88 Sentences With "medium frequency" | Random Sentence Generator

U-Gym uses medium-frequency electrotherapy to stimulate your muscles, nerves and meridians.

Listen to "Slow Steps" here alongside Locher's other recent solo single "Medium Frequency."

Sky and other broadly similar low frequency areas, skin tones in the medium frequency zone and high frequency items like clothing, foilage etc.

At the time, it revealed to Mashable that 10 percent of Uber trips in Sydney start or end within 200 metres (656 feet) of a medium frequency public transport hub.

Up till now, mobile communications have exclusively used low- and medium-frequency airwaves that can travel relatively long distances and can penetrate into buildings, while mmW bands have faced propagation challenges.

For medium frequency, less contrast is needed than for high or low frequency to detect the sinusoidal fluctuation.

In the U.S., license-free operation is also allowed on the medium frequency band, also known as the AM Broadcast Band. Similar to LowFER, MedFER is medium-frequency experimental radio. MedFER enthusiasts operate under FCC Part 15 rules using 0.1 W (a tenth of a watt) and a three-meter-long antenna between 510 kHz and 1705 kHz, coinciding with the U.S. AM radio band.

Medium frequency is defined as 5–15 kHz. Another style of division considers low frequency to be under 1 kHz, and medium frequency at between 1–10 kHz. American World War II era sonars operated at a relatively high frequency of 20–30 kHz, to achieve directionality with reasonably small transducers, with typical maximum operational range of 2500 yd. Postwar sonars used lower frequencies to achieve longer range; e.g. SQS-4 operated at 10 kHz with range up to 5000 yd.

A broadcasting transmitter at Lanner Hill (, ). It transmits mediumwave radio signals. It was built in 1942 by German POWs. It is sometimes referred to as Redruth MF, short for Redruth Medium Frequency (Medium Wave).

Based on 1881 Census records, the name Cree was of Medium Frequency in ten British counties, of which nine are in Scotland, headed by Ayrshire and Perthshire. Dunbartonshire is next and Nottinghamshire (the only English county in the top ten) fourth. Census data for Ireland is not available but we know that most Irish Cree families live in County Down. Data for the USA suggests that the surname Cree gained Medium Frequency in Pennsylvania by 1850, to which Iowa and New York could be added in 1880.

The ventrum is pale pink, with dark red throat. The male advertisement call is slow series of dull, medium-frequency notes, which to the human ear resemble the sound produced by striking together two pieces of wood.

However, several countries had already allocated the WRC-12 band to amateurs domestically. Previously, several other countries authorized temporary allocations or experimental operations on nearby frequencies. The band is in the Medium Frequency (MF) region, within the 415–526.5 kHz maritime band.

Medium frequency band, one or two High frequency bands - depends on model. A concentrated selection filter or piezofilter is used. Audio power amplifier is made on four or five transistors. Radio receivers have monaural headphone jacks and the speaker is automatically muted.

Developed from earlier Visual Aural Radio Range (VAR) systems, the VOR was designed to provide 360 courses to and from the station, selectable by the pilot. Early vacuum tube transmitters with mechanically rotated antennas were widely installed in the 1950s, and began to be replaced with fully solid-state units in the early 1960s. They became the major radio navigation system in the 1960s, when they took over from the older radio beacon and four-course (low/medium frequency range) system. Some of the older range stations survived, with the four-course directional features removed, as non-directional low or medium frequency radiobeacons (NDBs).

A "Z" marker was sometimes located at low- or medium-frequency range sites to accurately denote station passage. As airway beacons used the same 3,000 Hz audio frequency as the inner marker, the "A" indicator on older receivers can be used to detect the inner marker.

NARBA's provisions were largely supplanted in 1983, with the adoption of the Regional Agreement for the Medium Frequency Broadcasting Service in Region 2 (Rio Agreement), which covered the entire Western hemisphere. However, current AM band assignments in North America largely reflect the standards first established by the NARBA agreements.

This led him to formulate the mere-exposure hypothesis: the more you see something, the more you like it. Nuttin's original study showed that mere exposure can not be the cause of the name-letter effect, as letters with equal frequency were evaluated differently by people who had the letter in their names and those who did not. He also found that whereas the letter B is of low frequency in French and the letter Q of medium frequency, in experiments with French speakers the B was among the most highly liked letters and the Q was among the least liked. Similarly, in Polish the Y is a medium frequency letter, yet was still among the least preferred letters.

Cree is a surname which has several separate origins in England, Scotland and Ireland. It occurs in all those countries today and also in Australia, Canada, New Zealand and the United States. It is of Medium Frequency in Scotland and Northern Ireland (using the benchmarks of the Guild of One-Name Studies)(Spathaky 1998).

Department of National Defence Radio aeronautical navigation aids (navaids) use other frequencies. Non-directional beacons (NDB)s operate on low frequency and medium frequency bands 190–415 kHz and 510–535 kHz. The instrument landing system (ILS) glide path operates in the UHF range of 329.3–335.0 MHz with marker beacons at 75 MHz.

