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User:Thornfield Hall/Radio

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  • MF
    MF
  • File:HF
  • Comparison of the frequency bands defined by NATO, IEEE and ITU
    Comparison of the frequency bands defined by NATO, IEEE and ITU
  • FRS and GMRS frequency spectrum usage, including bandwidth and maximum power allowances.
    FRS and GMRS frequency spectrum usage, including bandwidth and maximum power allowances.
  • A schematic showing the relationship between dBu (the voltage source) and dBm (the power dissipated as heat by the 600 Ω resistor)
    A schematic showing the relationship between dBu (the voltage source) and dBm (the power dissipated as heat by the 600 Ω resistor)
  • Animation showing a half-wave dipole antenna receiving power from a radio wave. The antenna consists of two metal rods each one-quarter of the wavelength long, attached through a parallel transmission line to a resistance R equal to the characteristic impedance of the antenna, representing the receiver. The electromagnetic wave is represented by its electric field (E, green arrows) (it should be kept in mind that the drawing only shows the field along one line, while the radio wave is actually a plane wave and the electric field is actually the same at every point on a plane perpendicular to the direction of motion). The wave's magnetic field is not shown. The oscillating electric field exerts force on the electrons in the antenna rods , causing them to move back and forth in currents (black arrows) between the ends of the antenna rods, charging the ends of the antenna alternately positive (+) and negative (−). Since the antenna is a half-wavelength long at the radio wave's frequency, it excites standing waves of voltage (V, red) and current in the antenna. The voltage along the antenna elements is represented graphically by a band of red whose thickness at any point is proportional to the magnitude of the voltage. The oscillating currents flowing back and forth from one antenna element to the other, pass down the transmission line and through the radio receiver, represented by R. In this animation the action is shown slowed down drastically; the radio waves received by dipoles actually oscillate back and forth at tens of thousands to billions of cycles per second.
    Animation showing a half-wave dipole antenna receiving power from a radio wave. The antenna consists of two metal rods each one-quarter of the wavelength long, attached through a parallel transmission line to a resistance R equal to the characteristic impedance of the antenna, representing the receiver. The electromagnetic wave is represented by its electric field (E, green arrows) (it should be kept in mind that the drawing only shows the field along one line, while the radio wave is actually a plane wave and the electric field is actually the same at every point on a plane perpendicular to the direction of motion). The wave's magnetic field is not shown. The oscillating electric field exerts force on the electrons in the antenna rods , causing them to move back and forth in currents (black arrows) between the ends of the antenna rods, charging the ends of the antenna alternately positive (+) and negative (−). Since the antenna is a half-wavelength long at the radio wave's frequency, it excites standing waves of voltage (V, red) and current in the antenna. The voltage along the antenna elements is represented graphically by a band of red whose thickness at any point is proportional to the magnitude of the voltage. The oscillating currents flowing back and forth from one antenna element to the other, pass down the transmission line and through the radio receiver, represented by R. In this animation the action is shown slowed down drastically; the radio waves received by dipoles actually oscillate back and forth at tens of thousands to billions of cycles per second.
  • Animation showing standing waves on a half-wave dipole antenna driven by a sinusoidal voltage Vi from a radio transmitter at its resonant frequency. The oscillating voltage pushes the electrons back and forth along the two metal rods that make up the antenna, creating oscillating currents (blue arrows) in the antenna, charging its ends alternately positive (+) and negative (-). Since at this frequency the antenna is a half wavelength (λ/2) long, a sinusoidal wave of voltage or current takes exactly one cycle to make the round trip from one end of the antenna to the other and back, so the reflected waves reinforce each other. The antenna acts like an electronic resonater. Waves of current and voltage reflecting back and forth between the ends of the rods interfere to form standing waves, which radiate radio waves into space. The waves are shown graphically by bars of color (red for voltage V(x) and blue for current I(x)) whose width at each point is proportional to the amplitude of the wave at that point. The blue arrows show the direction of conventional current, flow of positive charge. The electrons oscillating back and forth in the antenne move in a direction opposite to the arrows. The action is shown slowed down enormously; the currents in an actual antenna oscillate back and forth 20 thousand to one billion times per second.
