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Maximizing FM sensitivity, 88-91
I live in the Blue Ridge Mountains of Virginia, within range of
FM stations in Washington, D.C., Richmond and Charlottesville. I can get reasonable reception, usually, of WPFW 89.3 and WCVE 88.9, if I try various permutations of my dipole antenna placement to fit the current atmospheric conditions or whatever it is. Reception of WTJU 91.1 is problematic, with usually at least a little static. I'm wondering if I can improve this with a better antenna and/or a better tuner. I read the great discussion in this newsgroup on this subject (see: http://groups-beta.google.com/group/...3d134af10c6a93). I am currently using an old Onkyo receiver (TX-36). I have an Adcom tuner/preamp GTP-400 and Adcom poweramp GFA-545 II, but I couldn't get as good reception and had to revert to my old Onkyo (which, though digital, lets me tune to 91.2 for example, a necessity to have a chance to bring in WTJU at 91.1 because of the bleed-over from the strong signal of WETA at 90.9). My two questions a 1. If I get one of the tuners mentioned in the thread above, does that mean I need to get a pre-amp (without a tuner) that will take the input from the tuner? I assume I cannot use a separate tuner with my two Adcom units. 2. If I get a directional antenna like the Winegard HD6065, will it only be of use for one of my three target stations, depending on how it is aligned? Might I do better with the FM-2G-C FM vertical dipole antenna (the so-called college band antenna) that is specifically designed to bring in stations in my target range, according to the info at the fanfare site (www.fanfare.com)? It may be obvious from this post that I am not the true high-end audiophile. My primary concern is FM reception sensitivity, in the specific range of 88.5 to 91.1. I see that if I am willing to spend $400 or more I can get a used McIntosh MR-77 tuner from ebay; could that really make a difference in the static that usually accompanies my reception of WTJU? These are three great radio stations, by the way. Thanks for the help! -David Cox Syria, Virginia |
#3
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David Hamilton Cox wrote:
I live in the Blue Ridge Mountains of Virginia, within range of FM stations in Washington, D.C., Richmond and Charlottesville. I can get reasonable reception, usually, of WPFW 89.3 and WCVE 88.9, if I try various permutations of my dipole antenna placement to fit the current atmospheric conditions or whatever it is. Reception of WTJU 91.1 is problematic, with usually at least a little static. I'm wondering if I can improve this with a better antenna and/or a better tuner. You'll always get much more improvement by putting money into your antenna setup. Your big problem is that you're using a di-pole, which is damn near useless. I strongly urge you to invest in a good roof-mounted antenna, a sturdy mast system and a good antenna rotor. All told, you could put together a top notch system for well under $300. The following is a site chock full of information. http://pages.cthome.net/fmdx/mailroom.html The Winegard HD6065 is a very good antenna. By using a rotor, you'll be able to orient it for any station you wish. There are better antennas than the Winegard, and cost proportionally more. But it's like the difference between a Toyota Camry, a good reliable and comfortable car, and a Lexus, which has the same frame and drive train as a Camry, but more creature comforts. Think of your di-pole antenna as a skateboard with one wheel missing. Places to buy everything you need: http://www.starkelectronic.com/ http://www.warrenelectronics.com/ Save money and build your own antenna! http://pages.cthome.net/fmdx/FincoFM.html http://www.siber-sonic.com/FM_reception/rooftop.html http://www.ifwtech.co.uk/g3sek/diy-yagi/index.htm If you put a great tuner on a di-pole antenna, it's like trying to get NFL football players to perform on a diet of rice cakes and water. A better tuner will work better of course. But either your Adcom or Onkyo on a Winegard, with a rotor, would far outperform any McIntosh tuner, a Marantz 10B, Sequerra, or whatever being connected to a di-pole, or even one of the cheap omni-directional antennas you mention. Good luck! Russ |
#4
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David Hamilton Cox writes:
