Thanks for the replies.
Regarding the coverage of the radar source he was using, at a similar position in the business jet I fly (albeit at a greater height 4000-5000 against 2500-3000 and with mode s)we get picked up immeadiately. Thats why I chose that particular ATC unit and location for the test.
Also I had given my actual location and height (no mode C), so wouldn't it have been natural for the controller to use the appropriate head?
