NEW 24 DB CABLE TV ANTENNA BOOSTER SIGNAL AMPLIFIER 24DB HDTV AMP KF-220 VHF UHF TV Signal Amplifier 24dB High Performance TV Signal Amplifier / Booster FM Trap, On/Off Indicator Warranty: 90 Days Notes: For over the air digital and analog amplification/boosting, you have an existing signal being received by the antenna. If you have no signal to begin with, no signal amplifier in the market today will fix the problem. If the antenna is receiving a signal, amplification/boosting with this unit will cure the intermittent signal loss. It will not work with antennas that are already amplified.