There are two main types of heat pumps: geothermal heat pumps and air-source heat pumps. A geothermal heat pump draws the heat from the ground, while the air-source type pulls the heat from the air outside.
RF cables are a type of coaxial cable that is used to send radio frequency signals. RF cables are often used to send video information to a TV set. Identification. RF cables can be identified by the connectors at the end of the cables. RF cable connectors have a single pin that plugs into the RF input on a TV or other device and a threaded piece of metal around the connector that can be used to secure the cable to the RF input port. RF cables are commonly used in cable TV and Internet connections.
By Snap, Crackle and Pop on October 15, 2007. An RF modulator lets you connect various inputs to feed into the coaxial cable or antenna input on a television. It's the solution to the problem of having a TV that doesn't have inputs for what you want to connect, or doesn't have enough inputs. So, if you have a video input cable from a DVD or a camcorder, but only an antenna connection on the TV - an RF modulator lets you feed the video to the TV.