    Animation showing standing waves on a half-wave dipole antenna driven by a sinusoidal voltage Vi from a radio transmitter at its resonant frequency. The oscillating voltage pushes the electrons back and forth along the two metal rods that make up the antenna, creating oscillating currents (blue arrows) in the antenna, charging its ends alternately positive (+) and negative (-). Since at this frequency the antenna is a half wavelength (λ/2) long, a sinusoidal wave of voltage or current takes exactly one cycle to make the round trip from one end of the antenna to the other and back, so the reflected waves reinforce each other. The antenna acts like an electronic resonater. Waves of current and voltage reflecting back and forth between the ends of the rods interfere to form standing waves, which radiate radio waves into space. The waves are shown graphically by bars of color (red for voltage V(x) and blue for current I(x)) whose width at each point is proportional to the amplitude of the wave at that point. The blue arrows show the direction of conventional current, flow of positive charge. The electrons oscillating back and forth in the antenne move in a direction opposite to the arrows. The action is shown slowed down enormously; the currents in an actual antenna oscillate back and forth 20 thousand to one billion times per second.
  • Animation of a half-wave dipole antenna transmitting radio waves, showing the electric field lines. The dipole, in the center, consists of two vertical metal rods with an alternating current at its resonant frequency applied at its center from a radio transmitter (not shown) The voltage alternately charges the two ends of the antenna positive (+) and negative (−). Standing waves of current (red arrows) flow up and down the rods. The alternating voltage on the rods creates loops of electric field (black lines) that pinch off into closed loops and radiate away from the antenna at the speed of light. These are the radio waves. The radiated power is greatest in the horizontal direction, perpendicular to the antenna, and decreases to zero above and below the antenna, on the antenna axis. This picture only shows the electric field in a single plane through the antenna axis; the field is actually axially symmetrical about the antenna. The action is shown slowed down drastically in this animation; real radio waves oscillate at rates of thirty thousand to a billion cycles per second.
    Animation of a half-wave dipole antenna transmitting radio waves, showing the electric field lines. The dipole, in the center, consists of two vertical metal rods with an alternating current at its resonant frequency applied at its center from a radio transmitter (not shown) The voltage alternately charges the two ends of the antenna positive (+) and negative (−). Standing waves of current (red arrows) flow up and down the rods. The alternating voltage on the rods creates loops of electric field (black lines) that pinch off into closed loops and radiate away from the antenna at the speed of light. These are the radio waves. The radiated power is greatest in the horizontal direction, perpendicular to the antenna, and decreases to zero above and below the antenna, on the antenna axis. This picture only shows the electric field in a single plane through the antenna axis; the field is actually axially symmetrical about the antenna. The action is shown slowed down drastically in this animation; real radio waves oscillate at rates of thirty thousand to a billion cycles per second.
  • Animation showing how a Yagi-Uda antenna works. It consists of 4 half-wave dipole antennas in a line; a driven element (E) which is connected to the transmitter and radiates the radio waves, and 3 parasitic elements, two directors (D1, D2) and one reflector (R) which act as resonators, absorbing and reradiating the waves from the driven element with a different phase. The radio waves from all 4 elements combine and interfere, increasing the power radiated in the desired direction (up) and decreasing the power radiated in other directions. The radio waves from each individual element (wavy moving lines) are shown in a different color. The waves in the forward direction are in phase, and interfere constructively, adding together to produce a higher signal strength, while the waves in the reverse direction are out of phase, partially canceling each other to produce lower signal strength in that direction.
    Animation showing how a Yagi-Uda antenna works. It consists of 4 half-wave dipole antennas in a line; a driven element (E) which is connected to the transmitter and radiates the radio waves, and 3 parasitic elements, two directors (D1, D2) and one reflector (R) which act as resonators, absorbing and reradiating the waves from the driven element with a different phase. The radio waves from all 4 elements combine and interfere, increasing the power radiated in the desired direction (up) and decreasing the power radiated in other directions. The radio waves from each individual element (wavy moving lines) are shown in a different color. The waves in the forward direction are in phase, and interfere constructively, adding together to produce a higher signal strength, while the waves in the reverse direction are out of phase, partially canceling each other to produce lower signal strength in that direction.
  • Schematics of a simple Yagi-Uda antenna with just a driven dipole and a director and their emitted fields
    Schematics of a simple Yagi-Uda antenna with just a driven dipole and a director and their emitted fields
  • Diagram of ground dipole antenna used to transmit extremely low frequency (ELF) radio waves, showing how it works. This is modeled on the U.S. Navy ELF radio transmitter at Clam Lake, Wisconsin, which was used to communicate with submerged submarines at a frequency of 76 Hz from 1989 to 2004. The antenna consists of two electrodes buried in the Earth (G), 14 miles (23.5 km) apart, linked by overhead transmission lines resembling ordinary power distribution lines to a power plant transmitter (P). The system functions as a giant vertical loop antenna in which the earth serves as part of the loop. The power plant drives the antenna with 300 amperes alternating current at 76 Hz which flows through one transmission line, in looping currents (I) deep in bedrock from one ground electrode to the other, and back through the other transmission line (the drawing shows only one direction of the alternating current). The AC current creates an alternating magnetic field (H) which radiates ELF waves (yellow). The radiation pattern is directional, with two lobes (maxima) off the ends of the wire.
