When the device is off the signal gets passed to your television like normal with no difference in the viewing experience. Turning PCTV To Go on lets you capture the video output and stream that to any computer in your house or even across the Internet, as long as it's running Windows XP or Windows Vista.
Connecting a video source to the PCTV is accomplished through one of the component, composite, S-Video, or RF inputs. There is only one set of stereo RCA inputs meaning you have to use a Y-cable to receive audio from multiple sources. As a result of the audio setup only one source can be active at one time otherwise the audio will overlap ontop of each other. Controlling the connected device is accomplished through the included IR blaster that passes remote signals from the computer directly to the source box. The box can accept a high-definition signal, however the media stream is downscaled to standard definition.
Networking the PCTV with the computers can be done through the wireless G connection or a wired ethernet cable or both. However, there are some quirks in the network setup. If your computer is connected to your home network through a wire, then the PCTV must be connected through a wire for the two to communicate. Similarly for wireless computers. Therefore, if your home network contains both wired and wireless computers, then the PCTV must be connected to your home network both wirelessly and through a wired connection.
Pinnacle claims that up to 50 computers can receive the stream at one time. Two notable issues are that the PCTV can only send out one stream at a time. Meaning every computer connected to the PCTV sees the exact same thing. Furthermore, when the PCTV is sending out a stream the signals are not passed through preventing people from watching television on the TV itself.
Pinnacle includes software that lets you view, pause, rewind and record the media stream and control the PCTV box itself. If you have a Media Center PC then you can configure the software to integrate with the Media Center as a television video source itself. Streaming across a local network uses MPEG2 compression which results in higher quality than the MPEG4 compression used for streaming over the Internet. Other limitations for remote streaming include being limited to Pinnacle's software, and no recording capabilities.