Outdoor antenna setup


I will soon be in a position to install an outdoor antenna on the south west peak of my house. Living in Hartford, CT I am hoping to pull in some Boston or NYC stations. I'd like some advice on the type of antenna to buy and what type of cable to use(coaxial vs flat), the necessity of a rotator and other helpful pearls of wisdom. I will need to run 75-100 feet of cable to get from my antenna to my tuner(Rotel receiver Rx-975). Also advice on alternative tuners considering my location and desire to get stations 120 miles away would be appreciated. Thanks alot. Len
bigo
Several things come into play when installing an outdoor antenna. First, you want it high. Second, you want it where is is not going to get reflected signals, causing multi-path distortion. The peak of your roof is a good place on the roof, because the roof surfaces are angled away from the antenna. If the antenna is on one side, the roof will reflect a second signal to the antenna very shortly after the original signal enters, causing smearing(multi-path). The same is true of large buildings, or other hard surfaces in the nearby area. For pickup of stations 120 miles away, you have a tough problem. First the power levels of many radio stations are not sufficient for distances like that. Second, you are out of the direct signal path, as the signal is directional, and you have 2 degrees of arc(earth's curvature) between you and the station. 1 degree of arc(60 miles) takes you out of Line-of-sight transmission. Therefore you must rely on reflected signals which is dubious at best. A high mast would be the best solution. Anything over 60 miles is considered "fringe area". 120 miles is out-of-range. AM broadcasts, particularly at night, may reach you, if there is no required power reduction of broadcast, as there is in many areas. There is little hope for FM to make it that far. If you are on a hill, and you are getting some FM from those distant stations, there may be some hope. I'll leave the wiring questions for somebody else.
Hello Len. The classic outdoor antenna for FM is Channel Master's Stereo Probe 9, a 9-element directional antenna which has unfortunately been discontinued. The Winegard HD6065 is very similar and is still available for about $75. It should be mounted on a rotor for optimum results. Although 300 ohm twinlead has slightly less resistance, my advice is to stick with a good grade of 75 ohm coax such as RG-6. The coax has much better durability and interference rejection. Twinlead actually acts like an antenna itself and screws up the directional aspects of your antenna, reducing selectivity and promoting multipath interference. Check out starkelectronic.com for great information on antennas and as a source for the Winegard. (I bought my Channel Master from Stark but have no affiliation with them.) You might also check out a company called Antenna Performance Specialties (APS) for higher gain, more directional antennas than the Winegard/Channel Master variety. While the APS antennas offer ultimate performance, they are very large (making installation difficult) and expensive.

Regarding tuners, your desire to receive stations 120 miles away means that you'll need a great one, especially if the stations are crowded together, as I imagine they are in the CT/NYC area. Unfortunately, the golden age of tuners is history, but some great ones are readily available on the used market. A few you might consider are the McIntosh MR-78 or MR-80, Onkyo T-9090Mk.II, Tandberg TPT-3001, Accuphase T-100 or T-101, Pioneer TX-9800, TX-9500Mk.II, F-91, or F-93, Denon TU-800 or TU-850, Yamaha CT-7000, T-2, or T-85, Rotel RHT-10, Kenwood L-07TMk.II, HK Citation 23, Luxman 117, and JVC 1100. (Sorry, I can't remember exact model #'s of the last two.) Magnam Dynalab makes the best modern tuners, and many of their models are also readily available on the used market. I hope this information is helpful.
I don't want to completely contradict TWL's post, but those figures do not sound right to me at all. I think that what i've read relates to reception distances being limited to appr 15 degrees beyond the horizon. This is strictly discussing "ground wave" and not a signal that is "skipping" across the Ionosphere. Obviously, atmospheric conditions and local terrain will affect reception regardless of how good of an antenna you have or how high it is mounted.

Regardless of all of that, you would want to run the largest directional array that you can and get it up as high and out in the open as you can. A specialty antenna dedicated to FM reception rather than a combo TV / FM design should work noticeably better. For the record, John Dunlavy is the designer / engineer that holds the patent on the "log periodic" design that is so commonly used on many FM & TV antennas. John started out as an RF engineer and switched over to audio much later in his career. This could be why he has a slightly different approach to doing things as compared to most audio engineers.

Obviously, line loss at that long of a run is another consideration. While there is some very excellent low loss cable available for very reasonable cost ( Quad Shield RG-6 ), the impedance transformers ( adapters ) that are required to mate it to most antennas and many tuners can DRASTICALLY knock down the amount of signal that the tuner actually receives. From what i recall, most "generic" impedance transformers that are commercially available knock down your signal by appr 3 dB's. This means a reduction of signal of 50% if you have to run one of these at the antenna. If your tuner does not have a 75 ohm coaxial jack on it and you have to run another transformer there, you are only going to end up with appr 25% of the original signal. If you are going to run a splitter, count on even less.

With all of that in mind, running low loss foam twin-lead may be a better alternative. While twin-lead may be more susceptible to other forms of interference and is harder to install correctly for those very reasons ( you have to use "stand offs" to minimize impedance problems ), try looking at it this way: The stronger the on-band signal you have making it down to your tuner, the less noticeable any other forms of interence will be. That is, unless you have a consistent problem with high level interference on a regular basis.

I'll try and figure out the difference in loss between QS RG-6 and low loss twin-lead at FM broadcast frequencies. In the meantime, you better sit down and prepare yourself for how much a good antenna and adequate rotor will cost you. Sean
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Sean, the earth's circumference is approximately 24,900 miles at the equator. This is where you will get the longest arc. If you divide 24,900 miles by 360 degrees, you get 69.16666 miles per degree. This is at the equator(longest arc) and is less at other latitudes and angles(the earth not being truly spherical, and all) and excluding terrain obstacles. So, our best case is 69 miles for one degree of arc. This is the horizon. Depending on the height of the transmitting and receiving antennae, the direct distance may be somwhat increased. However, any way you slice it, the 120 mile distance(almost 2 degrees of arc) is at the very outer reaches of possiblity for reception. This is compounded by the fact that it is just far enough to also be right in the typical "skip zone" for ionosphere reflection, so it is neither close enough nor far away enough for direct or rebounded signals.