    Diagram of ground dipole antenna used to transmit extremely low frequency (ELF) radio waves, showing how it works. This is modeled on the U.S. Navy ELF radio transmitter at Clam Lake, Wisconsin, which was used to communicate with submerged submarines at a frequency of 76 Hz from 1989 to 2004. The antenna consists of two electrodes buried in the Earth (G), 14 miles (23.5 km) apart, linked by overhead transmission lines resembling ordinary power distribution lines to a power plant transmitter (P). The system functions as a giant vertical loop antenna in which the earth serves as part of the loop. The power plant drives the antenna with 300 amperes alternating current at 76 Hz which flows through one transmission line, in looping currents (I) deep in bedrock from one ground electrode to the other, and back through the other transmission line (the drawing shows only one direction of the alternating current). The AC current creates an alternating magnetic field (H) which radiates ELF waves (yellow). The radiation pattern is directional, with two lobes (maxima) off the ends of the wire.
  • Typical spectrum of extremely low frequency (ELF) electromagnetic oscillations in the Earth's atmosphere, showing peaks caused by the Schumann resonances. The Schuman resonances are the resonant frequencies of the spherical cavity bounded by the Earth and the ionosphere; lighning strikes and other sferics cause the Earth-ionosphere cavity to "ring" like a bell at these frequencies, causing peaks in the noise spectrum. The sharp power peak at 50 Hz is caused by radiation from global electric power grids. The rise of the noise at low frequencies (left side) is radio noise caused by slow processes in the Earth's magnetosphere.
    Typical spectrum of extremely low frequency (ELF) electromagnetic oscillations in the Earth's atmosphere, showing peaks caused by the Schumann resonances. The Schuman resonances are the resonant frequencies of the spherical cavity bounded by the Earth and the ionosphere; lighning strikes and other sferics cause the Earth-ionosphere cavity to "ring" like a bell at these frequencies, causing peaks in the noise spectrum. The sharp power peak at 50 Hz is caused by radiation from global electric power grids. The rise of the noise at low frequencies (left side) is radio noise caused by slow processes in the Earth's magnetosphere.
Band name Abbreviation ITU band number Frequency and wavelength Example uses
Extremely low frequency ELF 1 3–30 Hz
100,000–10,000 km		 Communication with submarines
Super low frequency SLF 2 30–300 Hz
10,000–1,000 km		 Communication with submarines
Ultra low frequency ULF 3 300–3,000 Hz
1,000–100 km		 Communication with submarines, communication within mines, landline telephony, fax machines, fiber-optic communication
Very low frequency VLF 4 3–30 kHz
100–10 km		 Navigation, time signals, communication with submarines, landline telephony, wireless heart rate monitors, geophysics
Low frequency LF 5 30–300 kHz
10–1 km		 Navigation, time signals, AM longwave broadcasting (Europe and parts of Asia), RFID, amateur radio.
Medium frequency MF 6 300–3,000 kHz
1,000–100 m		 AM (medium-wave) broadcasts, amateur radio, avalanche beacons, magnetic resonance imaging, positron emission tomography, electrical telegraph, wireless telegraphy, radioteletype, dial-up internet.
High frequency HF 7 3–30 MHz
100–10 m		 Shortwave broadcasts, citizens band radio, amateur radio, over-the-horizon aviation communications, RFID, over-the-horizon radar, automatic link establishment (ALE) / near-vertical incidence skywave (NVIS) radio communications, marine and mobile radio telephony, CT scan, magnetic resonance imaging, positron emission tomography, ultrasound, cordless phones.
Very high frequency VHF 8 30–300 MHz
10–1 m		 FM broadcasts, television broadcasts, cable television broadcasting, radars, line-of-sight ground-to-aircraft, aircraft-to-aircraft communications, emergency locator beacon homing signal, radioteletype, land mobile and maritime mobile communications, amateur radio, police, fire and emergency medical services scanners, weather radio, CT scan, magnetic resonance imaging, positron emission tomography, ultrasound, cordless phones.
Ultra high frequency UHF 9 300–3,000 MHz
100–10 cm		 Television broadcasts, cable television broadcasting, microwave oven, radars, microwave devices/communications, radio astronomy, radars (L band), mobile phones, wireless LAN, Bluetooth, Zigbee, GPS and two-way radios such as land mobile, emergency locator beacon, FRS and GMRS radios, amateur radio, satellite radio, police, fire and emergency medical services scanners, remote control systems, ADSB, cordless phones, internet, dial-up internet, satellite broadcasting, communication satellites, weather satellites, satellite phones (L band), satellite phones (S band).
Super high frequency SHF 10 3–30 GHz
10–1 cm		 Radio astronomy, microwave devices/communications, wireless LAN, DSRC, most modern radars, communications satellites, cable and satellite television broadcasting, DBS, amateur radio, satellite broadcasting, communication satellites, weather satellites, satellite radio, cordless phones, internet, satellite phones (S band).
Extremely high frequency EHF 11 30–300 GHz
10–1 mm		 Radio astronomy, satellite broadcasting, communication satellites, weather satellites, high-frequency microwave radio relay, microwave remote sensing, directed-energy weapon, millimeter wave scanner, Wireless Lan 802.11ad, internet.
Terahertz or tremendously high frequency THF 12 300–3,000 GHz
1–0.1 mm		 Experimental medical imaging to replace X-rays, ultrafast molecular dynamics, condensed-matter physics, terahertz time-domain spectroscopy, terahertz computing/communications, remote sensing