I live in the Blue Ridge Mountains of Virginia, within range of FM stations in Washington, D.C., Richmond and Charlottesville. I can get reasonable reception, usually, of WPFW 89.3 and WCVE 88.9, if I try various permutations of my dipole antenna placement to fit the current atmospheric conditions or whatever it is. Reception of WTJU 91.1 is problematic, with usually at least a little static. I'm wondering if I can improve this with a better antenna and/or a better tuner. I read the great discussion in this newsgroup on this subject (see: http://groups-beta.google.com/group/...3d134af10c6a93). I am currently using an old Onkyo receiver (TX-36). I have an Adcom tuner/preamp GTP-400 and Adcom poweramp GFA-545 II, but I couldn't get as good reception and had to revert to my old Onkyo (which, though digital, lets me tune to 91.2 for example, a necessity to have a chance to bring in WTJU at 91.1 because of the bleed-over from the strong signal of WETA at 90.9). My two questions a 1. If I get one of the tuners mentioned in the thread above, does that mean I need to get a pre-amp (without a tuner) that will take the input from the tuner? I assume I cannot use a separate tuner with my two Adcom units. It ought to be possible to do that. Most receivers have a spare input. 2. If I get a directional antenna like the Winegard HD6065, will it only be of use for one of my three target stations, depending on how it is aligned? Might I do better with the FM-2G-C FM vertical dipole antenna (the so-called college band antenna) that is specifically designed to bring in stations in my target range, according to the info at the fanfare site (www.fanfare.com)? You might, yes. It may be obvious from this post that I am not the true high-end audiophile. My primary concern is FM reception sensitivity, in the specific range of 88.5 to 91.1. I see that if I am willing to spend $400 or more I can get a used McIntosh MR-77 tuner from ebay; could that really make a difference in the static that usually accompanies my reception of WTJU? The best advice for radio reception is always to fix the antenna first, and only then to worry about the tuner. Firstly, you don't say where your antenna is. Generally speaking, high is good. If your antenna is not on the roof of the building in which you live, make it so. You might be able to solve the problem simply by mounting your antenna on a longer pole. Generally speaking, directional is better than omnidirectional. But as you perhaps know, an antenna that boosts stations from one direction cancels stations from other directions. You might need a rotator. So, here's what you should do: 1. Move your antenna higher. 2. Try a good quality omni or try a directional antenna and only after you've tried all of these 4. Get another receiver. Andrew. |
#5
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I live in the Blue Ridge Mountains of Virginia, within range of
FM stations in Washington, D.C., Richmond and Charlottesville. I can get reasonable reception, usually, of WPFW 89.3 and WCVE 88.9, My suggestion is to try hooking up the vable TV if you have it, to the receiver with a 300-75 ohm adaptor. Most older analog systems carry FM channels as part of the service. |
#6
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Isaac Wingfield asked how far I am from the stations
in question. About 70+ miles from D.C. and Richmond, and 35-40 from Charlottesville. So I suppose I should be grateful for what reception I can get, and have a realistic attitude to living with atmospheric variances. I tried several different models of indoor Terk antennae, which did not work as well as the folded wire dipole. I think I will try a Winegard or some similar outdoor antenna. My brother, an electrician, suggested I consider mounting the antenna on a nearby tree to eliminate the risk from lightning. That seems far-fetched to me, considering how far the trees bend over when the wind blows hard. I asked if proper grounding wouldn't solve the problem with lightning, and I think he said it would. My officemate at work brought a XM satellite receiver/boombox in, so I have had a good chance to evaluate it. It's not bad, but it cannot compare to an authentic local station with a distinctive flavor. There's no real soul in XM, for my money. YMMV. -David Cox |
#7
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Hi David,
You can get much improved reception with a good, directional FM/VHF antenna. You can mast mount it on the side of your house or use the chimney, etc, where ever you get the best line of sight shot at the transmitters. Since you are getting some reception on your dipole, you should be able to get a much stronger signal and better selectivity to reduce interference from the neighboring station with the directional unit. You will probably need to get a rotator also to get all of the stations equally well, but sometimes you get lucky and find that they are near enough to get decent reception of all or at least optimise one and get acceptable reception from the others. each situation is unique there. Grounding is done with a solid, heavy wire from the antenna mast straight into the earth via a rod at the base of the installation to create the shortest and lowest resistance path to ground. No need to worry about climbing trees! The nice thing about using an antenna is that it is a one time installation and one time expense. After that, programming is free. Any indoor antenna, amplified or not will be futile. You could try mounting the dipole in your attic to get it much higher, but that can change the signal due to