File:Microwave_Apparatus_-_Jagadish_Chandra_Bose_Museum_-_Bose_Institute_-_Kolkata_2011-07-26_4051.JPG
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Summary
DescriptionMicrowave Apparatus - Jagadish Chandra Bose Museum - Bose Institute - Kolkata 2011-07-26 4051.JPG |
English: Microwave transmitter and receiver used by Sir Jagadish Chandra Bose (also written Jagadis Chunder Bose) (30 November, 1858 – 23 November, 1937), in his pioneering experiments with microwaves around 1897. The spark gap transmitter (right) used a spark gap radiator made of three tiny 3 mm metal balls excited by high voltage from an induction coil to generate microwaves at 60 GHz. The transmitter was enclosed inside the metal box (right) to prevent sparks from the coil's interrupter from disturbing the action of the receiver, and the microwaves emanated from the waveguide (metal tube). The receiver (left) used a galena point contact crystal rectifier inside the horn antenna and a galvanometer to detect the waves. The galvanometer (left) and battery (right) are modern replacements for Bose's original apparatus.
Bose was the first to invent the crystal detector, horn antenna, dielectric lens, and other components now used in microwave apparatus. Jagadish Chandra Bose museum which is the part of the Bose Institute, Kolkata, is displaying some of the instruments designed, made and used by Sir J. C. Bose with his personal belongings, memorabilia and an exhibition on his Life and Works. Français : Appareil émetteur et détecteur de micro-ondes (60 GHz) de Bose (au Bose Institute à Kolkata, en Inde). Le récepteur (à gauche) utilisait un détecteur de cristaux de galène, positionné dans une w:fr:antenne:antenne cornet et un galvanomètre pour détecter les micro-ondes. Bose a inventé le détecteur radio à cristal, le guide d'ondes, l'antenne cornet et d'autres appareils utilisés aux fréquences de la gamme des micro-ondes. |
Date | |
Source | Own work |
Author | Biswarup Ganguly |
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Annotations InfoField | This image is annotated: View the annotations at Commons |
Galena point-contact detector inside horn antenna
Galvanometer to detect current from detector (modern replacement)
Spark-gap transmitter generated microwaves by electric sparks between tiny metal balls inside metal box. The microwaves emerged from the waveguide aperture (left). The high voltage which produced the sparks was generated by an induction coil (not shown)
Stand to support prisms or other materials to be irradiated by the microwaves
Items portrayed in this file
depicts
some value
26 July 2011
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current | 04:51, 9 March 2012 | 4,288 × 2,848 (5.76 MB) | Gangulybiswarup |
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Date and time of data generation | 16:06, 26 July 2011 |
Lens focal length | 28 mm |
User comments | Biswarup Ganguly |
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File change date and time | 12:39, 7 March 2012 |
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Date and time of digitizing | 16:06, 26 July 2011 |
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