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A while ago I removed an Delhi SFA-1483s antenna while taking down a tower. The boom broke when taking it down, but I have some spare boom material that I can remake a boom for it. I am wondering if it's worthwhile, and if so, are there any mods I can make to it at the same time?

http://www.wade-antenna.com/Wade/UHF Antennas.pdf

Specs show 9-12dBd, although no gain chart. Here's what I do know about the antenna:

-all directors seem to be the same width, and are evenly space away from the feed element
-as can be seen from the pdf, there are two smaller booms, one above and one below the main boom. Mine are in ok shape, but could use some tweaking to make them straight again

Is this a decent antenna as a starting point? If it's worth modelling, what dimensions should I measure?

I'm at work now, but can get some real measurements tonight.
 

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That was a very popular antenna in Toronto when UHF stations first popped up in Buffalo. :) I don't think there are many of them left though.
 

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Is this a decent antenna as a starting point?
Keep in mind the 12 dBd (14.15 dBi) top gain is going to be near the old channel 83 area. For channels 14 - 51, most likely the gain will be in the 9 - 10 dBd (11.15 - 12.15 dBi) range. Not too impressive anymore. The CYD-1430 would be an interesting antenna to model.

If it's worth modelling, what dimensions should I measure?
You would write down all the dimensions and spacings and gauges as if you were to build a clone of it without having the antenna in front of you.

-all directors seem to be the same width, and are evenly space away from the feed element
The fact that all the directors have the same spacings and lengths and diameters makes writing them down easier.
However, I believe that if you measure the distance from the first director to the feed element, that distance will be different (shorter) than all of the rest of the director distances.

are there any mods I can make to it at the same time?
Tying on a larger 2" X 4" mesh (or smaller mesh size) reflector to the existing reflector would certainly help the gain, especially for the lower channels.
 

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In the 1970s the Toronto station CITY-TV was on channel 79, hence the popularity of this sort of antenna that held up well into those very high frequencies. CITY used to run what they called "Blue Movies" on certain nights, and people all throughout the surrounding area and in upstate New York bought these sorts of antennas to try to get their fix of free soft porn. :D
 

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I remember CITY's overnight programming quite well. ;)
 

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Keep in mind the 12 dBd (14.15 dBi) top gain is going to be near the old channel 83 area. For channels 14 - 51, most likely the gain will be in the 9 - 10 dBd (11.15 - 12.15 dBi) range. Not too impressive anymore. The CYD-1430 would be an interesting antenna to model.
One of my favorite channels to watch at my DX location is 19, with another being 18. I've always coveted one of those CYD1430s, and see one listed as in stock at ACK Supply in Atlanta, but at the $75 or so they're asking before shipping, it's just not worth it to me.

Now back in the day when they were more available and much cheaper, I'd already have tried one. :cool:
 
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