Well, a 6 dB boost would double your range, IF you aren't
hitting the limits imposed by your radio horizon.
_____________

Clarification: the coverage AREA doubles for the above situation, but the
"range," or distance from the transmit antenna to a given field strength
value increases only by about 40%.

Here are the numbers, using the FCC's F50,50 curves for UHF NTSC TV
propagation.

50W ERP from 100 feet above average terrain:

60dBuV/m at 2.99 miles
Coverage area within the 60dBuV/m contour = 28 sq miles

200W ERP from 100 feet above average terrain (a 6dB ERP increase from the
above example):

66dBuV/m at 2.99 miles
60dBuV/m at 4.2 miles
Coverage area within the 60dBuV/m contour = 55.4 sq miles

The radio horizon for these examples is located about 14 miles from the
antenna site (at a 0.15 degree depression angle).

RF

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