There are three percentages reported by the HDHomeRun
Signal Strength (ss)
Signal Quality (snq)
Symbol Quality (seq)
The above definitions can be confusing, so a much simpler definition is to imagine listening to the radio:
Signal Strength represents the volume
Signal Quality represents how clearly you can hear the lyrics
Symbol Quality indicates the percentage of the lyrics you could hear or guess correctly
As it turns out, Signal Strength is somewhat irrelevant; if your antenna isn't pointed properly, it doesn't matter how loud you turn up the volume, the static will prevent you from hearing the lyrics correctly. Similarly, amplifying a weak HDTV signal can result in a high signal strength but too much noise to decode the digital data correctly.
Use the Signal Strength for a rough idea of direction, but align the antenna for the highest Signal Quality, ignoring Signal Strength. When aimed correctly, Symbol Quality will show 100%, indicating no errors in the output. Splitters and amplifiers can introduce noise which will lower the Signal Quality, even if the Signal Strength increases.
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