Why is your HDTV signal interrupted when a train goes by and how can it be fixed?

As usual, the question's a bit too general in nature to supply you with a very specific answer, so I'll use some general replies in hopes that it'll help alleviate your problems.

If you're talking about the reception of HDTV signals over the air as in, I have an antenna on the house and I'm watching a local TV station in HD', the signal you're receiving most likely is in the UHF range. UHF signals are very easy to block and they're also prone to reflections off of another surface and can be delayed, or phase shifted' enough to cancel out the primary signal, thereby killing your TV picture and sound. Even a tree blocking the path, after a period of rain where the leaves have re-filled themselves with moisture can block the signal.

If you have a satellite TV system and you have your dish mounted in such a way that a train may pass between your dish and the satellite signal, that's sufficient enough to block the signal. And yes, you can have some of the same reflection issues with a satellite dish as you would with a UHF TV signal.

The answers are: 1. Raise the level of the antenna or dish. 2. Relocate the antenna or dish. 3. Susbcribe to cable. 4. Just live with it.