DTV signals need to get better or antenna's cheaper. For many it too technical to hook anything up , even a VCR. Maybe this will be godd, all over the air sets going fuzzy in June, maybe they'll get out enjoy life and spend some money and save the economy Hussein Obama is ruining.
Effects of poor reception
Changes in signal reception from factors such as degrading antenna connections or changing weather conditions may gradually reduce the quality of analog TV. The nature of digital TV results in a perfect picture initially, until the receiving equipment starts picking up noise or losing signal. Some equipment will show a picture even with significant damage, while other devices may go directly from perfect to no picture at all (and thus not show even a slightly damaged picture). This latter effect is known as the digital cliff or cliff effect.
For remote locations, distant channels that as analog signals were previously usable in a snowy and degraded state may as digital signals be perfect or may become completely unavailable. In areas where transmitting antennas are located on mountains, viewers who are too close to the transmitter may find reception difficult or impossible because the strongest part of the broadcast signal passes above them. The use of higher frequencies will add to these problems, especially in cases where a clear line-of-sight from the receiving antenna to the transmitter is not available. Many intermittent signal fading conditions, such as the rapid-fade effect caused by reflections of UHF television signals from passing aircraft, will not produce intermittently-snowy video, but potential intermittent loss of the entire signal, which most receivers will display as a frozen ("paused") image or a black screen for the duration of the signal loss.
Multi-path interference is a much more significant problem for DTV than for analog TV and affects reception, particularly when using simple antennas such as rabbit ears. This is perceived as "ghosting" in the analog domain, but this same problem manifests itself in a much more insidious way with DTV. (What was "ghosting" in analog becomes intersymbol interference (ISI), which causes data corruption, in digital TV. Beyond a certain point, corrupt data is as good as no data.) IEEE engineers recommend using an attic or outdoor antenna for DTV, if possible, rather than an indoor antenna, because reflections and other interactions of the signal with objects (including bodies) in the room will increase multipath interference. Unlike the problems of the preceding paragraph, multi-path can be worse for DTV under high signal conditions. It is perceived by the viewer as a spotty loss of audio or picture freezing and pixelation as people move about in the vicinity of the antenna and is often worse in wet weather due to increased reflection or re-polarization of the DTV signal arriving from multiple paths. In extreme cases the signal is lost completely. The cure is to employ a directional antenna outdoors, aligned with the transmitting location.
Dynamic multipath interference, in which the delay and magnitude of reflections are rapidly changing, is particularly problematic for digital reception. While this just produces moving and changing ghost images for analog TV, it can render a digital signal impossible to decode. The 8VSB-based standards in use in North American ATSC broadcasts are particularly vulnerable to problems from dynamic multipath; this has the potential to severely limit mobile or portable use of digital television receivers. Solving the problem might require that different standards be adopted for mobile use.
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