I have an SVM-22 channel plus, channel modulator that is supposed to be broadcasting to 60 TVs. I have only gotten it to broadcast to about 5 TVs within 50 feet. I need it to go over 200 feet. I have plugged in two 18db amplifiers into the output and that has done nothing. Also there is no sound coming out of any of the TVs . I need help ASAP. Thanks.