A medium frequency (MF) transmitter was installed in 1948. The public electricity network replaced the generators in 1980 and the headlamp was automated in 1989, as was a new sound signal. At an altitude of 168 metres above sea level, the lighthouse now has a range of 26 nautical miles. The bulbs emit a white flash every four seconds.

The HSK list of 8,848 high and medium frequency words in the People's Republic of China, and the Republic of China (Taiwan)'s TOP list of about 8,600 common traditional Chinese words are two other lists displaying common Chinese words and characters. Following the SUBTLEX movement, recently made a rich study of Chinese word and character frequencies.

270x270px The first model of the series, designed by Mykola Lebid in 1977. The radio has a reliable, user-friendly design and was popular in the USSR. Today receivers are still used by some owners, more than 40 years after the start of production. High frequency band ("KB") 30.6-31.8m, Medium frequency band ("СВ") 186.7-571.4m.

As negotiations were taking place the deal fell through leaving Osbourne's and Hadfield's to merge, with the foundry being located on Hadfield's East Hecla (Vulcan Road) site, and Edgar Allen's to purchase Jessop's, relocating Jessop's special alloy (medium frequency) melting on Edgar's Sheffield Road site and the 3-ton electric furnace at their Imperial Steel Works site.

As negotiations were taking place the deal fell through leaving Osborn's and Hadfield's to merge, with the foundry being located on Hadfield's East Hecla (Vulcan Road) site, and Edgar Allen's to purchase Jessop's, relocating Jessop's special alloy (medium frequency) melting on Edgar's Sheffield Road site and the 3-ton electric furnace at one end of the Tropenas Melting Shop.

The Long Range Certificate is an internationally valid certificate issued to radio station operators. It entitles the holder to participate in marine communications on leisure crafts using Marine VHF, Medium Frequency, High Frequency radios and Inmarsat satellite communication as agreed in Global Maritime Distress and Safety System. The certificate is consistent with the agreement of the Article S47 of the ITU Radio Regulations.

Olimpik-401 Mykola Lebid's original design is practically unchanged, minor variations in the strap fastening, black or silver color of the range switch and antenna attachment, etc. The radio has a reliable, user-friendly design and was popular in the USSR. Today receivers are still used by some owners. High frequency band ("KB") 30.6-31.8m, Medium frequency band ("СВ") 186.7-571.4m.

206x206px Redesigned, two HF bands instead of one. High frequency band 1 ("KB1") 40.5-50.8m, High frequency band 2 ("KB2") 24.8-31.7m, Medium frequency band ("СВ") 186.7-571.4m. Radio receiver was produced in two versions, with audio power amplifier on four or five transistors. The second version of the audio power amplifier uses an additional КТ315Б transistor to stabilize the output stage mode .

The electromagnetic spectrum has rigid definitions for "super low frequency", "extremely low frequency", "low frequency" and "medium frequency". Acoustics does not have a similar standard. The terms "low" and "mid" have roughly-defined historical meanings in sonar, because not many frequencies have been used over the decades. However, as more experimental sonars have been introduced, the terms have become muddled.

MF's position in the electromagnetic spectrum. Medium frequency (MF) is the ITU designation for radio frequencies (RF) in the range of 300 kilohertz (kHz) to 3 megahertz (MHz). Part of this band is the medium wave (MW) AM broadcast band. The MF band is also known as the hectometer band as the wavelengths range from ten to one hectometer (1000 to 100 m).

The DSC is a synchronous system using characters composed from a ten-bit error detecting code. The bits are encoded using frequency shift keying. For High Frequency and Medium Frequency two tones 170 Hz apart either side of the allocated frequency with 100 Baud symbol rate are used. For VHF the two tones used are 1300 and 2100 Hz with a symbol rate of 1200 Baud.

Typical mast radiator of a commercial medium wave AM broadcasting station, Chapel Hill, North Carolina, U.S. Medium wave (MW) is the part of the medium frequency (MF) radio band used mainly for AM radio broadcasting. The spectrum provides about 120 channels with limited sound quality. During daytime, only local stations can be received. Propagation in the night allows strong signals within a range of about 2,000 km.

Layers of the ionosphere. The Kennelly–Heaviside layer is the E region The Heaviside layer, sometimes called the Kennelly–Heaviside layer, named after Arthur E. Kennelly and Oliver Heaviside, is a layer of ionised gas occurring between roughly 90 and 150 km (56 and 93 mi) above the ground -- one of several layers in the Earth's ionosphere. It is also known as the E region. It reflects medium-frequency radio waves.

The source of light is of 400 W Metal Hallide Lamp while the rotation of optic is provided by electronic pulse motors. The lighthouse was fitted in 1983 with a medium frequency Radio beacon with a range of and has a call sign 'NY'. In 1985 a Racon was also fixed at the top of the lighthouse. The tower has a winding staircase access to the top consisting of 216 steps inside.

