Anyone remember a film/tv episode set in 70′s US about a radio that communicates with a WW2 **** sub in USA?

Carl asked:


It may have been a Twilight Zone or something but a search of episodes on the internet has drawn a blank.

The rough plot as I remember is that a teenager in modern day (ie. 70′s at the time) finds/acquires a vintage shortwave radio. He begins to listen to the radio and over a period of time he receives messages that appear to come from a german sub bound foudn the USA in the early ’40s. He does some research in a local library and manages to find some information about the supposed submarine and a secret WW2 mission. Still believing it to be some kind of hoax he starts to send messages to the vessel on the vintage radio. The boat changes its mission. I cant remember the ending, but if memory serves, he leaves his bedroom having sent his last message to find his parents home changed, it looks similar but the TV is broadcasting programmes in German and I think a police man comes to the house in a 70′s looking police uniform but with a swastika armband. (To be honest I may have gotten the ending completely wrong!).

I would be very keen to track down what this fild or tv episode was. Any ideas?

Many thanks

Carl