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Old 12-16-2017, 11:57 AM
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Quote:
Originally Posted by Jeffhs View Post
... One of those is the CBS affiliate on RF channel 19, DTV channel 10...when it converted to digital, that signal weakened to 9.5 kW ERP, causing all sorts of reception problems east of Cleveland, including where I live.
Jeff, you have reversed the description of the situation. WOIO analog was on RF channel 19, with the requisite high power for analog UHF. They are now broadcasting in digital on VHF RF channel 10, with virtual channel number identifier 19. When they went to VHF, they got stuck with the low ERP due to the erroneous VHF planning factors that got baked into the system and did not take into account the level of ambient interference in the VHF band.

A proportionate increase in power of all VHF stations would solve the noise problem without causing added interference between stations, but this is impractical economically due to the number of transmitters that would have to be replaced and commissioned simultaneously. It also involves international treaties regarding interference levels across the Canadian and Mexican borders.

Hopefully this will be taken into better account with ATSC 3.0 broadcasting. It is a tough nut to crack because stations cannot arbitrarily increase power individually without considering interference to other stations that do not change at the same time.
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