GMRS Frequency table

[edit]
Frequency Channel FRS power FRS
bandwidth		 GMRS power GMRS
bandwidth		 Notes
462.5625 MHz 1 2 W 12.5 kHz 5 W 20 kHz (1)(4)(5)
462.5875 MHz 2 2 W 12.5 kHz 5 W 20 kHz (1)(4)(5)
462.6125 MHz 3 2 W 12.5 kHz 5 W 20 kHz (1)(4)(5)
462.6375 MHz 4 2 W 12.5 kHz 5 W 20 kHz (1)(4)(5)
462.6625 MHz 5 2 W 12.5 kHz 5 W 20 kHz (1)(4)(5)
462.6875 MHz 6 2 W 12.5 kHz 5 W 20 kHz (1)(4)(5)
462.7125 MHz 7 2 W 12.5 kHz 5 W 20 kHz (1)(4)(5)
467.5625 MHz 8 0.5 W 12.5 kHz 0.5 W 12.5 kHz (1)(4)(6)
467.5875 MHz 9 0.5 W 12.5 kHz 0.5 W 12.5 kHz (1)(4)(6)
467.6125 MHz 10 0.5 W 12.5 kHz 0.5 W 12.5 kHz (1)(4)(6)
467.6375 MHz 11 0.5 W 12.5 kHz 0.5 W 12.5 kHz (1)(4)(6)
467.6625 MHz 12 0.5 W 12.5 kHz 0.5 W 12.5 kHz (1)(4)(6)
467.6875 MHz 13 0.5 W 12.5 kHz 0.5 W 12.5 kHz (1)(4)(6)
467.7125 MHz 14 0.5 W 12.5 kHz 0.5 W 12.5 kHz (1)(4)(6)
462.5500 MHz 15 2 W 12.5 kHz 50 W 20 kHz (2)(5)
462.5750 MHz 16 2 W 12.5 kHz 50 W 20 kHz (2)(5)
462.6000 MHz 17 2 W 12.5 kHz 50 W 20 kHz (2)(5)
462.6250 MHz 18 2 W 12.5 kHz 50 W 20 kHz (2)(5)
462.6500 MHz 19 2 W 12.5 kHz 50 W 20 kHz (2)(5)
462.6750 MHz 20 2 W 12.5 kHz 50 W 20 kHz (2)(5)(7)
462.7000 MHz 21 2 W 12.5 kHz 50 W 20 kHz (2)(5)
462.7250 MHz 22 2 W 12.5 kHz 50 W 20 kHz (2)(5)
467.5500 MHz 15R — — 50 W 20 kHz (3)(5)
467.5750 MHz 16R — — 50 W 20 kHz (3)(5)
467.6000 MHz 17R — — 50 W 20 kHz (3)(5)
467.6250 MHz 18R — — 50 W 20 kHz (3)(5)
467.6500 MHz 19R — — 50 W 20 kHz (3)(5)
467.6750 MHz 20R — — 50 W 20 kHz (3)(5)
467.7000 MHz 21R — — 50 W 20 kHz (3)(5)
467.7250 MHz 22R — — 50 W 20 kHz (3)(5)
Table notes
(1) Shared FRS and GMRS simplex.
(2) Shared FRS and GMRS simplex; GMRS repeater output.
(3) GMRS repeater input. The output frequency of this repeater input is the input frequency minus 5 MHz.
(4) FRS transmissions are limited to bandwidth of 11 kHz with a transmitter deviation of +/- 2.5 kHz. Channels are on 12.5 kHz centers.
(5) GMRS transmissions may have a bandwidth of 16 kHz with a transmitter deviation of +/- 5.0 kHz. Channels are on 25 kHz centers.
(6) GMRS transmissions are limited to a bandwidth of 11 kHz with a transmitter deviation of +/- 2.5 kHz. Channels are on 12.5 kHz centers.
(7) National GMRS calling channel (CTCSS tone 141.3 Hz).

MURS

[edit]
Channel Frequency Maximum
authorized bandwidth 		Channel name
1 151.82 MHz 11.25 kHz MURS 1
2 151.88 MHz 11.25 kHz MURS 2
3 151.94 MHz 11.25 kHz MURS 3
4 154.57 MHz 20.00 kHz Blue Dot
5 154.60 MHz 20.00 kHz Green Dot

Marine VHF

[edit]

A marine VHF set is a combined transmitter and receiver and only operates on standard, international frequencies known as channels. Channel 16 (156.8 MHz) is the international calling and distress channel. Transmission power ranges between 1 and 25 watts, giving a maximum range of up to about 60 nautical miles (111 km) between aerials mounted on tall ships and hills, and 5 nautical miles (9 km; 6 mi) between aerials mounted on small boats at sea level.[1] Frequency modulation (FM) is used, with vertical polarization, meaning that antennas have to be vertical in order to have good reception. For longer range communication at sea, marine MF and marine HF bands and satellite phones can be used.

Half-duplex channels here are listed with the A and B frequencies the same. The frequencies, channels, and some of their purposes are governed by the ITU. For an authoritative list see.[2] The original allocation of channels consisted of only channels 1 to 28 with 50 kHz spacing between channels, and the second frequency for full-duplex operation 4.6 MHz higher.

Improvements in radio technology later meant that the channel spacing could be reduced to 25 kHz with channels 60 to 88 interspersed between the original channels.

Channels 75 and 76 are omitted as they are either side of the calling and distress channel 16, acting as guard channels. The frequencies which would have been the second frequencies on half-duplex channels are not used for marine purposes and can be used for other purposes that vary by country. For example, 161.000 to 161.450 MHz are part of the allocation to the Association of American Railroads channels used by railways in the US and Canada.[3] [4]

Channel
number 		Frequencies (MHz)  United Kingdom [5]  United States  Canada  Australia  New Zealand  Finland [6]  Europe CEPT[7] Mediterranean countries
(sea, ocean) 		 Belgium
 France
 Germany
 Netherlands
CCNR: main stem, river, canal, lake, pond, estuary [8][9]
 A  Ship tx, usually  B  Shore tx, usually
0 156.000 160.600 Private, coast guard  A 
1 156.050 160.650 Ship-to-ship/shore, commercial and safety
West Coast  A 
 Public Correspondence (Ship-to-Shore full-duplex)
BC Coast 		Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks
Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways.. (Ship-to-Shore full-duplex)
2 156.100 160.700 Public
BC Coast 		Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks
Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways.. (Ship-to-Shore full-duplex)
3 156.150 160.750  A  Illegal for public use[a] Public
BC Coast/Inland 		Boat to Boat - Kawau Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks, Customs Coast Guard, search and rescue
Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways. (Ship-to-Shore full-duplex)
4 156.200 160.800 Ship-to-ship/shore, commercial and safety
East Coast and Inland  A 

