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Discussion Starter #1
Hi,


Can anyone give me recommendations for an OTA antenna so I can pick up HDTV signals? I would prefer real experience with viewing HDTV signals, rather than citing marketing blurbs from Terk's most expensive antenna. I am willing to spend the $$ for a high-end Terk, but only if the results are worth the extra expense.


Note: That I would prefer to locate the antenna indoors to avoid having to mount it to my house and run wires.


I just bought this puppy and should be picking it up today or tomorrow. I can't wait!
 

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Well, I wouldn't go off and buy an over-priced, underperforming TERK antenna just yet. :)


First thing, you need to find out what stations in your area are doing DTV. Second, find out how far / what direction they are from you and what the recommended antenna is (and don't be surprised if it turns out that it needs to be a roof mount). You may also want to get a rotor if it turns out the transmit towers are in different directions.

www.titantv.com can help on the digital stations, and www.antennaweb.org can help on location and antenna recomendation for all stations close to you. (titantv also does antenna recomendations, but they are pushing one of their sponsors). Once you have a color code / size / amplifier recomendation, go shopping. http://www.starkelectronic.com/allant.htm has a good selection of antennas and other supplies if you are a DIY'er. At the very least, once you check out these other sites, you can talk intelligently with an installer.


Finally, be sure to use a good grade of RG6 coax cable to connect the outside antenna to your STB/TV.
 

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I have a UHF/VHF antenna in my loft. It works OK. Outside is better. After getting the info as described above, you should be able to make a fairly informed decision.


Line of sight to the antenna(s) is the most critical. If you have this, the rest is easy.
 

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I recently installed an OTA antenna for my 34XBR2 in the attic. Just got the biggest Radio Shack outdoor yagi that would fit in my attic, and added a channel master preamp:
http://www.channelmaster.com/pages/ss1.htm

It's working great. All my OTA stations are in the same direction, so no rotation of the yagi is necessary. It would be a problem if you needed to rotate it.

Fred
 

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TedGYZ,


Save your money and ignore the Terk. It's only good for metro areas where you're less than 10 miles from the transmitters.


Are you interested in only digital channels? If so, then a UHF only antenna is the way to go. If you're in southern NH, you'll need a fringe antenna if you want to pick up the Boston stations. A Channel Master CM-4248/3021, or possibly a Winegard CA-9095 or -9085 will probably work without a preamp.


Check out Stark Electronics , or better yet, check out the following thread about the Mt. Wilson area in So. Cal.


The antennas I mentioned above are all less than $100 (the 4248/3021 and the 9085 are less than $50), and all have high gain (>10dB more than a Terk with no amp*) and are highly directional, reducing the effects of multipath interference.


*Most Terks are just dress-up folded dipoles with a built-in preamp. If you feed a preamp noise, all you get is more noise...
 

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jonlgauthier,


I don't want to confuse Ted with this statement. But there is a technical inaccuracy in your statement "If you feed a preamp noise, all you get is more noise".


The issue that must be considered in real receiver performance is the effective noise figure of the receiver (TV tuner). I don't know what that number is for DTV tuners, but I'm guessing it's in the 6 to 10 dB range. If you put a preamp in front of this TV tuner, the noise figure of the preamp will dominate (assuming the preamp gain is high: greater than about 12 dB).


Here is a good example:


No preamp

cable loss (RG6) = 5 dB.

DTV tuner NF = 8 dB.

Effective noise figure = 13 dB. Therefore all incoming signals have 13 dB more noise than straight thermal noise (KTB). This is not good for weak signal environments.


With 10 dB preamp

preamp gain = 10 dB. Preamp mounted between ant and cable.

preamp NF = 2 dB.

cable loss (RG6) = 5 dB.

DTV tuner NF = 8 dB.

Effective noise figure = 5.42 dB. Not bad.


With 16 dB preamp

preamp gain = 16 dB. Preamp mounted between ant and cable.

preamp NF = 2 dB.

cable loss (RG6) = 5 dB.

DTV tuner NF = 8 dB.

Effective noise figure = 3.14 dB. Looking real good.


With 22 dB preamp

preamp gain = 22 dB. Preamp mounted between ant and cable.

preamp NF = 2 dB.

cable loss (RG6) = 5 dB.

DTV tuner NF = 8 dB.

Effective noise figure = 2.32 dB. Real low :)


Notes: this simple linear calculation does not include the effects of overloading causing IMD problems.


If anyone out there is interested in these cascade RF calculations, send me an email. I have some good Excel spreadsheets I can share. I'm an RF design engineer.
 

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Discussion Starter #7
Wow! This forum is great.


As soon as I get my TV delivered and hooked up, I will post a review. Is anyone interested in a review of the Samsung SLK407W?


I'm also going to try to find the right antenna. I have lots of reading to do. It looks like Stark is a great supplier. Do any other retailers carry these products?


QUESTION: How effective is mounting an antenna in my attic? I'm going to catch a lot of flack from the wife if I try to mount some beast on the roof.
 

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That depends on what your house is constructed of. In general, you won't get the same performance in the attic that you will outside.


My attic is useless - the skin under the cedar siding is the foil covered stuff - totally kills most RF.
 

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I live in the Chicago suburbs and have the Sony KD-34XBR2. I am approx 25 miles from the two transmitter locations (Sears Tower and the John Hancock Bldg). I receive OTA HDTV broadcasts using an inexpensive ($39.95) Radio Shack antenna without any amplifiers or other gadgets. The antenna is a fairly large, aluminum, yagi. It is currently draped over a couple of chairs in my living room and for DTV, it seems to work perfectly. For DTV signals, it appears that you either get them or you don't...no in-between like snowy or ghosty pictures. My intention is to mount the antenna on the roof in the next week or two. Although there is actually very little HDTV content OTA at the present time, what there is comes in perfectly...stunning in fact. By this coming May there will be five more stations broadcasting DTV per titantv.com. So my suggestion is: don't waste money on expensive antennas if you live within some reasonable distance from the transmitter(s). The antenna does not know if you are receiving digital or analog....it needs to be capable of UHF and VHF.


Al Jennings
 

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Pardon my ignorance everyone, but all of this talk of OTA HDTV with antennas is assuming you have a STB, right? I'm just wondering because I'd like to get some "free" OTA HD programming, but want to wait until the prices go down a bit on the boxes. Right now I have Comcast Basic Cable and am not sure I want to switch over to DirecTV or Dish. So basically, can I get OTA HD programming with only an HDTV, an antenna of some kind, and NO STB??

(I know, I've been on this forum long enough to know the answer to this, but I'm slow sometimes, humor me!:D )

P.S. I live about 5 miles from where the WTC used to be and near the Empire State Building, so I guess I'd be able to get a few metro signals.

Thanks
 

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The Sony KD-34XBR2 HDTV Television set has a built-in HDTV (ATSC) tuner so with that particular model, you do NOT need a set top box. This is also true for the new 57" and 65" Sony XBR projection TV's as well as the older 34HD1 TV from Sony. The RCA 38" TV likewise has a built-in HDTV tuner. I think the sets that call themselves "HDTV Ready" usually do NOT have built-in tuners, so with one of those, you would need the STB. Some people prefer the sets w/o the built-in tuner to protect them from possible future changes in the HDTV broadcast modes.
 
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