAS?

[CRDedrickson]

Thanks for both of your responses!

What I refer to as ‘active traffic’ is when an airplane with an active XPDR interrogator onboard sends a query which is replied to by another aircraft transponder. I called it ‘active’ because of a transmitted signal from the equipped plane. I understood the Ryan 9900bx (or Avidyne 600) to be this type of system that actively interrogated itself, stimulating a response from traffic.

Other systems may receive transponder signals and give a general idea of location and range based on signal strength and the diversity signals between two antennas. These are passive systems and rely on some other query signal to stimulate the traffic plane’s XPDR.

I believe the L3 transponder has the same function as the Ryan 9900bx when attached to the diversity antennas. My avionics installers think they will be able to do this simply by unlocking the option in the NGT9000 transponder and connecting it to the existing antennas. I guess I’ll find out in April after the Exumas trip, and while recovering from Achilles’ tendon repair surgery!

ADS- B reception dead spots I think are very few over land. I’ve heard that soon the satellites will be in place to pick up these signals worldwide.

I’ve built three ADS-B receiver stations and connected them to the internet becoming part of the ground system. I gave one to a friend in Tuscaloosa, have one in my home in Georgia, and gave the third to my avionics shop last week so they could get registered and qualify to get the commercial version of FlightAware for free.

There were still a lot of dead spots in the VIrgin Islands last time I looked at my tracking station software. I don’t spend much time with the site, but there are a lot of statistics and measures available if you are really bored or just ultra competitive!

Russ
N8CV