Originally Posted by gemma10
Am I being dim here or what. If the transponder is broken, what is the purpose of entering 7800.
Originally Posted by worrab
Didn't you cover this one for your RT exam?
As a noob here, I can only assume that you set it to 7800 if you cant confirm its working?? At a guess, no confirmation from an ATC? Time for me to do some more reading I guess!