I'm interested in the title and/or author of this story. I was in grade school from 1971 to 1978. The story collections we read were SRA (reading laboratories). Usually boring stuff. But I found back then in one of the readers a short story about a boy who finds an electronic component lying on the ground, and he brings it home and hooks it up to a radio, and that enables him to communicate with a being from another planet. This communication enables that alien-being to save his fellow being who crashed his ship (saucer maybe) on Earth. I'm not positive it was part of the SRA collection.
That would be "The Gizmo From Outer Space" by Keo Felker Lazarus
The gismo that Jerry and Ron have found is no ordinary gadget. It's part of an alien spaceship's radio...and what's more, they must return it. But how?
How do you keep a date with a man from outer space? And when your father asks where you think you're going at 12 midnight, how do you explain?