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A linjesender (English: "line transmitter") was a low power longwave transmitter system used for broadcasting in Norway. It consisted of a power line communication system, which fed the radio programme on a frequency in the longwave broadcasting range into domestic powerlines. The last linjesender in Norway was closed in 1987 although the Swiss counterpart survived another ten years. ==Features== The typical powers used by linjesenders were between 250 watts and 2 kW. Most systems used frequencies in the longwave band or in between the LW and MW band although some used medium wave or frequencies below the standard LW band which required special receivers. Wired broadcasting had several advantages over conventional broadcasting: # Less susceptible to interference # Potentially greater number of programmes (as overcrowding on the frequency bands was less of a problem) # Potentially greater audio quality as wired transmissions were not subject to the same restrictions on bandwidth as terrestrial AM broadcasts. # In a mountainous country like Switzerland it was difficult to obtain satisfactory national coverage with conventional transmitters. Particularly in the 1930s when transmissions were typically less powerful than today. On the other hand there were practical and economic difficulties in extending such services to remote or thinly populated regions. Wired broadcasting could also be used by governments as a tool of censorship through promoting ownership of wire-only receivers which could not receive foreign stations. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Linjesender」の詳細全文を読む スポンサード リンク
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