Nautel logo Nautel Ltd. is a Canadian manufacturer of AM and FM radio broadcast transmitters, navigational radio beacons, Differential Global Positioning System (DGPS) transmitters, NOAA weather radio transmitters, LF PNT/eLORAN transmitters, SONAR high-power low-frequency amplifiers and SONAR systems, medium frequency (MF) telegraph and NAVTEX transmitters, and high frequency (HF) amplifiers for dielectric heating applications. Nautel is best known as the first company to develop a commercially available fully solid state broadcast transmitter.

The vessels feature a Bharat RAWS-03 S-band radar using a DA08 antenna for air/surface search. The air search radar is a Bharat/Signaal RAWL-02 (PLN 517) D-band radar using a LW08 antenna. They use a One Decca Bridgemaster, BEL Rashmi (PIN 524) I-band radar with a ZW06 antenna for navigation. The ships are provided with a Bharat HUMSA (Hull Mounted Sonar Array), a medium-frequency, active panoramic search and attack sonar.

Bremen Castings foundry produces castings made from recycled materials such as plate and structural steel and old cast products. A Cupola and medium frequency furnaces are used at the foundry for melting recycled materials to be poured into green sand molds produced by match plate molding machines. Once the metal has been cast and shaken out, the products flow through the state of the art cleaning room (mill room) then on its way to the CNC machining centers.

Germans were able to locate radios in the medium frequency and take them under fire in seconds. "In all cases, it was the responsibility of the ship to determine whether any given shoot would endanger allied personnel or positions." This was possible because each bombarding ship was provided with an army officer who tracked positions of Allied forces ashore. Air spotters operated in pairs, one as a spotter, one as an escort, each capable of both missions.

Techmoan: Forgotten Format: The Sabamobil, YouTube, 22 June 2017 In the US, the player was offered for (equivalent to $ in ), a cassette was (equivalent to $ in ), and the adapter for installation in car was (equivalent to $ in ). The model TK-R12 also had an builtin medium frequency AM-broadcast receiver and could also be operated portable with five D-type batteries.(German) Sabamobil TK-R12, Radiomuseum.org, retrieved 24 June 2017 The drive assembly had no drive belts.

Two distinctly different sets of standards apply to powerline networking as of early 2010. Within homes, the HomePlug AV and IEEE 1901 standards specify how, globally, existing AC wires should be employed for data purposes. The IEEE 1901 includes HomePlug AV as a baseline technology, so any IEEE 1901 products are fully interoperable with HomePlug AV, HomePlug GreenPHY, and HomePlug AV2. On the other hand, medium-frequency home control devices remain divided, although X10 tends to be dominant.

It would seem probable that the Japanese signals bureau would be interested in reports of special fields, such as the 8th USAAF or Allied navigational procedures, that would have been furnished by the GDNA. In the last year of the war, and at the request of the Japanese, it was intended to send a German mission, comprising medium frequency and high frequency specialists to Japan. Strangely the Japanese were not interested in VHF or radar interception and jamming.

In telecommunication, a maritime broadcast communications net is a communications net that is used for international distress calling, including international lifeboat, lifecraft, and survival-craft high frequency (HF); aeronautical emergency very high frequency (VHF); survival ultra high frequency (UHF); international calling and safety very high frequency (VHF); combined scene-of-search-and-rescue; and other similar and related purposes. Note: Basic international distress calling is performed at either medium frequency (MF) or at high frequency (HF).

Experimental type X2159 was assigned to the development of a power tetrode by Eimac (then a division of Varian Associates) on May 28, 1970, and the design engineer was Sterling G. McNees. This electron tube was intended for use in very high power medium-frequency broadcast service and VLF communications equipment and as a pulse modulator (as a switch tube). The EIA (Electronic Industries Alliance) designation 8974 was assigned to this as it became a standard product. The initial technical data sheet was printed in July 1971.

The total weight of the shell was . They also had a Mk.4 thrower with homing torpedoes. Initially the ships were outfitted with one SPS-12 air search radar, one SPS-10B surface search radar, and one Sperry Mk.2 navigation radar. For sensing below the surface, the class was given one SQS-501 high frequency bottom profiler sonar, one SQS-502 high frequency mortar control sonar, one SQS-503 hull mounted active search sonar and one SQS-504 VDS medium frequency active search sonar.

Ionosondes transmit pulses of radio signals in the Medium Frequency (MF) and High Frequency (HF) ranges, whose echos are analyzed to measure height and density of the ionosphere. Advanced digital ionosondes used in the CHAIN network are also able to measure the bulk motion of ionospheric plasma. Most of the CHAIN instruments are located within the polar cap defined as a region of open magnetic field lines. The polar cap ionosphere is directly linked to the interplanetary magnetic field carried by the solar wind.

Edgar Allen's purchased Jessop's, relocating Jessop's special alloy (medium frequency) melting on Edgar's Sheffield Road site and the 3-ton electric furnace at their Imperial Steel Works melting shop. However a surprise bid for Osborn Hadfields Limited was announced on 24 October 1967 from Dunford & Elliott also of Sheffield and much smaller than Hadfields and Dunford's takeover of Hadfields was completed in December 1967 with effect from October 1967.Dunford & Elliott. The Times, Wednesday, May 01, 1968; pg. 22; Issue 57240 Samuel Osborn retained the foundry interests.

