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Triple-conversion (superhet)
A superheterodyne receiver, often shortened to superhet, is a type of radio receiver that uses frequency mixer, frequency mixing to convert a received signal to a fixed intermediate frequency (IF) which can be more conveniently processed than the original carrier frequency. It was long believed to have been invented by US engineer Edwin Armstrong, but after some controversy the earliest patent for the invention is now credited to French radio engineer and radio manufacturer Lucien Lévy. Virtually all modern radio receivers use the superheterodyne principle; except those Software-defined_radio, software-defined radios using ''direct sampling''. History Heterodyne Early Morse code radio broadcasts were produced using an alternator connected to a spark gap transmitter, spark gap. The output signal was at a carrier frequency defined by the physical construction of the gap, modulated by the alternating current signal from the alternator. Since the output frequency of the alternator ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toshiba Vacuum Tube Radio
, commonly known as Toshiba and stylized as TOSHIBA, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. Its diversified products and services include power, industrial and social infrastructure systems, elevators and escalators, electronic components, semiconductors, hard disk drives (HDD), printers, batteries, lighting, as well as IT solutions such as quantum cryptography which has been in development at Cambridge Research Laboratory, Toshiba Europe, located in the United Kingdom, now being commercialised. It was one of the biggest manufacturers of personal computers, consumer electronics, home appliances, and medical equipment. As a semiconductor company and the inventor of flash memory, Toshiba had been one of the top 10 in the chip industry until its flash memory unit was spun off as Toshiba Memory, later Kioxia, in the late 2010s. The Toshiba name is derived from its former name, Tokyo Shibaura Denki K.K. (Tokyo Shibaura Electric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
