Dbtlss u all undrstd t abv thread's many abrvvns ? I no a phew !
e.g. CAA Mode-S IFR VFR ATC LARS Mode C TMZ
ADSB using ES NATS EASA TBM850s EHS CAT SFL IAS ROC or ROD ROC/ROD GA VSL
A GTX330 will radiate all data connected up to its RS232 or ARINC inputs. GTX330 definitely emits the GS (because his GTX330 is - like many - set up to use GS to switch between AIR and GND modes) has asked Mode S equipped ATC.
Meantime Farnborough RADAR radio in the south east persists in giving a patchy 'service' (I know it's free).
BTW I could instead be happily & foolishly thinking of listening out with a (very) BASIC service on Shoreham, or Goodwood, or instead using SafetyCom, or not bother at all !
That's five categories of communications a lone flyer in free airspace could be into. Surely this simple system could be organised and functioning cohesively for separation, using current bog standard gear, before making all the fuss about expensive esoteric electronic wizardry, with which magic men in "ATC" will somehow ensure the air in front of one is empty !