Grundig Satellit 400 solid-state, digital shortwave receiver, c. 1986 Shortwave radio is radio transmission using shortwave radio frequencies. There is no official definition of the band, but the range always includes all of the high frequency band (HF), which extends from 3–30 MHz (100 to 10 metres); above the medium frequency band (MF), to the bottom of the VHF band. Radio waves in the shortwave band can be reflected or refracted from a layer of electrically charged atoms in the atmosphere called the ionosphere.

Lower frequency radio waves, below 3 MHz, travel efficiently as ground waves. In ITU nomenclature, this includes (in order): medium frequency (MF), low frequency (LF), very low frequency (VLF), ultra low frequency (ULF), super low frequency (SLF), extremely low frequency (ELF) waves. Ground propagation works because lower-frequency waves are more strongly diffracted around obstacles due to their long wavelengths, allowing them to follow the Earth's curvature. Ground waves propagate in vertical polarization, with their magnetic field horizontal and electric field (close to) vertical.

The Eritrea Navy operate the outpost to observe the nearby waters for unwanted foreign visitors or vessels. They carry out patrols in the waters surrounding the island using dhows and skiffs. the forces personnel on the island spend 4–6 months on the island with the only contact with the outside world being via medium frequency radio to their headquarters just south of Massawa over 60 miles away. The island itself is a desert like environment with very little vegetation however the forces there do maintain herds of cows and goats.

Telenor Maritim Radio is a division of Telenor which provides maritime telecommunication services along the coast of Norway. It operates the civilian network of marine VHF radio, medium frequency and Navtex transmitters and five coast radio stations: Tjøme Radio, Rogaland Radio, Florø Radio, Bodø Radio and Vardø Radio. The agency also issues licenses for ship radios, including callsigns and Maritime Mobile Service Identities, and issues recreational and commercial radio operator certificates. Telenor Maritim Radio is based in Bergen, has 100 employees and a revenue of NOK 160 million Norwegian krone (NOK).

Morse encoded distress calling has saved thousands of lives since its inception almost a century ago, but its use requires skilled radio operators spending many hours listening to the radio distress frequency. Its range on the medium frequency (MF) distress band (500 kHz) is limited, and the amount of traffic Morse signals can carry is also limited. Not all ship-to-shore radio communications were short range. Some radio stations provided long-range radiotelephony services, such as radio telegrams and radio telex calls, on the HF bands (3–30 MHz) enabling worldwide communications with ships.

There are many different qualities in sound stimuli including loudness, pitch and timbre. The human ear is able to detect differences in pitch through the movement of auditory hair cells found on the basilar membrane. High frequency sounds will stimulate the auditory hair cells at the base of the basilar membrane while medium frequency sounds cause vibrations of auditory hair cells located at the middle of the basilar membrane. For frequencies that are lower than 200 Hz, the tip of the basilar membrane vibrates in sync with the sound waves.

The ozone layer absorbs 97 to 99 percent of the Sun's medium-frequency ultraviolet light (from about 200 nm to 315 nm wavelength), which otherwise would potentially damage exposed life forms near the surface. In 1976, atmospheric research revealed that the ozone layer was being depleted by chemicals released by industry, mainly chlorofluorocarbons (CFCs). Concerns that increased UV radiation due to ozone depletion threatened life on Earth, including increased skin cancer in humans and other ecological problems,An Interview with Lee Thomas, EPA's 6th Administrator. Video, Transcript (see p13).

As a stop gap measure, Russian Bronza (MG-345) hull mounted sonars are installed. Information released from the Severnoye Design Bureau (SDB) indicate that French towed array sonars (TAS) are also fitted. This is very plausible given that many Indian Navy ships now use French TAS, however INS Talwar shows no signs of such a system. The vessel may also have a Russian SSN-137 Variable Depth Sonar (VDS) with NATO reporting name Steer Hide, providing active search with medium frequency, and the sonar might be license produced in India with Indian designation SSSN-113.

Ground Wave propagation is a method of radio wave propagation that uses the area between the surface of the earth and the ionosphere for transmission. The ground wave can propagate a considerable distance over the earth's surface particularly in the low frequency and medium frequency portion of the radio spectrum. Ground wave radio signal propagation is ideal for relatively short distance propagation on these frequencies during the daytime. Sky-wave ionospheric propagation is not possible during the day because of the attenuation of the signals on these frequencies caused by the D region in the ionosphere.

As of 2015, the United States Air Force still trains ten people a year in Morse. The United States Coast Guard has ceased all use of Morse code on the radio, and no longer monitors any radio frequencies for Morse code transmissions, including the international medium frequency (MF) distress frequency of 500 kHz. However, the Federal Communications Commission still grants commercial radiotelegraph operator licenses to applicants who pass its code and written tests. Licensees have reactivated the old California coastal Morse station KPH and regularly transmit from the site under either this call sign or as KSM.

