From: owner-ammf-digest@smoe.org (alt.music.moxy-fruvous digest) To: ammf-digest@smoe.org Subject: alt.music.moxy-fruvous digest V14 #12177 Reply-To: ammf@fruvous.com Sender: owner-ammf-digest@smoe.org Errors-To: owner-ammf-digest@smoe.org Precedence: bulk alt.music.moxy-fruvous digest Sunday, September 10 2023 Volume 14 : Number 12177 Today's Subjects: ----------------- Improve Your Sleep by Avoiding This Mistake ["Pain Relief" Subject: Improve Your Sleep by Avoiding This Mistake Improve Your Sleep by Avoiding This Mistake http://acehardwaremakita.shop/JymIRXoKG_V7Sp8Bam8r7GQ3in5-d6DxwKCTWBia1tbgXVEQ3Q http://acehardwaremakita.shop/j8xB_Mw2poNlKQmG7_rZ3ZhcgLi9JyyiGyVVysrY2LF3gDNwZA Grote Reber was inspired by Jansky's work, and built a parabolic radio telescope 9m in diameter in his backyard in 1937. He began by repeating Jansky's observations, and then conducted the first sky survey in the radio frequencies. On February 27, 1942, James Stanley Hey, a British Army research officer, made the first detection of radio waves emitted by the Sun. Later that year George Clark Southworth, at Bell Labs like Jansky, also detected radiowaves from the Sun. Both researchers were bound by wartime security surrounding radar, so Reber, who was not, published his 1944 findings first. Several other people independently discovered solar radio waves, including E. Schott in Denmark and Elizabeth Alexander working on Norfolk Island. Chart on which Jocelyn Bell Burnell first recognised evidence of a pulsar, in 1967 (exhibited at Cambridge University Library) At Cambridge University, where ionospheric research had taken place during World War II, J. A. Ratcliffe along with other members of the Telecommunications Research Establishment that had carried out wartime research into radar, created a radiophysics group at the university where radio wave emissions from the Sun were observed and studied. This early research soon branched out into the observation of other celestial radio sources and interferometry techniques were pioneered to isolate the angular source of the detected emissions. Martin Ryle and Antony Hewish at the Cavendish Astrophysics Group developed the technique of Earth-rotation aperture synthesis. The radio astronomy group in Cambridge went on to found the Mullard Radio Astronomy Observatory near Cambridge in the 1950s. During the late 1960s and early 1970s, as computers (such as the Titan) became capable of handling the computationally intensive Fourier transform inversions required, they used aperture synthesis to create a 'One-Mile' and later a '5 km' effective aperture using the One-Mile and Ryle telescopes, respectively. They used the Cambridge Interferometer to map the radio sky, producing the Second (2C) and Third (3C) Cambridge Catalogues of Radio Sour ------------------------------ Date: Fri, 8 Sep 2023 12:03:02 +0200 From: "Kohls Unlocked" Subject: Celebrating Kohl's anniversary with an Le Creuset Celebrating Kohl's anniversary with an Le Creuset http://redboosttonic.life/tf_RdfJkoh4UBDuOryKJg8OyK-w9a2VkECPcRQ6DJ6_cc7slQw http://redboosttonic.life/UQqDUL2Faxrb9As-iXhU_A4q-ZacpB5_6ry3fEpwI4hYSqi2Mw wavelength in size, such as quarter-wave monopoles and half-wave dipoles, don't have much directivity (gain); they are omnidirectional antennas which radiate radio waves over a wide angle. To create a directional antenna (high gain antenna), which radiates radio waves in a narrow beam, two general techniques can be used. One technique is to use reflection by large metal surfaces such as parabolic reflectors or horns, or refraction by dielectric lenses to change the direction of the radio waves, to focus the radio waves from a single low gain antenna into a beam. This type is called an aperture antenna. A parabolic dish is an example of this type of antenna. A second technique is to use multiple antennas which are fed from the same transmitter or receiver; this is called an array antenna, or antenna array. If the currents are fed to the antennas with the proper phase, due to the phenomenon of interference the spherical waves from the individual antennas combine (superpose) in front of the array to create plane waves, a beam of radio waves traveling in a specific direction. In directions in which the waves from the individual antennas arrive in phase, the waves add together (constructive interference) to enhance the power radiated. In directions in which the individual waves arrive out of phase, with the peak of one wave coinciding with the valley of another, the waves cancel (destructive interference) reducing the power radiated in that direction. Similarly, when receiving, the oscillating currents receiv ------------------------------ End of alt.music.moxy-fruvous digest V14 #12177 ***********************************************