The first was the reinstatement of the ultrahigh-frequency discount, an arcane rule that digital technology had rendered obsolete.
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To test how it would fare when surrounded by magnetic fields, the team brought the seismometer to the ultrahigh-frequency antenna at the Toulouse Space Center to barrage it with transmitting and receiving radio signals.
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Last year, Free Press sued the agency over its decision to reinstate the UHF discount, which makes ultrahigh frequency television stations count as half of a normal station when calculating for whether a broadcaster is in compliance with the national media ownership cap.
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LES-1, also known as Lincoln Experimental Satellite 1, was a communications satellite launched by the United States Air Force on February 11, 1965 to study the use of UHF (ultrahigh-frequency) radio transmissions. It never achieved optimal orbit and was out of contact for more than 40 years before spontaneously resuming transmissions in 2012.
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Double-balanced mixers are very widely used in microwave communications, satellite communications, ultrahigh frequency (UHF) communications transmitters, radio receivers, and radar systems. Gilbert cell mixers are an arrangement of transistors that multiplies the two signals. Switching mixers use arrays of field-effect transistors or vacuum tubes. These are used as electronic switches, to alternate the signal direction.
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Lincoln Experimental Satellite 2, also known as LES-2, was a communications satellite, the second of nine in the Lincoln Experimental Satellite. Launched by the United States Air Force (USAF) on 6 May 1965, it demonstrated many then-advanced technologies including active use of the military's UHF (ultrahigh-frequency) band (225 to 400 MHz) to service hundreds of users.
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Dönitz revived Hermann Bauer's idea of grouping several submarines together into a Rudeltaktik ("pack tactic", commonly called "wolfpack") to overwhelm a merchant convoy's escorts. Implementation of wolfpacks had been difficult in World War I owing to the limitations of available radios. In the interwar years, Germany had developed ultrahigh frequency transmitters, while the Enigma cipher machine was believed to have made communications secure.
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MIL-STD-6011 exchanges digital information among airborne, land-based, and shipboard tactical data systems. It is the primary means to exchange data such as radar tracking information beyond line of sight. TADIL-A can be used on either high frequency (HF) or ultrahigh frequency (UHF). However, the U.S. Army uses only HF. Link 11 relies on a single platform to report positional information on sensor detections.
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This effect is widely used in research, and physics education as a simple experiment to demonstrate the reality of magnetic domains. In 1920, he invented the Barkhausen-Kurz oscillator, with K. Kurz, the first vacuum tube electronic oscillator to use electron transit-time effects. It was the first vacuum tube oscillator that could operate at ultrahigh frequency, up to 300 MHz, and inspired later microwave transit-time tubes such as the klystron. In 1921 he derived the first mathematical conditions for oscillation in electrical circuits, now called the Barkhausen stability criterion.
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The RFID Journal responded to this study not negating it rather explaining real-case solution: "The Purdue study showed no effect when ultrahigh-frequency (UHF) systems were kept at a reasonable distance from medical equipment. So placing readers in utility rooms, near elevators and above doors between hospital wings or departments to track assets is not a problem". However the case of ”keeping at a reasonable distance” might be still an open question for the RTLS technology adopters and providers in medical facilities. In many applications it is very difficult and at the same time important to make a proper choice among various communication technologies (e.g.
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Concurrent with their development, Lincoln also developed the Lincoln Experimental Terminals (LET), ground stations that used interference-resistant signaling techniques that allowed use of communications satellites by up to hundreds of users at a time, mobile or stationary, without involving elaborate systems for synchronization and centralized control. The 1st, 2nd, and 4th satellites in the LES series were designated "X-Band satellites," designed to conduct experiments in the "X-band", the military's UHF (ultrahigh-frequency) band (225 to 400 MHz) because solid-state equipment allowed for comparatively high output in this band, and also because the band had been previously used by West Ford.
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Concurrent with their development, Lincoln also developed the Lincoln Experimental Terminals (LET), ground stations that used interference-resistant signaling techniques that allowed use of communications satellites by up to hundreds of users at a time, mobile or stationary, without involving elaborate systems for synchronization and centralized control. The 1st, 2nd, and 4th satellites in the LES series were designated "X-Band satellites," designed to conduct experiments in the "X-band", the military's UHF (ultrahigh-frequency) band (225 to 400 MHz) because solid-state equipment allowed for comparatively high output in this band, and also because the band had been previously used by West Ford. LES-1, launched 11 February 1965, failed to depart from its original circular medium orbit when its onboard thruster failed to fire. The resultant tumbling and the improper orbit rendered the satellite useless for experimentation purposes.
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