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The output power of a TV transmitter is the electric power applied to antenna system. There are two definitions: nominal (or peak) and thermal. Analogue television systems put about 70% to 90% of the transmitters power into the sync pulses. The remainder of the transmitter's power goes into transmitting the video's higher frequencies and the FM audio carrier. Digital television modulation systems are about 30% more efficient than analogue modulation systems overall. == Analogue vs digital == Analogue * The large amount of energy that Sync Pulses use is largely independent of the measurement system and efficiency of the analogue TV transmitter (as most analogue transmitters have on average 75% efficiency). * The transmission of FM audio (including Stereo subcarriers) is only overall the 3rd largest consumer of TV transmitter power. * Power consumption (most to least) : Sync Pulses, High Frequency Video, FM Audio, Vestigial AM Digital * DVB like transmission systems, with their groups of mathematically related carriers are not quite as energy efficient as 8VSB systems * 8VSB transmission systems only provide a limited "Forced DC" signal (that consumes about 7% of the transmitters energy) that under multipath conditions can be lost causing a signal lock loss event 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「Output power of an analog TV transmitter」の詳細全文を読む スポンサード リンク
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