The A / B switch is a very useful TV accessory that allows two radio frequency / coaxial devices to be connected to one RF / coaxial input. It allows you to switch between the two separate coaxial signals on one display. With RF inputs, not three color-coded RCA inputs , it connects to a 75-Ohm cable.
A / B switches vary in style; some have simple, metal housings, while others are plastic with remote control options.
How are A / B switches used?
Here are three common scenarios in which you can use the A / B button:
- You own an HDTV, subscribe to an analog cable, and use an antenna. Since most HDTVs have a single RF input input, you will need an A / B switch to connect the analog cable and antenna to the RF input of the HDTV. The result would be the ability to switch between the two RF signals without disconnecting the cables.
- You own an analog DTV and use a DTV converter, antenna and VCR. You want to continue watching TV on one channel while the VCR is recording on another. Given that the DTV converter controls the input signal to the VCR, you will actually need two accessories for this to happen: an A / B switch and a splitter. Connect the antenna to a splitter that divides one input into two outputs. The two cables run on separate paths until they are reconnected to the A / B switch. Read more about this scenario.
- You want to watch two camera channels on one viewing display. The output of the camera is RF, so you need a coaxial cable. The viewing display has only one coaxial input. Connect each camera with the A / B switch so that you can switch between the first and second.