What is a RF Connection?
RF, an acronym for Radio Frequency, was the first connection method utilized by electronic devices. Early sets were designed to accept only over-the-air transmissions from the local networks, using the antenna on your roof (or atop your TV) to acquire the analog signal. Early game systems had to simulate an actual TV RF broadcast for your television to be able to interpret it (hence the channel 3/4 switch). This type of connection produced varying levels of picture/audio clarity since it is quite prone to interference from a number of other devices.
Connecting your Game Console
There are many ways to connect consoles that utilize this technology. The following diagrams depict not only the history of original setup, but also the most common configurations for both SDTVs as well as HDTVs. Click the pictures to enlarge.
Connecting a Japanese System via RF
Older RF systems from Japan, like the original Nintendo Famicom, work the same way as those in North America, with a caveat - those consoles utilize a Channel 1/2 switch, which are transmitted on a non-compatible frequency with NTSC-U televisions. There are a couple of ways of getting your Japanese RF system to work, but bypassing the TV\Game Switchbox as described above is the way to go in the long run. Using the RCA Phono to Coaxial F connector will provide you with a basic cable output, which then you can route to your television using whatever method you like. This is where is gets a little tricky - what channel to select.