IO540
The Narco STARNAV used GPS, VOR & DME, it was a bit like a GNS430 except that you still had RNAV if the GPS dropped off line as long as you had VOR/DME, to this you could also feed Loran data (overkill perhaps). The only Collins RNAV that I remember was a unit that was KNS80 like in function but a lot less intuative to use.
Silvaire1
Correct me if I am wrong but I was under the impression that the ADS-B had to data link via a mode S transponder, if this is so the mode S would hardly be Ancient history + an evolutionary dead end.
Fit the master switch.............. you wont regret it!