Just like anchoring or picking up a mooring on a boat, hand signals are best. No electronics, no shouting (and cursing!). Just takes a bit of practice and communication, ahead of time. Like at a campground, those already secured enjoy the entertainment with their cocktails,Do any married couples (or other arrangements) use a walkie-talkie (pair) while backing up (to avoid shouting) - if so - what worked and what did not?