Pan call for an alternator failure in VMC? Really? Flew the Cub for six months without a generator while we waited for parts.
Had two and a half engine failures.
One was an elderly motor glider with a pull start, tried to restart after failing to soar and punched myself in the nose when the cable came adrift from the handle. The incentive to soar became quite considerable, in the absence of any field large enough to take off from and the equal absence of a trailer. Scrabbled away and got back home.
One in a C172 in the hold with the student flying. Saw the temp rising and the pressure falling and we landed off the procedure, in marginal VMC. The student didn't actually notice anything wrong despite the oil mist on the windscreen and the odd smell. The engine was still running as we landed and my CFI wasn't best pleased with me for not taking it to the maintenance base twenty minutes away. It got its replacement engine fitted outside...... So that was the half.....
Then the next week I lost a magneto drive on takeoff, which somewhat annoyed the engine as the random sparks perturbed the ignition process. Landed ahead on a nice long runway, while the glider behind avoided running up my tailplane. He probably had the more interesting experience.
None of them involved any radio calls, not that either the motor glider or the tug had a radio anyway but the half failure I suppose could have merited a pan call if I had had any expectation that the fire engine would have started. As it was we didn't need one.
Not that a radio knows anything about flying anyway. Best keep the airframe in one piece then you won't need to tell the ambulance where to find you. I'm not saying it's a bad idea to ask for help, just that the priority has to be fly the aeroplane. Then point it in a reasonable direction, and after that if you think some help would be useful, then it's time to start asking.