I'm looking for an old book, more than 40 years old, almost certainly a lot older, about spaceship heading to some planet, I believe it is Venus.
The previous ships have not been heard from after landing. On the way a teenage boy has a brainstorm that if the planet was surrounded by an electromagnetic field, then the other ships would not be able to communicate with Earth even if they landed safely. They take precautions to protect the ship against this possibility and of course the boy is right. It then describes their adventures on the planet after they land.
The story I'm describing is NOT The Callistan Menace by Isaac Asimov.