I got a question specifically involving this station but maybe someone can tell me the answer if you know of a similar situation
Channel 62 WJYS Hammond / Chicago has it’s transmitter in Tinley Park, IL in Chicago’s South Suburbs. Now Ch 62 is a full power UHF station. But the signal doesn’t reach. Now the took a Low Power TV station (LPTV) Channel 34 Arlington Heights in Chicago’s Northwest Suburbs and put the transmitter on the Sear’s Tower. So because of the great height Channel 34 the LPTV is coming in strong.
Why don’t they just put the full power Ch 62 transmitter on the Sear’s Tower??
Other stations like WPWR Ch 50 Gary/Chicago or WGBO Ch 66 Joliet/Chicago have their transmitters on either the John Hancock or Sear’s Tower even thought their city of licence isn’t Chicago so that can’t be the reason.
I don’t live in the Chicago area and I don’t know the politics of the stations liscensing or coverage agreement with the FCC, but here’s a guess. It’s usually stipulated in your application for broadcasting liscense as to the area that you want to broadcast into, and where your transmitter is located. From this info the FCC allocates your transmitter power, the antenna height above average terrain, the beam width (360, 180, 90 or whatever degree) and the down tilt of the antenna. All this in order to keep the broadcast signal in it’s intended coverage area. So the channel your looking for might be intended for only a certain segment of the Chicago area, or attenuated in a particular area as not to cause interferance to another station in an outlying area.
I can’t find a current chart, but I remember that, because of interference concerns, UHF stations have to avoid causing interference with other stations within +/- 5 channels of their own. Thus, if channel 66 got to downtown Chicago first, channel 62 would be required to place its transmitter a few kilometers away to avoid causing interference.
I think Doug Bowe missed the point on my thread. First there is no such thing as a “full powered” station or a “city grade” signal. You the broadcaster go to the FCC and tell them the area you want to cover, then show them your suitcase full of money. They, (the FCC) then dictate to you, (the broadcaster) the conditions of your signal,ie: power level, available frequency, antenna directivity (the actual coverage pattern, including nulls in certain areas to avoid conflicts with other legally licsensed broadcasters) etc. For more info on this I would suggest this link, http://www.fcc.gov