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en:prinzip [2021/04/15 22:23]
mb
en:prinzip [2021/04/16 13:11] (aktuell)
mb
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 ==== Tuned Radio Frequency Receivers (TRF) ==== ==== Tuned Radio Frequency Receivers (TRF) ====
-{{:​images:​grundlagen-geradeausempfaenger.jpg?​direct&​400 |}}+{{:​images:​grundlagen-geradeausempfaenger.jpg?​direct&​400|}}
  
 In the **[[wp>​Tuned radio frequency receiver]]** (TRF), the radio frequency signal from the antenna is selected in a tuned circuit and fed directly to the demodulator. In some cases, the radio frequency is fed to a tuned amplifier stage before demodulation;​ in most cases, the audio frequency is amplified after demodulation to give more than just headphone reception. In the **[[wp>​Tuned radio frequency receiver]]** (TRF), the radio frequency signal from the antenna is selected in a tuned circuit and fed directly to the demodulator. In some cases, the radio frequency is fed to a tuned amplifier stage before demodulation;​ in most cases, the audio frequency is amplified after demodulation to give more than just headphone reception.
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 A typical intermediate frequency often used in domestic radios is 455 kHz. A typical intermediate frequency often used in domestic radios is 455 kHz.
  
-==== double-superhet ====+==== Double conversion ​superhet ====
 {{:​images:​grundlagen-doppelsuperhet.jpg?​direct&​400 |}} {{:​images:​grundlagen-doppelsuperhet.jpg?​direct&​400 |}}
 Since receiver developers when deciding about the intermediate frequency always have to find a compromise between the risk of mirror frequencies appearing (the appearance of a double of a strong signal as a "ghost station"​ in the wrong place on the dial should be prevented) and selectivity,​ the principle of the **double conversion superhet** or **double conversion** is used in high-quality receivers. Since receiver developers when deciding about the intermediate frequency always have to find a compromise between the risk of mirror frequencies appearing (the appearance of a double of a strong signal as a "ghost station"​ in the wrong place on the dial should be prevented) and selectivity,​ the principle of the **double conversion superhet** or **double conversion** is used in high-quality receivers.
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 ===== Documents ===== ===== Documents =====
-The textbooks of the Swiss Army signal troops, with which the basics can be learned in a step by step self-study approach, are an excellent study source, but they are available only in germ,​an ​(and french) language:+The textbooks of the Swiss Army signal troops, with which the basics can be learned in a step by step self-study approach, are an excellent study source, but they are available only in german ​(and french) language:
   * [[http://​armyradio.wiki/​lib/​exe/​fetch.php?​media=manuals:​techn-grundlagen-band-1-small.pdf | Technical Basics for Signal Mechanics, Volume 1]]   * [[http://​armyradio.wiki/​lib/​exe/​fetch.php?​media=manuals:​techn-grundlagen-band-1-small.pdf | Technical Basics for Signal Mechanics, Volume 1]]
   * [[http://​armyradio.wiki/​lib/​exe/​fetch.php?​media=manuals:​techn-grundlagen-band-2-small.pdf | Technical Basics for Signal Mechanics, Volume 2]]   * [[http://​armyradio.wiki/​lib/​exe/​fetch.php?​media=manuals:​techn-grundlagen-band-2-small.pdf | Technical Basics for Signal Mechanics, Volume 2]]
  
 ==== Additional information ==== ==== Additional information ====
en/prinzip.1618518186.txt.gz · Zuletzt geändert: 2021/04/15 22:23 von mb