Edge-of-range Issues
Those at the edge of a station's broadcast range will typically notice static in an analog broadcast, while error correction will keep a digital signal clear until it hits the cliff effect and suddenly disappears completely. FM stations may flip back and forth (sometimes annoyingly rapidly when moving) due to the capture effect, while AM stations (including TV video) may overlay or fade with each other.
FM stereo will tend to get static more quickly than the monophonic sound due to its use of subcarriers, so stations may choose to extend the usable part of their range by disabling the stereo generator. Listeners can also choose to disable stereo decoding on the receiver, though loss of the stereo pilot tone causes this to happen automatically. Because this tends to turn on and off when at the threshold of reception, and the threshold is often set too low by the manufacturer's product design, manually disabling this when at the edge of the broadcast range prevents the annoying noisy-stereo/quiet-mono switching.
The same is true of analog TV stereo and second audio programs, and even for color TV, all of which use subcarriers. Radio reading services and other subcarrier services will also tend to suffer from dropouts sooner than the main station.
Technologies are available that allow for switching to a different signal carrying the same radio program when leaving the broadcast range of a station. Radio Data System allows for switching to a different FM or station with the same identifier, or even to (but not necessarily from) an AM station. Satellite radio also is designed to switch seamlessly between repeaters and/or satellite when moving outside the range of one or the other. HD Radio switches back to the analog signal as a fallback when the edge of the digital range is encountered, but the success of this from the listener's perspective depends on how well the station's broadcast engineer has synchronized the two.
Read more about this topic: Broadcast Range
Famous quotes containing the word issues:
“How to attain sufficient clarity of thought to meet the terrifying issues now facing us, before it is too late, is ... important. Of one thing I feel reasonably sure: we can’t stop to discuss whether the table has or hasn’t legs when the house is burning down over our heads. Nor do the classics per se seem to furnish the kind of education which fits people to cope with a fast-changing civilization.”
—Mary Barnett Gilson (1877–?)