# Ota



## cbeckner80 (Apr 19, 2006)

I know this may be a stupid question, but it's been so long since I've used an antenna that I'm pretty ignorant about them. I'm thinking of installing a CM-4228 to receive the Atlanta HD stations. I live about 35 miles or so east of Atlanta.

The major problem are trees. One is about 5 feet to the side of where the antenna will be mounted, while their are several in the LOS of where i will mount the antenna. Will this cause problems with picking up my Atlanta HD Stations.

Thanks for your patience


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## nostar (Jun 22, 2003)

Looks like NBC WXIA is digital on VHF channel 10. Although the 4228 has some ability on high VHF it was designed for high gain UHF reception. 

Don't forget the CM 7777 mast mounted amplifier. With about a 30" mast, I think that you will have no problem at 35 miles.

I live 40 miles from Gainesville Florida, use the CM 4228 and CM 7777, and have no problem receiving their digital signals, even though several Oak and Pine trees are in the LOS.


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## Michael P (Oct 27, 2004)

Trees are only an issue for the extreme fringe areas of UHF signals. If the station is running full power you shoud be o.k., OTOH if the stations are still running on low power "STA" or "CP" mode you may have some problems.


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## cbeckner80 (Apr 19, 2006)

Thanks for the information. That is encouraging. You can’t beat these forums for the wealth of knowledge available.

Carl


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## Tower Guy (Jul 27, 2005)

nostar said:


> Looks like NBC WXIA is digital on VHF channel 10. Although the 4228 has some ability on high VHF it was designed for high gain UHF reception.


The performance of the UHF only 4228 is better on channel 10 than any other VHF channel. It's worth a try.


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## generalpatton78 (Dec 17, 2003)

I have a analog VHF 12 thats about 40 miles away and it comes in great with my ch 4228.


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## kenglish (Oct 2, 2004)

You can buy a single-channel VHF antenna, or a high-band (7-13) VHF antenna, and combine it with the UHF, using the appropriate multiplexer.

Either would be smaller than a full-band VHF antenna, and would give a better signal than using just the UHF, which would have a very screwey pattern on VHF.


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## texasbrit (Aug 9, 2006)

The CM4228 is one of the few UHF antennas that has good performance on hi-band VHF. I am 40 miles from a VHF station transmitting digital on 9.1 and get a very good signal, also on the analog channel 8. By the time you get down to channel 5 the antenna does not perform at all well! I use a CM7777 preamp also...


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## kenglish (Oct 2, 2004)

cbeckner...
Got your PM, thought it might be better to elaborate here, for all.

The VHF channels are actually two bands (or, even three, depending on how you look at it).....2-6 are between 54 and 88 MHz (just below the FM band), and 174 to 216 MHz. There is also a small gap between 4 and 5.

Since there is such a difference in frequencies, the sizes of the antenna elements and their spacings are vastly different as well, between low-band and high-band channels. So, a high-band VHF antenna is less than half as big as a low-band antenna with the same amount of gain.

If you are going to only need UHF and the high-band channels (7-13), you can save some space and wind-loading by using a high-band antenna with the UHF antenna. Of course, if any desired stations are low-band, or if you want distant FM band stations, you'll still need a combo (low and high).

A single-channel antenna would work, and would have a little better gain and sidelobe (off-axis response) pattern than anything else....but only on the specific channel. It is probably easier to find a high-band (7-13) antenna, though. And, there won't be a whole lot of difference between the two. Cable systems and translator sites use single-channel antennas for reasons of getting very long-distance reception and for tricky paths.

Places that sell pro stuff, like Blonder-Tongue, have multiplexers that can combine different bands. They are basically a splitter/combiner with filtering built in (2 in/1 out). Cost is usually about $20-30 each. They come as low+high, or VHF+UHF. You could get away with a VHF+UHF for this. Add a low+high in the input of the VHF jack and put an omni-directional FM antenna (FM stations are usually scattered out in many different directions) on the mast, and you would be set for pretty good FM reception as well!

Although you can get a VHF signal on a UHF antenna (and vice-versa), it won't necessarily be as good as you want, since the gain/directionality and sidelobe response is specific to the design channel. That's where you can get in to issues with reliable signals...they may cut out at different times of the day, or with different weather conditions.


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## nostar (Jun 22, 2003)

kenglish said:


> It is probably easier to find a high-band (7-13) antenna


http://www.starkelectronic.com/winp12.htm


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