Ground conductivity is an extremely important factor in determining the field strength and propagation of surface wave (ground wave) radio transmissions. Low frequency (30–300 kHz) and medium frequency (300–3000 kHz) radio transmissions are particularly reliant on good ground conductivity as their primary propagation is by surface wave. It also affects the real world radiation pattern of high frequency (3-30 MHz) antennas, as the so called "takeoff angle" is not an inherent property of the antenna but a result of a ground reflection. For this reason ITU publishes an extensive world atlas of ground conductivities.

A 70 W antenna power emergency transmitter carried telegraph and radio telephone signals over 300–1,300 m wavelength bands. The main aerial consisted of two lead-weighted -long wires deployed by electric motor or hand crank; the emergency aerial was a wire stretched from a ring on the hull. Three six-tube receivers served the wavelengths from 120 to 1,200 m (medium frequency), 400 to 4,000 m (low frequency) and 3,000 to 25,000 m (overlapping low frequency and very low frequency). The radio room also had a shortwave receiver for 10 to 280 m (high frequency).

They also had a Mk.4 thrower with homing torpedoes. Initially the ships were outfitted with one SPS-12 air search radar, one SPS-10B surface search radar, and one Sperry Mk.2 navigation radar. For sensing below the surface, the class was given one SQS-501 high frequency bottom profiler sonar, one SQS-502 high frequency mortar control sonar, one SQS-503 hull mounted active search sonar and one SQS-504 VDS medium frequency active search sonar. For fire control purposes they were given one Mk 64 GFCS fire control with SPG-48 tracker (GUNAR).

The first airways to be delineated by radiofrequency were based on the old A-N system. The pilot listened for the stronger of the Morse codes transmitters ("· –" for "A" and "– ·" for "N", indicating left or right of the course); the objective was to be centered on course hearing a steady tone (the A and N Morse codes merge to form a steady tone when the receiver is equidistant from both transmitters). Later airways were based on low / medium frequency ground stations, like the beat frequency oscillator (BFO) and the non-directional beacon (NDB). These L/M frequency airways were the colored airways.

February saw HMS Veteran at Barrow- in Furness undergoing repair and refit. A Medium Frequency Direction Finder Outfit FM7 was fitted for navigation but was not useful against U-boats as they used a higher frequency for radio communications. Her refit and trials complete on 13 March. She resumed her duties in Atlantic convoy defence out of Londonderry. Later that month, on 20 March, she participated in the search for the German warships and In September 1941, she dropped depth charges on German U-boat at position 63°59'N, 34°48'W, which had attacked convoy SC 42.

Two types of modulation are used in analog radio broadcasting systems; AM and FM. In amplitude modulation (AM) the strength of the radio signal is varied by the audio signal. AM broadcasting is allowed in the AM broadcast bands which are between 148 and 283 kHz in the longwave range, and between 526 and 1706 kHz in the medium frequency (MF) range of the radio spectrum. AM broadcasting is also permitted in shortwave bands, between about 2.3 and 26 MHz, which are used for long distance international broadcasting. In frequency modulation (FM) the frequency of the radio signal is varied slightly by the audio signal.

There are various science historians, such as Belrose and Bradford, who have cast doubt that the Atlantic was bridged in 1901, but other science historians have taken the position that this was the first transatlantic radio transmission. Critics have claimed that it is more likely that Marconi received stray atmospheric noise from atmospheric electricity in this experiment.Hong, Sungook, "Marconi's Error: The First Transatlantic Wireless Telegraphy in 1901", Social Research, Spring 2005 (volume 72, number 1), pp. 107–124 The transmitting station in Poldhu, Cornwall used a spark-gap transmitter that could produce a signal in the medium frequency range and with high power levels.

According to the NTIA, the Coast Guard is the seventh-biggest user of radio spectrum in the United States. The U.S. Coast Guard maintains a network of VHF radio stations at its shore stations and on cutters and boats, as well as stations of the U.S. Coast Guard Auxiliary. In addition, the Coast Guard maintains a chain of high frequency (HF) and medium frequency (MF) radio stations that provide communications in the Atlantic and Pacific oceans, the Gulf of Mexico, and the Caribbean Sea. Coast Guard VHF Radio stations are currently being upgraded through the Rescue 21 program to meet the US obligations under the Global Maritime Distress Safety System.

The NARBA treaties have been substantially superseded by the "Regional Agreement for the Medium Frequency Broadcasting Service in Region 2" (Rio Agreement), which covers the entire Western hemisphere, and was signed at Rio de Janeiro, Brazil in 1981, taking effect on July 1, 1983 at 08:00 UTC. The interference protection criteria in the Rio Agreement are significantly different from NARBA's, and the concept of clear channel stations is eliminated. In adopting this agreement, the Bahamas and Canada declared their intent to renounce their adherence to NARBA. Bahamas and Canada announce their intent to renounce NARBA in Final Protocol statement No. 4 on page 88.

