Onh Low Noise HDTV Antenna Amplifier Signal High Gain Booster for TV HDTV Antenna with USB Power Supply 15 Miles boost Range and 20dB high Signal Please check what channels working in your place before you place order.If your TV picture is not in high definition, or you can not get the weak signals from far away towers, you can use this amplifier to boost the weakened signals. If your TV picture is not crystal clear, or you can not get the weak signals from far away towers, you can use this amplifier to boost the weakened signals.The amplifier/booster can enhance the signals weakened by the obstructions between you and the towers, but can not add signal Signal in your area is according to local radio area, and the channel receiving will be a little different sometimes, it depends on the distance between the place where you are and local radio tower. Channels in your area is according to local radio area, and the channel receiving will be a little different sometimes, it depends on the distance between the place where you are and local radio tower. We do not suggest you use this amplifier/booster if your house is very close to the broadcast tower and the signal is already very strong. A booster will cause self-oscillate and you may get fewer signals than without.