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Discussion Starter · #1 ·
greetings all,


I have read many threads on this site that has given me valuable information but there are specific questions that always seem to be vaguely answered or different answers which may not pertain to my situation. So here is my specific question:


1. If I don't have line of sight to the DTV tower, how will I get good reception?


2. Do I need line of site?


3. When I am looking for an antenna purchase, how will I know what is best for my situation? I mean, it appears the CM 4228 seems to be the best for my situation as it has fairly long range(60 miles?), handles multipath? and is recommended by many.


4. Is multipath handled by both antenna and receiver?


5. How well does the DST-3000 handle multipath?


I forgot to mention my situation:


I am approx. 45 miles from the Tower with a mountain in-between myself and the tower. Others say they get a signal which is why my first question asks about line of sight. I am about 10 miles form the mountain but it really isn't that high. I am about 800ft above sea level and the mountain probably isn't much higher than 1200ft(just a guess though). I live in the middle of a valley so there is no other obstructions.


Sorry for the long post and thanks in advance for the help.


Dave
 

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The reason answers to antenna questions throughout the threads vary and seem vague is because of all the variables you outlined in your questions about your specific installation. I notice people ask questions like "which HD antenna is best for Phoenix" and the like.


There is no one answer to questions like these and yours. With dish installation I can guarantee reception if there is clear sky. No such luck with over the air digital or analog. Early on in my DSS installations I installed a lot of VHF/UHF combo antennas (usually Winegard CA-8082) because Direct TV did not offer local channels. With those antenna installations usually there was one channel I had some problems with due to the foothill area I work in. A little ghosting or other interference on one station or another. It was always on the stations the customer claimed they wanted the most.


These days I usually install the Channel Master 4221 90% of the time because most of my work is HD. A great small, inexpensive antenna with gain and high customer acceptance. The bigger excellent 4228 offers probably 5 % to 10% more signal, and the 4248 even more signal but it is pretty huge, is *extremely* directional and cannot be pointed easily without a portable signal meter, and has a dismal customer acceptance record. It is also very sensitive to vertical height where the 4221 and 4228 don't seem to be as much.


Here are some specific and non-vague answers to your questions.


1. You can get perfect reception of all digital signals without line of sight. Sometimes.


2. No. Usually.


3. The Channel Master 4228 is an excellent antenna for HD UHF reception. I do not know of anything really better that I have used.


4. I have no way to measure multi-path, I only have a simple Sadelco UHF/VHF signal meter so I can find Mt Wilson through the smog here in LA and make relative comparisons of antennas and locations.


5. The Toshiba receiver is good (same model as the Hughes and Mitsubshi) but I have seen several fail completely due to overheating in confined cabinets. Install a fan it is gets very warm. I have no way to know how it handles multipath situations.


My general recomendations for antenna installation for the best results.


Don't consider an attic location or indoor location. Rather, put the antenna up on the peak of the roof on a 5 or 10 foot mast. Keep it away from metal flashings, chimney sheet metal as far as possible. Use RG-6 cable with good quality ends like Snap-seal, etc. Stay away from Diplexers unless you have experience with them and have a way to trouble shoot their use. Try to keep the antenna from facing right into a big tree, it cuts the signal way down and when the wind blows the signal will pixtelize.


These general recomendations will help you get a lock on as many stations as possible. Just go for it.


 

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Helevitia,


Neilneil has given you excellent answers, so I'll try not to duplicate.


I don't know exactly where you are in the Bay Area. I'm in the East Bay, about 40 miles from the Mt. Sutro tower in San Francisco. I've done a lot of experimenting with antennas for HD.


The 4228 is the best I've found so far. It will certainly require a rotor because it has a very narrow beamwidth. Even stations transmitting from the same tower (Sutro) can require different aziumth headings.


The Tosh DST3000 is ok for multipath, but not as good as the Samsung SIRT150. The Samsung does not have any satellite receiver, if that matters to you. None of the currently available OTA HD tuners is good enough, in my view, for situations such as mine (and yours) where there is lots of multipath due to intervening, nearby hilly terrain between you and the transmitter. Over time they will get better.


You may find that adjusting vertical angle of the antenna will help aid reception. As neilneil noted, the 4228 is not as sensitive to this issue as the 4248.


The problem is that each situation is unique - you end up having to use trial and error techniques. Small changes in antenna location, height, azimuth, and angle can make the difference between no reception at all and solid reception. You have to start with something reasonable (like the 4228 up about 30 feet, a rotor, a good CM or Winegard preamp, RG6QS cable) and hope it works ok. If not, you have to experiment.


Hope this helps.


Les
 

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Discussion Starter · #4 ·
Wow! Thanks for the great answers from both of you. I only have one more question and then I think I'm ready to spend money on a technology that may or may not work, lol!


First off, I live in Livermore, so not too far from you Les but I am further from the Dublin/San Ramon hills.


question: Do I really need a 30ft! antenna??? Since I am further from the hills/mountain than you are, wont that help reduce the height? Also, what about FCC laws that state you may not be able to put it higher than 12ft? When is that applicable?


Thanks again for all the help.


Dave
 

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Given your distance I would also suggest a pre-amp at the antenna, not a line driver or a distribution amp, a pre-amp 5db to 10 db gain is enough. I have posted on this site, also on my web site under antennas, a procedure for using an analog TV and analog TV signals for pointing your DTV antenna.


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Jim Burns
www.dtvconsultants.com
 

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You should have an easier time of it because you're further east than me and thus not as close to the intervening major hills. However, there are some hills in Livermore and it will not help if you're on the opposite side of one.


The FCC rules allow you to put up a TV antenna up to 12 feet above the roofline. Use two 5 foot masts with a rotor in between and you're fine. Most roofs are at least 20 feet or so high, so that gets you to 30 feet pretty easily. Lower heights may or may not work - again, experimentation may be needed. If you're not completely comfortable doing this kind of roof work, hire someone who is.


I do agree with using a preamp. Probably the Winegard AP4700 would be best in your situation (to reduce the chance of overload from strong local stations such as those on Mt. Diablo).


You can probably get Sacramento stations as well with this set up.


Les
 

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Dave, being in Livermore you also might consider pointing your antenna to the NNE and see if you can pick up the Sacramento/Stockton stations. They all transmit from an antenna farm in Walnut Grove. They're a little further away from you but it might be worth a shot.


Steve


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"We are confronted with insurmountable opportunities!" ... Pogo
 

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On a related note, I am currenly living in an apartment

in Sunnyvale, CA and would like to start receiving HDTV.


Has anyone tried this in the area?


I also have a house in the Sacramento area and tried an

interior antenna there with mixed results. I eventually

shifted to a small roof antenna, with great results.


My first floor apartment is essentially facing the courtyard, so it is surrounded by other three story apartment buildings. I have a small angle from the patio with southern exposure that might work for DirectTV, but I

really only want local HDTV.


Is it worth trying analog UHF reception as an estimate for

the signal strength from the Sutro tower?
 

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I live 40 miles north of Atlanta with many obstructions including a 1900' foothill. My reception depended more on location of the antenna rather than whether it was on my roof or in my attic. I actually had better reception in my attic than on top of my roof with one Wineguard and a ChannelMaster Bowtie I tried. I would also recommend a Channelmaster pre-amp. I have two antennas both with pre-amps. One is specifically built to pick up CBS because the other antenna could get it. Good Luck!


[This message has been edited by bmello (edited 09-25-2001).]
 
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