Groups were also built in Iceland, Nova Scotia and Jamaica. The anticipated improvements were not realised but later statistical work improved the system and the Goonhavern and Ford End groups continued to be used during the Cold War. The Royal Navy also deployed direction finding equipment on ships tasked to anti-submarine warfare in order to try to locate German submarines, e.g. Captain class frigates were fitted with a medium frequency direction finding antenna (MF/DF) (the antenna was fitted in front of the bridge) and high frequency direction finding (HF/DF, "Huffduff") Type FH 4 antenna (the antenna was fitted on top of the mainmast).

Reconstructed Reber Radio Telescope at National Radio Astronomy Observatory in Green Bank, West Virginia Starting in 1951, he received generous support from the Research Corporation in New York, and moved to Hawaii.Smithsonian/NASA bio In the 1950s, he wanted to return to active studies but much of the field was already filled with very large and expensive instruments. Instead he turned to a field that was being largely ignored, that of medium frequency (hectometre) radio signals in the 0.5–3 MHz range, around the AM broadcast bands. However, signals with frequencies below 30 MHz are reflected by an ionized layer in the Earth's atmosphere called the ionosphere.

Looking at distribution in Japan, it is seen particularly frequently in southern Kyushu, Nagasaki Prefecture, Okinawa and among the Ainu. And it is seen at medium frequency in the southern part of Shikoku, southern part of the Kii Peninsula, the Pacific side of the Tōhoku region (Sanriku) and Oki Islands. Overall, carriers of the ATL retrovirus were found to be more common in remote areas and remote islands. When examining the well-developed areas of ATL in each region of Kyushu, Shikoku, and Tōhoku in detail, carriers are preserved at high rates in small settlements that were isolated from the surroundings and inconvenient for traffic.

The LAB sonar array is water-backed—as opposed to earlier sonar arrays which were air- backed—and consists of a passive array and a medium-frequency active array. Compared to earlier Virginia-class submarines about 40% of the bow has been redesigned. South Dakota (SSN-790) will be equipped with a new propulsor, possibly the Hybrid Multi-Material Rotor (HMMR), developed by Defense Advanced Research Projects Agency (DARPA). The Hybrid Multi-Material Rotor program is an attempt to improve the design and manufacturing process of submarine propellers with an aim of reducing the cost and weight of the propeller/rotor as well as improving overall acoustic performance.

The D layer is the innermost layer, to above the surface of the Earth. Ionization here is due to Lyman series-alpha hydrogen radiation at a wavelength of 121.6 nanometre (nm) ionizing nitric oxide (NO). In addition, high solar activity can generate hard X-rays (wavelength ) that ionize N and O. Recombination rates are high in the D layer, so there are many more neutral air molecules than ions. Medium frequency (MF) and lower high frequency (HF) radio waves are significantly attenuated within the D layer, as the passing radio waves cause electrons to move, which then collide with the neutral molecules, giving up their energy.

New York: Elsevier, 672 pp. For example, the properties of the high-frequency flicker SSEP (whose peak amplitude is near 40–50 Hz) correspond to the properties of the subsequently discovered magnocellular neurons in the retina of the macaque monkey, while the properties of the medium-frequency flicker SSEP ( whose amplitude peak is near 15–20 Hz) correspond to the properties of parvocellular neurons. Since a SSEP can be completely described in terms of the amplitude and phase of each frequency component it can be quantified more unequivocally than an averaged transient evoked potential. It is sometimes said that SSEPs are elicited only by stimuli of high repetition frequency, but this is not generally correct.

A segmented marine worm Leocratides kimuraorum produces one of the loudest popping sounds in the ocean at 157 dB, frequencies 1-100 kHz, similar to the snapping shrimps. On the other side of the frequency spectrum are low frequency-vibrations, often not detected by hearing organs, but with other, less specialized sense organs. The examples include ground vibrations produced by elephants whose principal frequency component is around 15 Hz, and low- to medium-frequency substrate-borne vibrations used by most insect orders. Many animal sounds, however, do fall within the frequency range detectable by a human ear, between 20 and 20,000 Hz. Mechanisms for sound production and detection are just as diverse as the signals themselves.

The main sensor is the medium-frequency sonar mounted in the bow of the submarine, with passive and active modes, which is used for both search and attack. In addition, the system offers a method of underwater communications, and also functions as a torpedo approach warning system. This sonar is the Chinese development of French Thomson-CSF TSM-2233 sonar, and is capable of simultaneously tracking 4 to 12 targets depending on the function it is used for. To enhance passive search capabilities, a low frequency sonar of French Thomson-CSF TSM-2255 design is mounted on the flanks of the hull, with a maximum range in excess of 30 km and capable of simultaneously tracking four targets.

Previously known as WRIZ until 1985, the station had a phased array of four radio towers in Stiltsville south of Key Biscayne from 1967 to 1990. Because salt water is highly conductive, it makes an excellent ground plane for signals in the mediumwave radio band, allowing the station to travel farther on the same power, although this station's purpose was to put a strong signal across Miami while minimizing its signal toward the Bahamas Islands and a station on 1540.. As with all medium-frequency stations, the towers themselves were mast radiators, connected to the transmitter shack via transmission lines, held in this case a few feet above the water line by pilings.

