File:Spark gap transmitter bandwidth - A.png
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Summary
[edit]DescriptionSpark gap transmitter bandwidth - A.png |
English: "Characteristic of a commercial transmitter on shipboard showing broad range of waves sent out." A graph showing the broad band of frequencies radiated by a spark gap transmitter, the type of radio transmitter used until about 1920. The vertical axis is the energy of the received signal at the test receiver, and the horizontal axis is wavelength. Since they generated radio waves using an impulsive spark, spark transmitters did not transmit on a single frequency but a band of frequencies, and tended to interfere with other transmitters on neighboring frequencies. From the graph, this transmitter's center wavelength was 800 meters (a frequency of 370 kHz) but it blanketed the band between 500 and 1200 meters (600 - 250 kHz) with its signal. |
Date | |
Source | Edelman, Philip E.; Frederick A. Kolster, graphs (1914) Experimental Wireless Stations, Minneapolis, MN, pp. 61–65 ISBN: 978-1362557616. |
Author | Frederick A. Kolster |
Licensing
[edit]Public domainPublic domainfalsefalse |
This work is in the public domain in its country of origin and other countries and areas where the copyright term is the author's life plus 70 years or fewer. This work is in the public domain in the United States because it was published (or registered with the U.S. Copyright Office) before January 1, 1929. | |
This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights. |
https://creativecommons.org/publicdomain/mark/1.0/PDMCreative Commons Public Domain Mark 1.0falsefalse
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current | 19:36, 3 February 2023 | 722 × 863 (135 KB) | Mu301 (talk | contribs) | Uploaded a work by Frederick A. Kolster from {{cite book |last=Edelman |first=Philip E. |others=Frederick A. Kolster, graphs |date=1914 |title=Experimental Wireless Stations |url=https://books.google.com/books?id=0BpDAAAAIAAJ |location=Minneapolis, MN |publisher= |pages=61–65 |isbn=978-1362557616}} with UploadWizard |
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Horizontal resolution | 118.11 dpc |
Vertical resolution | 118.11 dpc |
File change date and time | 18:50, 3 February 2023 |