How difficult would this be to do? (I have a sneaking suspicion that it would extremely simple as I once had a computer monitor with a “video in” plug on the back.) Would it just be a matter of buying/building the appropriate cable adapter?
I think you would need a TV tuner such as this:
(I haven’t used the product and can’t vouch you on the quality)
Some LCD’s and computer monitors have a built in TV Tuner meaning you could plug a TV straight into it. Most dont requiring you to buy a special card for your computer or buying a video card that accepts TV input. There might also be a discrete version which doesn’t require a compute but I’m not aware of it.
Planar Video EX S-Video & TV Tuner Input Accessory
Expand the Video Capabilities of any Monitor
The VIDEO-EX S-Video and TV tuner accessory expands the video capabilities of any monitor. The S-video input is great for viewing signals from DVD players, VCRs, and video game systems. The VIDEO-EX is easy to set-up and install. It also includes a full function remote control. For viewing TV signals it includes a complete channel auto scan and memorize function.
If you want to leave your computer connected to the monitor, you can just get a TV tuner card for your computer. There are many brands available with varying price and quality. I have an ATI All-In-Wonder video card which combines a TV tuner card with a video card. You can also get a card that just works as a TV tuner.
However it may not look as good as a real TV. I’ve noticed that most computer monitors are darker and have lower contrast than TVs. I have a real TV next to my computer, and broadcast TV looks much better on the real TV.