Canadian Coast Guard - public working channel
BC Coast[b]  A 

Boat to Boat - Tutukaka/Raglan Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks, Customs Coast Guard, search and rescue
Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks
5 156.250 160.850 Ship Movements Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks, authorities responsible
Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways.. (Ship-to-Shore full-duplex)
6 156.300 156.300 Ship-to-ship + Ship-to-Air  A  Ship-to-ship + Ship-to-Air  A  Distress - Ship-to-Air Working - Internship  A  Ship-to-ship (commercial)
also SAR: Ship-to-Ship + Ship-to-Air 		Ship-to-ship + Ship-to-Air  A  Ship-to-ship (limited to 1 watt) + Ship-to-Air
7 156.350 160.950 General working channel Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Navy Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways.. (Ship-to-Shore full-duplex)
8 156.400 156.400 Ship-to-ship  A  Ship-to-ship
East and west coasts,
Lake Winnipeg  A  		Working - Internship Working - Internship  A  Ship-to-ship (commercial)  A  Ship-to-ship  A  Ship-to-ship (limited to 1 watt)
9 156.450 156.450 Frequently used by pilots  A  Calling  A , commercial and non-commercial. Ship-to-air for maritime support
Atlantic and BC coasts  A  		Pilots, Port Operations Port Operations  A  VTS
Ship-to-ship + Port Operations 		Marina pilots, Marina Operations, Ship in a marina Marina pilots, Marina Operations, Ship in a marina (limited to 1 watt)
10 156.500 156.500 Frequently used by HM Coastguard  A  Ship-to-air - SAR and antipollution  A 
General working -
Atlantic and BC coasts,
Great Lakes 		Port Operations  A  Ship-to-ship
Port Operations
also SAR and oil cleanup
only VTS on Gulf of Finland 		International waters Ship-to-ship ; Customs Coast Guard, Navy Calling ; Ship-to-ship ; Customs, On board working (limited to 1 watt) Distress, safety and calling
11 156.550 156.550 Port Operations VTS - BC Coast
Pilotage  A  		Port Operations  A  Port Operations, also the Saimaa Canal locks Navy Port Operations
12 156.600 156.600 Port Operations VTS - San Francisco offshore
Pilotage  A  		VTS - BC Coast
Port and pilot ops  A  		Port Operations, VTS Port Operations  A  Port Operations Commercial port operations, fishing port operations, pilots, Ship in a fishing port, Ship in a Commercial port
13 156.650 156.650 Bridge-to-Bridge Working  A  Bridge-to-Bridge safety  A : Vessels > 20m must maintain watch, Tx limited to 1 watt. Movable bridge / lock operations. VTS - BC Coast
Bridge-to-bridge safety  A  		Port Operations, VTS Internship Nav Safety  A  Pilots
Ship-to-ship
Port Operations 		Port Operations, Coast Guard Ship-to-ship (limited to 1 watt)
14 156.700 156.700 Port Operations VTS - San Francisco Bay and Delta
Pilotage  A  		VTS - BC Coast
Port and pilot ops  A  		Port Operations  A  Working channel for SAR authorities, Turku Radio
(Port Operations) 		Port Operations, Navy Port Operations
15 156.750 156.750 On board working (limited to 1 watt)  A   A  max 1 W
Intraship
Ship-to-ship
Port Operations 		beach monitoring Radiocommunications on board a ship or in a group of boats towed or pushed, as well as those concerning the instructions for the maneuver bullish and docking. (limited to 1 watt)
16 156.800 156.800 International distress, safety and calling  A 
All vessels equipped with VHF must maintain watch. 		Estuary (16 + 10). Not used on: Main stem, River, Canal, Lake, Pond.
17 156.850 156.850 On board Working  A  Aquatic Sports Events  A  max 1 W
Intraship
Ship-to-ship
Port Operations 		Port Operations, Navy, Maritime Gendarmerie Radiocommunications on board a ship or in a group of boats towed or pushed, as well as those concerning the instructions for the maneuver bullish and docking. (limited to 1 watt)
18 156.900 161.500 Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks
Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
19 156.950 161.550 Landside facilities: harbormaster, marinas. Canadian Coast Guard - Working Channel Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Port Operations Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
20 157.000 161.600 Repeater Operations Continuous Weather
Maritime Safety Service 		Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Port Operations, Public Correspondence (Ship-to-Shore full-duplex)
Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex),
(limited to 1 watt Paris Underground canal)
21 157.050 161.650  A  U.S. Coast Guard Only Continuous marine broadcasts  B 
(WX 8) 		Continuous Weather
Maritime Safety Service 		Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Port Operations
22 157.100 161.700  A  U.S. Coast Guard—public working channel[c] Continuous Weather
Maritime Safety Service 		Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Port Operations, Public Correspondence (Ship-to-Shore full-duplex)
Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
23 157.150 161.750 HM Coastguard Maritime Safety Information - Now on 62,63,64  A  U.S. Coast Guard Only Continuous Weather
Maritime Safety Service 		Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Port Operations, Public Correspondence (Ship-to-Shore full-duplex)
Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex), Independent radio networks
24 157.200 161.800 UKSAR G/A Winching  A 
UKSAR TWC  B [d] 		Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
25 157.250 161.850 Maritime Radio Working Channel Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
26 157.300 161.900 HM Coastguard Maritime Safety Information Public correspondence (marine telephone operator) Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
27 157.350 161.950 Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
28 157.400 162.000 Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
31 157.550 162.150 (The Netherlands) Marina channel
Public Correspondence (Ship-to-Shore full-duplex)
M1/37A 157.850 157.850 (As M1) Yacht clubs, race committees and marinas
60 156.025 160.625 GOFREP on Gulf of Finland
Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
61 156.075 160.675  A  Illegal for public use[a] GOFREP (Estonia) on Gulf of Finland
Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
62 156.125 160.725 HM Coastguard Maritime Safety Information[d] Boat to Boat - Waiheke/Whangaroa Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Public Correspondence (Ship-to-Shore full-duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
63 156.175 160.775 HM Coastguard Maritime Safety Information (half-duplex)[d] Boat to Boat - Manukau Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Coast Guard, Port Operations Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
64 156.225 160.825 HM Coastguard Maritime Safety Information (half-duplex)[d]  A  Illegal for public use[a] Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Coast Guard, Port Operations Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore full-duplex)
65 156.275 160.875 National Coastwatch Institution (NCI) and Independent Coastwatch Stations (http://www.seasafetygroup.org) Working Channel for communication with local mariners for radio checks and local sea conditions. Effective 1 March 2021. Marine Assistance Working Channel Boat to Boat - Coromandel Public Correspondence (Ship-to-Shore full-duplex)
Port Operations 		Coast Guard, Port Operations Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
66 156.325 160.925 Marinas - BC Coast  A  Public Correspondence (Ship-to-Shore Duplex)
Port Operations 		Public Correspondence (Ship-to-Shore Duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
67 156.375 156.375 UK Small Ship Safety Channel Working Channel, Marine Weather Maritime Radio Working Channel  A  VTS
(Ship-to-ship + Port Operations) 		Coast Guard Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
68 156.425 156.425 Non-commercial  A  Maritime Radio Working Channel  A  Port Operations, Border Guard authorities,

