09-08-2021, 04:18 PM
Unless someone is running a brush type AC-DC appliance, like an old vacuum cleaner, in your house, you will probably not be bothered by RF on the power lines these days, But when these radios were made it was a more common problem. You are right that the caps do also allow RF to go the other way, and can serve as a make shift ground; however, these radios were designed to have a proper ground and antenna. That is why they have a ground terminal. The main purpose at the time of their manufacture was to filter interference from the line.