But his proposal was primitive and not suitable for practical use. The first experiments with radio repeater stations to relay radio signals were done in 1899 by Emile Guarini-Foresio. However the low frequency and medium frequency radio waves used during the first 40 years of radio proved to be able to travel long distances by ground wave and skywave propagation. The need for radio relay did not really begin until the 1940s exploitation of microwaves, which traveled by line of sight and so were limited to a propagation distance of about by the visual horizon. In 1931 an Anglo-French consortium headed by Andre C. Clavier demonstrated an experimental microwave relay link across the English Channel using dishes.

Radio amateurs carried out the first shortwave transmissions over a long distance before Guglielmo Marconi. The name "shortwave" originated during the beginning of radio in the early 20th century, when the radio spectrum was divided into long wave (LW), medium wave (MW), and short wave (SW) bands based on the wavelength of the radio waves. Shortwave radio received its name because the wavelengths in this band are shorter than 200 m (1,500 kHz) which marked the original upper limit of the medium frequency band first used for radio communications. The broadcast medium wave band now extends above the 200 m / 1,500 kHz limit. Early long-distance radio telegraphy used long waves, below 300 kilohertz (kHz).

160 meters refers to the band of radio frequencies between 1.8 and 2 MHz, just above the mediumwave broadcast band. For many decades the lowest radio frequency band allocated for use by amateur radio, before the adoption, at the beginning of the 21st century in most countries, of the 630- and 2200-meter bands. Older amateur operators often refer to 160 meters as the Top Band"Top band" possibly refers to the position of 2 MHz very nearly at the top of the medium frequency band (MF); it is the highest amateur band within MF. It is also sometimes referred to as the "Gentleman's Band" in contrast to the often- freewheeling activity in the 80- and 20-meter bands.

Initially the ships were outfitted with one SPS-12 air search radar, one SPS-10B surface search radar, and one Sperry Mk.2 navigation radar. For sensing below the surface, the class was given one SQS-501 high frequency bottom profiler sonar, one SQS-502 high frequency mortar control sonar, one SQS-503 hull mounted active search sonar and one SQS-504 VDS medium frequency active search sonar. For fire control purposes they were given one Mk 64 GFCS fire control with SPG-48 tracker (GUNAR). The two Annapolis-class destroyers were built late enough to incorporate the helicopter hangar retrofitted to the St. Laurent class and the "Beartrap" haul-down device.

Up to nine special transmitters directed their signals at the beams in a manner that subtly widened their paths, making it harder for bomber crews to locate targets; confidence in the device was diminished by the time the Luftwaffe was ready to conduct big raids. German beacons operated on the medium-frequency band and the signals involved a two-letter Morse identifier followed by a lengthy time-lapse which enabled the Luftwaffe crews to determine the signal's bearing. The meacon system involved separate locations for a receiver with a directional aerial and a transmitter. The receipt of the German signal by the receiver was duly passed to the transmitter, the signal to be repeated.

It is also found at a medium frequency in Koreans, indigenous inhabitants of the Russian Far East, Aboriginal Australians and at moderate frequencies elsewhere throughout Asia and Oceania including Southeast Asia. Carriers of Haplogroup C among the ancient Jōmon people of Japan and Paleolithic and Neolithic Europeans carried C1a, C1b, and C1a2. Whereas Haplogroup D is found at high frequencies only amongst Tibetans, Japanese peoples, and Andaman Islanders, and has been found neither in India nor among the aboriginal inhabitants of the Americas or Oceania.崎谷満『DNA・考古・言語の学際研究が示す新・日本列島史』（勉誠出版 2009年）(in Japanese) According to Sakitani et al.

Previously known as D-M55, D-M64.1/Page44.1 (D1a2a) is found with high frequency among Ainu and with medium frequency among JapaneseYOUICHI SATO, TOSHIKATSU SHINKA, ASHRAF A. EWIS, AIKO YAMAUCHI, TERUAKI IWAMOTO, YUTAKA NAKAHORI of genetic variation in the Y chromosome of modern Japanese males. and Ryukyuans. Kim et al. (2011) found Haplogroup D-M55 in 2.0% (1/51) of a sample of Beijing Han and in 1.6% (8/506) of a pool of samples from South Korea, including 3.3% (3/90) from the Jeolla region, 2.4% (2/84) from the Gyeongsang region, 1.4% (1/72) from the Chungcheong region, 1.1% (1/87) from the Jeju region, 0.9% (1/110) from the Seoul-Gyeonggi region, and 0% (0/63) from the Gangwon region.

All had a normal control grid whose function was to act as a primary control for current passing through the tube, but they differed according to the intended function of the other grid. In order of historical appearance these are: the space-charge grid tube, the bi-grid valve, and the screen-grid tube. The last of these appeared in two distinct variants with different areas of application: the screen-grid valve proper, which was used for medium- frequency, small signal amplification, and the beam tetrode which appeared later, and was used for audio or radio-frequency power amplification. The former was quickly superseded by the rf pentode, while the latter was initially developed as an alternative to the pentode as an audio power amplifying device.

