What can you hear? Go to my posts and you will see what you can listen to?
For part TWO
Even many communications in 2023 use satellites we have internet, smart phones, etc. Betwen zero and 30 MHz we can hear many things.
Low frequency
Low frequency (LF) is the ITU designation[1] for radio frequencies (RF) in the range of 30–300 kHz. Since its wavelengths range from 10–1 km, respectively, it is also known as the kilometre band or kilometre wave.
LF radio waves exhibit low signal attenuation, making them suitable for long-distance communications. In Europe and areas of Northern Africa and Asia, part of the LF spectrum is used for AM broadcasting as the "longwave" band. In the western hemisphere, its main use is for aircraft beacon, navigation (LORAN), information, and weather systems. A number of time signal broadcasts also use this band. The main mode of transmission used in this band is ground waves, in which LF radio waves travel just above the Earth's surface, following the terrain. LF ground waves can travel over hills, and can travel beyond the horizon, up to several hundred kilometers from the transmitter.
https://en.wikipedia.org/wiki/Radio_spectrum
For ELF to VLF please visit the blog http://www.vlf.it/
https://en.wikipedia.org/wiki/Low_frequency
From Ø to 30 Hz exept the navy of many countries
Look the web sdr from Netherlands
147.3
List of VLF-transmitters
- Europe 1 - 183 kHz.
- France inter - 162 kHz (France, Pays limitrophes, Afrique du Nord)
- RMC INFO - 216 kHz.
- RTL - 234 kHz.
- Medi 1 - 171 kHz.
- BBC 4 - 198 kHz.
- RTE 1 - 252 kHz.
- Radio Alger - 252 kHz.
Europe 1, formerly known as Europe n° 1, is a privately owned radio station created in 1955.[1] Owned and operated by Lagardère Active, a subsidiary of the Lagardère Group, it is one of the leading radio broadcasting stations in France and its programmes can be received throughout the country. In January 2022 the conservative media mogul Vincent Bolloré took over the station.[2]
Long wave for radios in AM are only few on longue wave now. In Europe many famous radios stations have close but are in FM. France Inter, RTL, Europe is now only a souvenir...
Now we stil have in Europe: Romania on 153 kHz, BBC radio 4 on 198 kHz, Poland on 225 kHz, and few more.
Longwave is used for broadcasting only within ITU Region 1. The long-wave broadcasters are located in western, northern, central, and southeastern Europe, the former Soviet Union, Mongolia, Algeria, and Morocco.
Typically, a larger geographic area can be covered by a long-wave broadcast transmitter compared to a medium-wave one. This is because ground-wave propagation suffers less attenuation due to ground conductivity at lower frequencies.[10]
Many countries have stopped using LW for broadcasting because of low audience figures, a lack of LW on new consumer receivers, increasing interference levels, the energy inefficiency of AM and high electricity costs at transmitters.
In 2014 and 2015 Russia closed all of its LW broadcast transmitters.[11]
By 2023 several LW frequencies were unoccupied and some of the remaining services are scheduled for closure.
DR Langbølge (Denmark) is scheduled to stop broadcasting on December 31, 2023.[12] BBC Radio 4 (UK) announced that it will stop LW broadcasts 2024.[13] RÚV Rás (Iceland) is also scheduled to stop
broadcasting in 2024.
The 630-meter (or 600-meter) amateur radio band is a frequency band allocated by the International Telecommunication Union (ITU) to amateur radio operators, and it ranges from 472–479 kHz, or equivalently 625.9–635.1 meters wavelength. It was formally allocated to amateurs at the 2012 World Radiocommunication Conference (WRC-12). The band is available on a secondary basis in all ITU regions with the limitation that amateur stations have maximum radiated power of 1 watt effective isotropic radiated power (EIRP); however, stations more than 800 km (500 miles) from certain countries[a] may be permitted to use 5 watts EIRP.[2][3][4]
http://www.larc.ca/PDF/meetings/VE3OTLowBands.pdf
From 1974 to 1991 the tallest ever manmade structure stood here, the Warsaw radio mast. This mast was a 646.38-metre-high (2,120.7 ft) guyed radio mast in steel-framework construction with triangular cross section with a side length of 4.8 metres and a weight of 420 tons. The mast was used for the 2000 kilowatt long wave transmitter of the Polish broadcasting authority as aerial and was therefore insulated against ground for a voltage of 120 kilovolts. It collapsed during renovation work on August 8, 1991. Nobody was reported killed in the accident.
https://de.wikipedia.org/wiki/Langwellenrundfunk
http://www.mwlist.org/mwlist_quick_and_easy.php?area=1&kHz=0
Non-directional beacon
http://www.ndblist.info/ndbphotos/beaconpics.htm
Now between 280 kHz and 535 kHz here in Europe there is the non-directional beacons
NDBs typically operate in the frequency range from 190 kHz to 535 kHz
Besides their use in aircraft navigation, NDBs are also popular with long-distance radio enthusiasts (DXers). Because NDBs are generally low-power (usually 25 watts, some can be up to 5 kW), they normally cannot be heard over long distances, but favorable conditions in the ionosphere can allow NDB signals to travel much farther than normal. Because of this, radio DXers interested in picking up distant signals enjoy listening to faraway NDBs. Also, since the band allocated to NDBs is free of broadcast stations and their associated interference, and because most NDBs do little more than transmit their Morse code callsign, they are very easy to identify, making NDB monitoring an active niche within the DXing hobby.
