How to Split a Cable TV line

Careful: Most cable companies will offer separate packages for cable TV and cable modem service. In order to connect a TV to the cable TV line, you need to sign up for a cable TV package with your cable company. If you don't, your cable company may prosecute you. In most cases, you will not be able to receive any TV channels anyway without signing up for a TV package.

If you sign up for a cable TV package and cable modem service, the installer will setup your PC and TV. If you do it yourself, there are a few points you need to take care of:

Use the right splitter. Ask your cable company which one you use. In many cases, the cable company will provide a splitter. If you chose to buy your own, get one with sufficient frequency range. The range should be printed on the splitter. 5-1000 MHz should do it. The splitter should provide EMI isolation. Only place one splitter between the point where the cable TV line enters the house and the cable modem/PC (see picture on the left). If you have multiple TVs, split the line between the first splitter and the TV, not the line between the splitter and the modem. Do not use any amplifiers in the line leading to your cable modem. Not only do most amplifiers only amplify incoming signals, while your cable modem receives and sends signals, but they are also likely to distort cable modem signals.

only one splitter to the modem! green: right connection, red: wrong