How long the cable is.
Modulation is the process of varying one or more properties of a periodic waveform, called the carrier signal (High Frequency Signal), with a modulating signal which typically contains information to be transmitted. The aim of digital modulation is to transfer a digital bit stream over an analog bandpass channel, for example over the public switched telephone network (where a bandpass filter limits the frequency range to between 300 and 3400 Hz), or over a limited radio frequency band. The aim of analog modulation is to transfer an analog baseband (or lowpass) signal, for example an audio signal or TV signal, over an analog bandpass channel at a different frequency, for example over a limited radio frequency band or a cable TV network channel.
270M: -68dBm@10% PER\, 130M: -68dBm@10% PER\, 108M: -68dBm@10% PER\, 54M: -68dBm@10% PER\, 11M: -85dBm@8% PER\, 6M: -88dBm@10% PER\, 1M: -90dBm@8% PER