Tx only when spoken to

I suspect this request is what someone previously asked about in a "CQ" thread but it seemed to have drifted off that topic, so I'll try to make this clearer. I'd love to see a state in between Enabled TX and No Tx in which it does not transmit unless it is called. This would, of course, be a good way to end a sequence of CQs, where you don't want to keep calling but will answer a call you get even if it is 45 or 105 seconds later, or when you call someone else once but don't want to keep calling unless they answer you, like when they end their current QSO or even work their way down a pile. Maybe we can call this "polite Tx" or "Tx Reply". It's also a way to finish up before going QRT too.

This is the opposite of robot operation, as it requires human intervention to start transmitting again. The previous request was dismissed in part because it sounded too much like a robot.