also some yacht clubs and marinas

Coast Guard Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
69 156.475 156.475 Port Operations Non-commercial  A  Australian Navy Maritime Radio Working channel
Surf Lifesaving 		 A  Ship-to-ship
Port Operations 		Navy Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
70 156.525 156.525 Digital Selective Calling  A  Not used on: Main stem, River, Canal, Lake, Pond.
71 156.575 156.575 Port Operations Non-commercial  A  Maritime Radio Working Channel  A  VTS
(Ship-to-ship + Port Operations) Port Operations 		Navy Port Operations
72 156.625 156.625 Ship-to-ship  A Frequently used by leisure craft Non-commercial ship-to-ship  A  Ship-to-ship  A  Ship-to-ship
Ship-to-air 		 A  Ship-to-ship, communications with a social (ship)  A  Ship-to-ship, communications with a social (ship) (limited to 1 watt)
73 156.675 156.675 HM Coastguard Safety Broadcasts

Backup Small Ship Safety

Ship-to-ship Marinas - Working  A  Ship-to-ship

Ship-to-air
(Port Operations) 		Port Operations, Navy Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
74 156.725 156.725 British Waterways/Canal and River Trust Channel (Canal and River System)

Port Operations

Ship-to-ship Working - Coast/Ship  A  Port Operations Port Operations, Navy, Maritime Gendarmerie Port Operations
75 156.775 156.775 Navigation related communications (limited to 1 watt)  A Restricted
Ship-to-ship
Port Operations 		 A Restricted
Ship-to-ship
Port Operations, (limited to 1 watt) 		Port Operations
76 156.825 156.825  A  Restricted
Port Operations 		 A Restricted
Ship-to-ship
Port Operations, (limited to 1 watt) 		Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
77 156.875 156.875 Ship-to-ship  A  Ship-to-ship  A  Ship-to-ship  A  Ship-to-ship, communications with a social (ship)  A  Ship-to-ship, communications with a social (ship) (limited to 1 watt)
78 156.925 161.525 Non-commercial  A  Public Correspondence (Ship-to-Shore Duplex)
Port Operations 		Public Correspondence (Ship-to-Shore Duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
79 156.975 161.575 Public Correspondence (Ship-to-Shore Duplex)
Port Operations 		Customs Coast Guard, search and rescue, Port Operations Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
80 157.025 161.625 UK Marina Channel Repeater Operations Coastguard Radio - Working Channel GOFREP on Gulf of Finland
Public Correspondence (Ship-to-Shore Duplex)
Port Operations 		Customs, Coast Guard, search and rescue, Port Operations Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
81 157.075 161.675  A  U.S. Government Use Only Repeater Operations Coastguard Radio - Working Channel GOFREP (Estonia) on Gulf of Finland
Public Correspondence (Ship-to-Shore Duplex)
Port Operations 		Public Correspondence (Ship-to-Shore Duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
82 157.125 161.725  A  U.S. Government Use Only Canadian Coast Guard - Working Channel Coastguard Radio - Working Channel Public Correspondence (Ship-to-Shore Duplex)
Port Operations 		Port Operations Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
83 157.175 161.775  A  U.S. Coast Guard Use Only Canadian Coast Guard - Working Channel Public Correspondence (Ship-to-Shore Duplex)
Port Operations 		Public Correspondence (Ship-to-Shore Duplex)
Port Operations 		Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
84 157.225 161.825 HM Coastguard Maritime Safety Information - Now on 62,63,64 Coastguard Radio - Working Channel Public Correspondence (Ship-to-Shore Duplex)
Port Operations 		Public Correspondence (Ship-to-Shore Duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
85 157.275 161.875 UKSAR TWC (half-duplex)[d] Radio Telephone - full duplex Coastguard Radio - Working Channel Public Correspondence (Ship-to-Shore Duplex)
Port Operations 		Navy Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
86 157.325 161.925 HM Coastguard Maritime Safety Information- Now on 62,63,64 Coastguard Radio - Working Channel Public Correspondence (Ship-to-Shore Duplex)
Port Operations 		Navy Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
87 157.375 157.375 Public Correspondence
Port Operations 		Public Correspondence (Ship-to-Shore Duplex), Independent radio networks, Customs Coast Guard, search and rescue Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
88 157.425 157.425 Commercial, Internship only. Public Correspondence (Ship-to-Shore Duplex), Independent radio networks Radiotelephone links between ship stations and land stations of the authorities responsible for the operation of inland waterways (Ship-to-Shore Duplex)
M2/P4 161.425 161.425 (As M2) Yacht clubs, race committees and marinas (As P4) In France, some yacht clubs, marinas and race committees
87B 161.975 161.975 Automatic Identification System  A  B 
88B 162.025 162.025 Automatic Identification System  A  B 
L1 155.500 155.500 Leisure activities.