In North America, the NDB band is from 190 to 435 kHz and from 510 to 530 kHz. In Europe, there is a longwave broadcasting band from 150 to 280 kHz, so the European NDB band is from 280 kHz to 530 kHz with a gap between 495 and 505 kHz because 500 kHz was the international maritime distress (emergency) frequency.
The beacons that transmit between 510 kHz and 530 kHz can sometimes be heard on AM radios that can tune below the beginning of the medium wave (MW) broadcast band. However, reception of NDBs generally requires a radio receiver that can receive frequencies below 530 kHz. Often "general coverage" shortwave radios receive all frequencies from 150 kHz to 30 MHz, and so can tune to the frequencies of NDBs. Specialized techniques (receiver preselectors, noise limiters and filters) are required for the reception of very weak signals from remote beacons.[8]
The best time to hear NDBs that are very far away is the last three hours before sunrise. Reception of NDBs is also usually best during the fall and winter because during the spring and summer, there is more atmospheric noise on the LF and MF bands.
I can listen to the NDB LMA in Germany ( in Morse code )
https://ourairports.com/navaids/LMA/Lima_NDB_DE/
You need to know the 24 letters of the alphabet
They are also some NAVTEX
NAVTEX (NAVigational TEleX), sometimes styled Navtex or NavTex,[1] 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) off-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.
NAVTEX is a component of the International Maritime Organization/International Hydrographic Organization Worldwide Navigation Warning Service (WWNWS). NAVTEX is also a major element of the Global Maritime Distress Safety System (GMDSS). SOLAS Convention mandated certain classes of vessels must carry NAVTEX, beginning August 1, 1993.
NAVTEX messages are transmitted using binary frequency-shift keying (BFSK) at 100 bit/s and a 170 Hz frequency shift
So you can use a KIWI SDR to décode messages in FSK mode
Frequency-shift keying (FSK) is a frequency modulation scheme in which digital information is encoded on a carrier signal by periodically shifting the frequency of the carrier between several discrete frequencies.[1] The technology is used for communication systems such as telemetry, weather balloon radiosondes, caller ID, garage door openers, and low frequency radio transmission in the VLF and ELF bands. The simplest FSK is binary FSK (BFSK), in which the carrier is shifted between two discrete frequencies to transmit binary (0s and 1s) information.[2]
https://en.wikipedia.org/wiki/List_of_Navtex_stations
Medium wave
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 more limited sound quality than FM stations on the FM broadcast band. During the daytime, reception is usually limited to more local stations, though this is dependent on the signal conditions and quality of radio receiver used. Improved signal propagation at night allows the reception of much longer distance signals (within a range of about 2,000 km or 1,200 miles). This can cause increased interference because on most channels multiple transmitters operate simultaneously worldwide. In addition, amplitude modulation (AM) is often more prone to interference by various electronic devices, especially power supplies and computers. Strong transmitters cover larger areas than on the FM broadcast band but require more energy and longer antennas. Digital modes are possible but have not reached momentum yet.
MW was the main radio band for broadcasting from the beginnings in the 1920s into the 1950s until FM with a better sound quality took over. In Europe, digital radio is gaining popularity and offers AM stations the chance to switch over if no frequency in the FM band is available, (however digital radio still has coverage issues in many parts of Europe). Many countries in Europe have switched off or limited their MW transmitters since the 2010s.
The term is a historic one, dating from the early 20th century, when the radio spectrum was divided on the basis of the wavelength of the waves into long wave (LW), medium wave, and short wave (SW) radio bands.
For Europe, Africa and Asia the MW band consists of 120 channels with carrier frequencies from 531–1602 kHz spaced every 9 kHz. Frequency coordination avoids the use of adjacent channels in one area. The total allocated spectrum including the modulated audio ranges from 526.5–1606.5 kHz.[1] Australia uses an expanded band up to 1701 kHz.
North America uses 118 channels from 530–1700 kHz[2] using 10 kHz spaced channels. The range above 1610 kHz is primarily only used by low-power stations; it is the preferred range for services with automated traffic, weather, and tourist information.
Few stations can use the same fréquencies and the web sdr cant turn is antenna !!!
Radio Caroline is SIO 555
I have another blog for SWL the radios in AM long wave, medium and short wave
https://webkiwisdrswl.blogspot.com/
| LTU | Radio Baltic Waves International NHK World 0330-0350 ru, NHK World 0330-0350 ru [Mo-Fr], Radio Poland 0400-0500 be, Radio Poland 0500-0530 uk, Radio Poland 1200-1300 en, NHK World 1500-1510 ru [Mo-Fr], NHK World 1500-1520 ru [SaSu], NHK World 1510-1525 en [Mo-Fr], NHK World 1520-1530 en [SaSu], NHK World 1525-1530 ru [Mo-Fr], Radio Poland 1530-1600 pl, Radio Poland 1600-1630 ru, Radio Poland 1630-1700 de, NHK World 1700-1750 en [SaSu], NHK World 1730-1750 ru, Deutshe Welle 1800-1830 ru, Radio Liberty 1830-2100 ru, Radio Ukraine International 2100-0330 uk |
A very exotic radio from England who play India music with 125 KW on 1458 kHz
| G | Lyca Radio 1458 24h | Brookmans Park/4 wire T aerial * |
Marine Weather Forecasts
List of Pirate Radio Frequencies
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