The present invention provides combining and separation circuitry, which allows multiple signals in different frequency bands to travel in either direction over a single cable and be combined and separated as desired. In one embodiment, the combining and separation circuitry includes first, second, third, and fourth ports. The first port is configured to send or receive signals in a first frequency band, the second port is configured to send or receive signals in a second frequency band, and the third port is configured to send or receive DC signals, baseband signals, or a combination thereof. The fourth port is configured to be coupled to a cable in which the signals in the first and second frequency bands, as well as the DC and/or baseband signals, can be sent in either direction.