I have forgotten to pull up the antenna in the past and flown without incident through an entire flight a few times , only to realize it on my final approach. I sometimes fly quite far out and have been fortunate. Futaba equipment with the Rx tuned to the channel I am flying on. I am from the old school that the crystal gets changed the radio gets retuned. High/low makes no difference as the frequency is right on.

Now for remembering to put up the antenna: I pull it up just BEFORE starting the engine, after I have checked out all the mechanicals and done a range check before my first flight of the day. The range check comes as soon as the mechanicals( pre-flight check) is done.

Steve