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Grey Hair 74
20-Jan-2015, 4:13 AM
I may not being using correct terms or terminology last time I used a on air antenna was over 60 years ago.. When a station broadcast a signal is that signal coming off the tower flat like a disc or shaped like a umbrella. The reason I ask this question is my location 1998 feet + 20' in elevation and 65 miles west of Knoxville TN. Line of sight east has 2 mountains ranges 200--300 feet higher in elevation than my location ( 38571 ). Knoxville TN is appromatley 800-900 feet lower in elevation. I have read numerous articles claiming the height of the transmission towers at Sharps Ridge in Knoxville I have yet to find real figures. If any one knows these figures please post them and any other information regarding signal strength on this subject.

ADTech
23-Jan-2015, 4:55 AM
All of that data is in the FCC licensing database. http://www.fcc.gov/encyclopedia/tv-query-broadcast-station-search

Some of the data is in formats that are a bit obtuse and require some training to decipher into understandable descriptions and data.

When a station broadcast a signal is that signal coming off the tower flat like a disc or shaped like a umbrella.

I've used the description of "shaped like the cross-section of a toadstool cap" to describe the vertical elevation pattern of many transmit antennas. The amount of "droop" from the horizontal, when used, is specified as electrical beam tilt. Additional beam tilt in a particular direction can be added by mechanical means for areas that require such. Los Angeles has a number of transmitting antennas that have both.

The tower sites on Sharp Ridge are at around 1300' ASL elevation and the towers themselves are up to 1500' tall above that site placing the transmitting antennas around 2500-2800' ASL, depending on the location on the tower.

Please note that the TVFool calculations do not take the vertical elevation profile of the transmitting antenna into account as this data is often not in the FCC database.

Grey Hair 74
23-Jan-2015, 11:37 PM
All of that data is in the FCC licensing database. http://www.fcc.gov/encyclopedia/tv-query-broadcast-station-search

Some of the data is in formats that are a bit obtuse and require some training to decipher into understandable descriptions and data.



I've used the description of "shaped like the cross-section of a toadstool cap" to describe the vertical elevation pattern of many transmit antennas. The amount of "droop" from the horizontal, when used, is specified as electrical beam tilt. Additional beam tilt in a particular direction can be added by mechanical means for areas that require such. Los Angeles has a number of transmitting antennas that have both.

The tower sites on Sharp Ridge are at around 1300' ASL elevation and the towers themselves are up to 1500' tall above that site placing the transmitting antennas around 2500-2800' ASL, depending on the location on the tower.

Please note that the TVFool calculations do not take the vertical elevation profile of the transmitting antenna into account as this data is often not in the FCC database.

Thanks for the information... Just a ole geezer thinking out of the box and trying to be simple figuring 2 mountain ranges between me and sharps ridge. Doing the Google line of sight with the red line and then doing the profile I see one range at 200+ feet higher than Knoxville and about 100 feet higher than my location .. second range is pushing 300+ feet higher.. curious on reception in my area knowing the 2 mountain ranges are in between me and Knoxville..