|MadSci Network: Engineering|
It's just about impossible to predict how well one of these gadgets would work for you. It is true that your house wiring acts as an antenna; any piece of wire will. However, that does not mean that the house wiring is a GOOD antenna that provides a CLEAN signal. What the device does is pass any TV signals picked up by the wiring to your TV or VCR while blocking the household AC current. What the device will also do is pass along any interference ("static") carried on the wiring, as well. WARNING: Under no circumstances should anyone attempt to directly connect their household electric wiring to the antenna terminals of a TV or VCR. Damage to your wiring, damage to the equipment, a fire, electric shock, or even death are the likely outcomes. The problem is that the configuration of the wiring in your house is unlikely to be a good antenna. The lengths of the wires are not matched to the wavelengths of TV signals, and the directivity ("antenna pattern") is not controlled or controllable, and impedance of this "antenna" is poorly matched to free space. This meaning some stations may come in OK while others don't come in at all or are subject to a great deal of ghosting and fading, and there's nothing you can do about it. Also, any electric motors in your house (especially for small appliances), flourescent lights, and light dimmers are likely to generate interference that degrades the TV picture (streaks and "snow"). This electrical "noise" will is carried on the electric wiring and this device will pass it directly into your TV or VCR along with the desired signals. I've seen this things advertised, but for the same amount of money, I'd simply go buy a pair of rabbit ears (that's what I use). You can get fancier ones that include a signal amplifier, but a set in the $10-$20 range with a "channel selection" knob will work about as well as a set of rabbit ears can work, assuming they're connected to anything other than the very cheapest TV or VCR. This is because the amplifier in the tuner of even a moderate-quality TV or VCR is likely to be better (i.e., have lower noise figure) than the amplifier in a pair of rabbit ears. Steve Czarnecki P.S. #1 I'm assuming you don't live in a building with metal walls or a metal skeleton (much commercial construction and an increasing amount of residential construction uses galvanized steel studs rather than wooden 2-by-4 studs). If you do live in a building with a metal wall or metal studs, only an outdoor antenna is likely to work well. P.S. #2 An alternative to mounting an antenna outside is to mount it in indoors (in the attic, for example), assuming you don't have metal walls, a "tin" roof, or metal studs in the walls. In a wooden building, the antenna will work just fine indoors. They're usually mounted outdoors simply to get the highest possible vantage and becuase they take a lot of space.
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