Yagi or omnidirectional

MUTNAV

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It looks like I need a yagi with 13 or 14dbi, less than that it's in red
I love on the antenna tilt, it's negative for both sites...

When in a foreign country, I noticed that the TV antenna on the roof of the place I was staying at was tilted downwards by a very noticeable amount, I offered to straighten it out, and was promptly scolded by the owner that it was set for the best position. I then looked around and ALL of the rooftop antennas were tilted down by a significant amount. It made me think about the real radiation patterns of yagis and if in the vertical plane, the maximum gain is not generally in the exact same line as what the physical layout of the antenna would suggest.

Thanks
Joel
 

Ubbe

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Stockholm, Sweden
I noticed that the TV antenna on the roof of the place I was staying at was tilted downwards by a very noticeable amount, I offered to straighten it out, and was promptly scolded by the owner that it was set for the best position.
I've tested several yagis and pointed them for maximum signal and has always been straight vertically to the horizon. Maybe those downtilted antennas where too close to the tower and needed the signal to be reduced, both the direct signal and any unwanted reflections. TV's usually have rubbish receiver quality that easily overloads. Many user also, like some scanner users, thinks that more signal are better and might use high gain amplifiers and perhaps all antenna systems where installed by the same misinformed guy that where their local "expert".

/Ubbe
 

Bonkk083

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This line of site doesn't make any sense I can get a tower 20 miles away with the scanner on my table with a rubber duck antenna and there's no way it's in line of sight
 

MUTNAV

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This line of site doesn't make any sense I can get a tower 20 miles away with the scanner on my table with a rubber duck antenna and there's no way it's in line of sight
Whats the elevation of the tower, and you?

Radio line of sight is a little longer than visual line of sight. (use the scada site to get the physical landscape elevation, then add antenna heights to that.

Personally, I think that troop-scatter effects are underestimated, but that's a personal idea.

Thanks
Joel
 
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