Improve your TV and radio signals with this antenna amplifier from AmpMaster. Mounting it close to the antenna reduces signal noise. It includes a power injector that simply plugs into a standard mains AC 240V wall outlet and transmits power along the antenna cable up to the amplifier, which gives a boost to the antenna signal of up to 30dB for UHF and 20dB for VHF. The amount of gain can be adjusted using the small control knob on the device.