(Ship-to-ship) Used in the Nordic countries and Estonia

L2 155.525 155.525 Leisure activities.

(Ship-to-ship) Used in the Nordic countries and Estonia

L3 155.650 155.650 Leisure activities.

(Ship-to-ship) Used in Finland and Norway

F1 155.625 155.625 Fishing.

(Ship-to-ship) Used in the Nordic countries

F2 155.775 155.775 Fishing.

(Ship-to-ship) Used in the Nordic countries

F3 155.825 155.825 Fishing, also recreational fishing

(Ship-to-ship) Used in the Nordic countries

  1. ^ a b c Some radios enable channels 3A, 61A, and 64A when configured for "USA mode" even though those channels are allocated exclusively for Public Safety use by the FCC. The frequencies 156.075, 156.150, and 156.225 MHz are used for interoperability communication by police and fire departments in many areas.
  2. ^ CCG public operations moved from 22A to 04A to avoid interference from USCG stations in northern Washington state.
  3. ^ Channel 22A is reserved for communication between the U.S. Coast Guard vessels and private vessels. The Coast Guard does not monitor 22A: Contact must first be established on 16.
  4. ^ a b c d e UKSAR land-based search and rescue teams have access to the half-duplexed versions of 24, 62, 63, 64, 85 for operational and training needs. These include mountain rescue teams in England, Wales and Scotland.


dBm

[edit]
Power level Power Notes
526 dBm 3.6×1049 W Black hole collision, the power radiated in gravitational waves following the collision GW150914, estimated at 50 times the power output of all the stars in the observable universe.[10][11]
420 dBm 1×1039 W Cygnus A, one of the most powerful radio sources in the sky
296 dBm 3.846×1026 W Total power output of the Sun[12]
120 dBm 1 GW Experimental high-power microwave (HPM) generation system, 1GW at 2.32 GHz for 38 ns[13]
105 dBm 32 MW AN/FPS-85 Phased Array Space Surveillance Radar, claimed by the US Space Force as the most powerful radar in the world.[14]
95.5 dBm 3,600 kW High-frequency Active Auroral Research Program maximum power output, the most powerful shortwave station in 2012
80 dBm 100 kW Typical transmission power of FM radio station with 50-kilometre (31 mi) range
62 dBm 1.588 kW = 1,588 W 1,500 W is the maximal legal power output of a US ham radio station.[15]
60 dBm 1 kW = 1,000 W Typical combined radiated RF power of microwave oven elements
55 dBm ~300 W Typical single-channel RF output power of a Ku band geostationary satellite
50 dBm 100 W Typical total thermal radiation emitted by a human body, peak at 31.5 THz (9.5 μm)

Typical maximal output RF power from a ham radio HF transceiver

40 dBm 10 W Typical power-line communication (PLC) transmission power
37 dBm 5 W Typical maximal output RF power from a handheld ham radio VHF/UHF transceiver
36 dBm 4 W Typical maximal output power for a citizens band radio station (27 MHz) in many countries
33 dBm 2 W Maximal output from a UMTS/3G mobile phone (power class 1 mobiles)

Maximal output from a GSM850/900 mobile phone

30 dBm 1 W = 1000 mW

DCS or GSM 1,800/1,900 MHz mobile phone. EIRP IEEE 802.11a (20 MHz-wide channels) in either 5 GHz subband 2 (5,470–5,725 MHz) provided that transmitters are also IEEE 802.11h-compliant, or U-NII-3 (5,725–5,825 MHz). The former is EU only, the latter is US only. Also, maximal power allowed by the FCC for American amateur radio licensees to fly radio-controlled aircraft or operate RC models of any other type on the amateur radio bands in the US.[16]

29 dBm 794 mW
28 dBm 631 mW
27 dBm 500 mW Typical cellular phone transmission power

Maximal output from a UMTS/3G mobile phone (power class 2 mobiles)

26 dBm 400 mW
25 dBm 316 mW
24 dBm 251 mW Maximal output from a UMTS/3G mobile phone (power class 3 mobiles)

1,880–1,900 MHz DECT (250 mW per 1,728 kHz channel). EIRP for wireless LAN IEEE 802.11a (20 MHz-wide channels) in either the 5 GHz subband 1 (5,180–5,320 MHz) or U-NII-2 and -W ranges (5,250–5,350 MHz & 5,470–5,725 MHz, respectively). The former is EU only, the latter is US only.

23 dBm 200 mW EIRP for IEEE 802.11n wireless LAN 40 MHz-wide (5 mW/MHz) channels in 5 GHz subband 4 (5,735–5,835 MHz, US only) or 5 GHz subband 2 (5,470–5,725 MHz, EU only). Also applies to 20 MHz-wide (10 mW/MHz) IEEE 802.11a wireless LAN in 5 GHz subband 1 (5,180–5,320 MHz) if also IEEE 802.11h-compliant (otherwise only 3 mW/MHz → 60 mW when unable to dynamically adjust transmission power, and only 1.5 mW/MHz → 30 mW when a transmitter also cannot dynamically select frequency).
22 dBm 158 mW
21 dBm 125 mW Maximal output from a UMTS/3G mobile phone (power class 4 mobiles)
20 dBm 100 mW EIRP for IEEE 802.11b/g wireless LAN 20 MHz-wide channels in the 2.4 GHz Wi-Fi/ISM band (5 mW/MHz).

