AVS Special Member
Join Date: Jan 2000
Location: Salt Lake City, UT, USA
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In would be interested in knowing how they measure their overload specs. Many of the domestic ones rate overload (IM3) at, something like, "3 channels" or "5 channels".
In some areas, like SLC, you may have well over two dozen channels on the air in the UHF Band (analog full-power, analog low-power, analog translators, digital full-power, digital low-power, and even digital translators....plus, those new non-broadcast users that are starting to show up).
As you add channels, you de-rate the spec by almost 3 dB every time you double the number of stations. So, if rated at, say "+47 dBmV at 3 channels", that becomes +44 at 6 channels, +41 at 12 channels, ..........
Ken English, Sr. Engineer, KSL-TV.
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