OK I think I have solved my problem.
Combination of two things.
one: need EPLRS equipped JTACs now so I changed the units I was using to ones with EPLRS.
two:In previous build I could contact JTAC whilst still on the ground and receive data. in the new build it seems that there is a weight on wheels block on data.
After takeoff SADL kicks in and data will come through to the TAD.
Works for me now I understand changes.
thanks for the ideas guys.
Bungle I read that the co-ords miles away problem can be caused by the cursor in the TAD being far from your aircrafts position when you are talking to JTAC.
Worth trying.
GH