Radiofrequency ablation (RFA), also called fulguration, is a medical procedure in which part of the electrical conduction system of the heart, tumor or other dysfunctional tissue is ablated using the heat generated from medium frequency alternating current (in the range of 350–500 kHz). RFA is generally conducted in the outpatient setting, using either local anesthetics or conscious sedation anesthesia. When it is delivered via catheter, it is called radiofrequency catheter ablation. Two important advantages of radio frequency current (over previously used low frequency AC or pulses of DC) are that it does not directly stimulate nerves or heart muscle and therefore can often be used without the need for general anesthesia, and that it is very specific for treating the desired tissue without significant collateral damage.

When the current is stopped the copper tips cool the spot weld, causing the metal to solidify under pressure. The water cooled copper electrodes remove the surface heat quickly, accelerating the solidification of the metal, since copper is an excellent conductor. Resistance spot welding typically employs electrical power in the form of direct current, alternating current, medium frequency half-wave direct current, or high-frequency half wave direct current. If excessive heat is applied or applied too quickly, or if the force between the base materials is too low, or the coating is too thick or too conductive, then the molten area may extend to the exterior of the work pieces, escaping the containment force of the electrodes (often up to 30,000 psi).

A NAVTEX receiver prints an incoming message NAVTEX message for the Baltic Sea NAVTEX (NAVigational TEleX), sometimes styled Navtex or NavTex, is an international automated medium frequency direct-printing service for delivery of navigational and meteorological warnings and forecasts, as well as urgent maritime safety information (MSI) to ships. NAVTEX was developed to provide a low-cost, simple, and automated means of receiving this information aboard ships at sea within approximately 370 km (200 nautical miles) of shore. There are no user fees associated with receiving NAVTEX broadcasts, as the transmissions are typically transmitted from the National Weather Authority (Italy) or Navy or Coast Guard (as in the US) or national navigation authority (Canada). Where the messages contain weather forecasts, an abbreviated format very similar to the shipping forecast is used.

Austin ring transformer at the base of the WMCA and WNYC transmitter tower in alt= An Austin ring transformer is a special type of isolation transformer used for providing power to the aircraft warning lights and other devices on a mast radiator antenna insulated from ground. In the Austin transformer the primary and secondary windings are separated by an air gap, so that the high voltage on the mast cannot get into the low voltage lighting supply wiring, causing safety hazards. It is named after its inventor, Arthur O. Austin, who graduated from Stanford University in 1903 and who obtained 225 patents in his career.Austin insulators history, retrieved 2010 Nov 1 AM radio stations that broadcast in the medium frequency (MF) and low frequency (LF) bands typically use a type of antenna called a base-fed mast radiator.

The Beverage antenna or "wave antenna" is a long-wire receiving antenna mainly used in the low frequency and medium frequency radio bands, invented by Harold H. Beverage in 1921. It is used by amateur radio, shortwave listening, and longwave radio DXers and military applications. A Beverage antenna consists of a horizontal wire from one-half to several wavelengths long (hundreds of feet at HF to several kilometres for longwave) suspended above the ground, with the feedline to the receiver attached to one end, and the other end of the Beverage terminated through a resistor to ground., also archived here The antenna has a unidirectional radiation pattern with the main lobe of the pattern at a shallow angle into the sky off the resistor-terminated end, making it ideal for reception of long distance skywave (skip) transmissions from stations over the horizon which reflect off the ionosphere.

More depth charges were fitted on the upper deck of each side of the ship, allowing for about 200 in total; Royal Navy smoke floats were fitted above the depth charges in addition to the US Navy chemical smoke cylinders fitted to the stern of the Captains. A medium frequency direction finding antenna (MF/DF) was fitted in front of the bridge and a high-frequency direction finding (HF/DF, "Huffduff") Type FH 4 antenna was fitted on top of the mainmast; furthermore, a radio-receiving set tuned to the frequencies used for ship-to-ship communication by German U-boats and E-boats was fitted and a German-speaking rating carried. The Captains were eventually given Type 144 series Asdic (sonar) sets, an upgrade from the original Type 128D, and a Foxer was fitted to the aft of the Captains (and most other Atlantic escort vessels) during 1944 to counter the new acoustic torpedoes.

If far from resonance, the bottom two step down (high-in to low-out) circuits would instead be used to connect for a step up (low-in to high-out that is mostly reactance). The low- and high-pass versions of the four circuits shown in the top two rows use only one inductor and one capacitor. Normally, the low-pass would be preferred with a transmitter, in order to attenuate harmonics, but the high-pass configuration may be chosen if the components are more conveniently obtained, or if the radio already contains an internal low-pass filter, or if attenuation of low frequencies is desirable - for example when a local AM station broadcasting on a medium frequency may be overloading a high frequency receiver. In the bottom row, the Low R, high C circuit is shown feeding a short vertical antenna, such as would be the case for a compact, mobile antenna or otherwise on frequencies below an antenna's lowest natural resonant frequency.