Bluetooth Class 1 radio. Maximal output power from unlicensed AM transmitter per US FCC rules 15.219[17]

19 dBm 79 mW
18 dBm 63 mW
17 dBm 50 mW
15 dBm 32 mW Typical wireless LAN transmission power in laptops
10 dBm 10 mW
7 dBm 5.0 mW Common power level required to test the automatic gain control circuitry in an AM receiver
6 dBm 4.0 mW
5 dBm 3.2 mW
4 dBm 2.5 mW Bluetooth Class 2 radio, 10 m range
3 dBm 2.0 mW
2 dBm 1.6 mW
1 dBm 1.3 mW
0 dBm 1.0 mW = 1000 μW Bluetooth standard (Class 3) radio, 1 m range
−1 dBm 794 μW
−3 dBm 501 μW
−5 dBm 316 μW
−10 dBm 100 μW Maximal received signal power of wireless network (802.11 variants)
−13 dBm 50.12 μW Dial tone for the precise tone plan found on public switched telephone networks in North America
−20 dBm 10 μW
−30 dBm 1.0 μW = 1000 nW
−40 dBm 100 nW
−50 dBm 10 nW
−60 dBm 1.0 nW = 1000 pW The Earth receives one nanowatt per square metre from a magnitude +3.5 star[18]
−70 dBm 100 pW
−73 dBm 50.12 pW "S9" signal strength, a strong signal, on the S meter of a typical ham or shortwave radio receiver
−80 dBm 10 pW
−100 dBm 0.1 pW Minimal received signal power of wireless network (802.11 variants)
−111 dBm 0.008 pW = 8 fW Thermal noise floor for commercial GPS single-channel signal bandwidth (2 MHz)
−127.5 dBm 0.178 fW = 178 aW Typical received signal power from a GPS satellite
−174 dBm 0.004 aW = 4 zW Thermal noise floor for 1 Hz bandwidth at room temperature (20 °C)
−192.5 dBm 0.056 zW = 56 yW Thermal noise floor for 1 Hz bandwidth in outer space (4 kelvins)
−∞ dBm 0 W Zero power is not well-expressed in dBm (value is negative infinity)
  1. ^ "MGN 324 Operational guidance on the use of radio and automatic identification systems". Gov.uk. Retrieved 16 February 2015.
  2. ^ Circular letter CM/19-E, International Telecommunication Union, 27 March 2009
  3. ^ "American Association of Railroads channel allocation" (PDF). Arrl-al.org. Archived from the original (PDF) on 20 September 2010. Retrieved 23 September 2013.
  4. ^ "U.S. VHF Channels". Navcen.uscg.gov. Retrieved 16 February 2015.
  5. ^ Noice, Alison, ed. (2008). VHF Radio (including GMDSS) (2nd ed.). RYA. ISBN 978-1-906435-20-2.
  6. ^ "Kommunikationsverket 2010: Handbok i VHF-radiokommunikation för radiooperatör med kusttrafikcertifikat" (PDF). Viestintavirasto.fi. Retrieved 16 February 2015.
  7. ^ MANUEL DE PREPARATION DU CRR MARITIME 2015 Agence nationale des fréquences
  8. ^ Guide de radiotéléphonie pour la navigation intérieure 2014: Commission Centrale pour la Navigation du Rhin
  9. ^ MANUEL DE PREPARATION DU CRR FLUVIAL 2015 Agence nationale des fréquences
  10. ^ "OBSERVATION OF GRAVITATIONAL WAVES FROM A BINARY BLACK HOLE MERGER" (PDF). LSC (Ligo Scientific Collaboration). Caltech. 2015. Archived (PDF) from the original on 2022-10-09. Retrieved 10 April 2021.
  11. ^ "Found! Gravitational Waves, or a Wrinkle in Spacetime". National Geographic. National Geographic. 2016-02-11. Retrieved 2021-04-10.
  12. ^ "Ask Us: Sun". Cosmicopia. NASA. 2012. Archived from the original on 2000-08-16. Retrieved 13 July 2017.
  13. ^ Li, Wei; Li, Zhi-qiang; Sun, Xiao-liang; Zhang, Jun (2015-11-01). "A reliable, compact, and repetitive-rate high power microwave generation system". Review of Scientific Instruments. 86 (11): 114704. Bibcode:2015RScI...86k4704L. doi:10.1063/1.4935500. ISSN 0034-6748. PMID 26628156.
  14. ^ "AN/FPS-85". US Air Force Fact Sheet. United States Dept. of Defense. Retrieved May 19, 2017.
  15. ^ "Part 97 - Amateur Radio". ARRL. Archived from the original on 2012-10-09. Retrieved 2012-09-21.
  16. ^ [1] Archived 2016-12-22 at the Wayback Machine FCC Part 97 Amateur Radio Service - Rule 97.215, Telecommand of model craft, section (c).
  17. ^ FCC Web Documents citing 15.219 Archived 2011-11-06 at the Wayback Machine.
  18. ^ "Radiant Flux of a Magnitude +3.5 Star". Archived from the original on 2012-06-30. Retrieved 2009-07-22.
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