Single engine, single crew, IMC, no autopilot
my technique (as taught by a great instructor)is stanby-scan-twiddle-scan-twiddle-scan-check-scan-squawk and txpndr only goes on during after take off checks to avoid unnecessary garbling in the circuit area. Probably very different in Class A and a Jumbo but that's my twopenneth. ATCOing at a non SSR unit, with lots of puddle jumpers we get lots of calls from D&D about misdialled 7700's