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Reception
Bob called to tell me that with the reception of HDMS9100 take a look at these figures. For reception of WJW on channel 8 the NM(dB) is +18.4 and the antenna gain with out the built in preamp is -6.4 so that makes the signal strength 12 NM(dB). The amplifier gain is 16 dB on the VHF channels and then subtract the 3.7 noise figure , making the amplifier gain 12.3 dB. So while it is true that a amplifier does not make signal , the amplifier will at least carry the 12NM(dB) signal from the antenna through the coax with no loss of the 12NM(dB). So 12 , while not a real hot number , it is Ok. . . And then if WJW 21 is on the air , the NM(dB) # is 14.4 . The antenna gain is +2.5 making the number 16.9 . The UHF amplifier gain is 20 dB and then subtract the 2.9 of noise and that leaves 17.1 dB. So the 17.1 dB amplifier gain will at the very least carry the 16.9 signal through the coax to the tv with 16.9 at the tv. The FCC reference point number for reliable reception is 0 NM(dB).
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