Last leg of PPL qualifying XC, I've just taken off from the 2nd airfield, heading home, and key the mike for FIS with London Info. No response. Multiple clicking later, I try the other PTT switch - It works. Yay! So I change headsets in mid air, and continue home only using the other PTT switch to make all radio calls.
Finally land, bit stressed, tired, but over the moon. Decide that since it's a perfect summers day I might as well fly some more! So refuel, get the OK, and jump back in, still thinking about how well I handled my first 'comms failure'. Try to start... winding... winding. Ahhh! Mixture's out! A few people are now outside watching me, and this is beginning to look a bit embarassing. Get it going anyway, get to the mag checks, flip the key one way then the other - fine - flip it to the second notch - engine coughs - loudly! I try it again - same happens. Suddenly dawns on me - engines don't run when you switch the ignition off. I'd turned it one too many notches.
Shut down, get out, go in, and drink coffee. Bit red faced, but god only knows what I'd have done next if I'd gone flying. Mistakes I've sure learnt from though!