reflections, so it works sometimes better than others. If you do or if you run an roof-top directional, then you will need to use 75 ohm coax as a lead. You can amplifier a directional antenna if needed at the antenna, but the dipole will just have the noise that you already hear amplified by using one in the home. As you have found, the "terk variety" are pretty much useless. -Bill www.uptownaudio.com Roanoke VA (540) 343-1250 "David Hamilton Cox" wrote in message ... Isaac Wingfield asked how far I am from the stations in question. About 70+ miles from D.C. and Richmond, and 35-40 from Charlottesville. So I suppose I should be grateful for what reception I can get, and have a realistic attitude to living with atmospheric variances. I tried several different models of indoor Terk antennae, which did not work as well as the folded wire dipole. I think I will try a Winegard or some similar outdoor antenna. My brother, an electrician, suggested I consider mounting the antenna on a nearby tree to eliminate the risk from lightning. That seems far-fetched to me, considering how far the trees bend over when the wind blows hard. I asked if proper grounding wouldn't solve the problem with lightning, and I think he said it would. My officemate at work brought a XM satellite receiver/boombox in, so I have had a good chance to evaluate it. It's not bad, but it cannot compare to an authentic local station with a distinctive flavor. There's no real soul in XM, for my money. YMMV. -David Cox |
#8
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David Hamilton Cox wrote:
I live in the Blue Ridge Mountains of Virginia, within range of FM stations in Washington, D.C., Richmond and Charlottesville. I can get reasonable reception, usually, of WPFW 89.3 and WCVE 88.9, if I try various permutations of my dipole antenna placement to fit the current atmospheric conditions or whatever it is. Reception of WTJU 91.1 is problematic, with usually at least a little static. I'm wondering if I can improve this with a better antenna and/or a better tuner. I read the great discussion in this newsgroup on this subject (see: snip -David Cox Syria, Virginia The answer is a yagi antenna. Most "TV" antennas will work just fine, since the FM band is inbetween channels 5 and 6, iirc. Depending on your distance from the stations in question, you want an antenna that would give you at least good quality reception from TV stations radiating from the same area. Keep in mind that many FM stations are *lower* power than the typical city based VHF TV station, so you may need a bigger antenna = more gain. A preamp on the pole with the antenna is fine, assuming you have a signal to amplify. FM works on a principle called "capture ratio" (iirc) which briefly stated means that if you get enough signal above a threshold it is quiet and clean. Use a good quality 100% shield coax down from the antenna. The higher up the antenna is, the better. The higher above surrounding solid surfaces (roofs etc...) the better. Ground the antenna (mast) to a good outside ground for lightning protection. Use stainless hardware if you expect it to be around for more than 5-8 years... There's also goo used by the cable and phone people (and sold in electrical supply houses) that is sticky and like a sort of putty/tape that works wonders for water/weather proofing of connectors and other electrical junctions on an antenna. The LONGER and bigger the antenna, the greater the number of elements, the more gain it will have... You can of course build a purpose build homebrew yagi antenna just for the freqs of interest which will be smaller and have fewer elements, and maybe more gain in the FM band... check the ARRL antenna handbook for that data or any Amateur Radio Handbook for general antenna building ideas... or your local ham radio club. :- ) (it will last longer too...) Any yagi will have a good "front to back ratio" meaning it has gain off the front, and a null off the back, but the sides are pretty much "0" gain, about the same as a little vertical would be, so you should have no problem with the much stronger local stations, unless there happen to be fairly high power stations in the direction you are pointing, and the ones locally off the back are not very strong in the first place... but that is what an antenna switch is for - to go from ant A to ant B - your local dipole to the yagi. Unless merely getting up in the air will do the trick, then a silly vertical is pointless. You can test the idea by going up on the roof with a portable FM or to a nearby hill with the car... that should give you an inkling if the stations you want will come in with just adding some height to your antenna... Oh, if the stations of interest do NOT come in with merely height being added to the antenna, and they are NOT all in the same direction, you will need either multiple antennas fixed at the locations or an antenna rotator. _-_-bear |
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