simply RED
May 5th, 2006, 08:07 AM
The electromagnetic spectrum is a wide and useful tool. It offers:
- communication (radio and wireless internet)
- remote control (like radio detonators)
- radiotelemetry
- microwave and laser weaponry
and much more!
With this topic I would like to start a quest for it (quest for information - do {not} get me wrong :P)!
Logic suggests, the first base to capture is the simplest radio communication.
Here is a small plan conspect. Feel free to add constructive criticism and suggestions! Directly to the topic of course! Note that to this point good scematics source (for homemade apparature) do not exist. Schematics of all kinds of radio devices are welcome! To this point I do not have any high tech schematics, so schematics plus brief explanations how they work will be most welcome!!!
The word "ham" is not going to be used unless for hystorical reference - because practics suggests - the air is not a place for kewls !!!
1. Electromagnetic spectrum
2. HF communication
3. 10-16 HF band
4. UHF transmission
5. Traceless radio communication
6. Apparature and schematics
-antennas
-transmitters
-receivers
-additional apparature
7. High tech
The idea is every point of the plan conspect to be posted in separate topic with "(EMW)" - Electromagnetic Warfare in front. N1 - El spectrum is posted here. I will be very happy if somebody posts his interpretation of (N7 for example) as a completed work :) ! As it is very slow so much info to be translated from Russian into English (my literature is not in English) - I got it raw from I-net, corrected if anything wrong and added missing parts and necessary comments.
Electromagnetic Spectrum
Welcome to the battlefield! This is your theritory where long distance interference is possible!
If you do not want to stick in cliffs - prepare useful map! Learn how to trespass the underwater reefs!
Radio spectrum:
ELF 3Hz - 30Hz
SLF 30Hz - 300Hz
ULF 300Hz - 3kHz
VLF 3kHz - 30kHz
LF 30kHz - 300kHz
MF 300kHz - 3MHz
HF 3MHz - 30MHz
VHF 30MHz - 300MHz
UHF 300MHz - 3GHz
SHF 3GHz - 30GHz
EHF 30GHz - 300GHz
Extremely low frequency (ELF) is the band of radio frequencies from 3 to 30 Hz.
ELF was used by the US Navy and Soviet/Russian Navy to communicate with submerged submarines. Because of the electrical conductivity of salt water, submarines are shielded from most electromagnetic communications. Signals in the ELF frequency range, however, can penetrate much more deeply. Two factors limit the usefulness of ELF communications channels; the low data transmission rate of a few characters per minute, and to a lesser extent the one-way nature caused by the impracticality of installing the huge transmitter on a submarine. Generally ELF signals were used to order a submarine to rise to a shallow depth where it could receive some other form of communication. ELF radiation is suspected psycho and physico active.
Super Low Frequency (SLF) is the frequency range between 30 hertz and 300 hertz. This frequency range includes the frequencies of AC power grids (50 hertz and 60 hertz).
The radio services Saguine (USA) on 76 hertz and ZEVS (Russia) on 82 hertz operate in this range, which is often incorrectly called Extremely Low Frequency (ELF). They both provide communication services for submarines at depth.
Ultra Low Frequency (ULF) is the frequency range between 300 hertz and 3000 hertz.
This band is used for communications in mines, as it can penetrate the earth.
Very low frequency or VLF refers to radio frequencies (RF) in the range of 3 to 30 kHz. Since there is not much bandwidth in this band of the radio spectrum, only the very simplest signals are used, such as for radionavigation. Because VLF waves can penetrate water only to a depth of roughly 10 to 40 metres (30 to 130 feet), depending on the frequency and the salinity of the water, they are used to communicate with submarines near the surface. (ELF is used for fully submerged vessels.)
Low Frequency or LF (sometimes called longwave) refers to Radio Frequencies (RF) in the range of 30–300 kHz. In Europe, part of the LF spectrum is used for AM broadcast service.
Mediumwave radio transmissions (sometimes called Medium frequency or MF) are those between the frequencies of 300*kHz and 3000*kHz. This band has too low frequency for modern communication.
High frequency (HF) radio frequencies are between 3 and 30 MHz. This range is often called shortwave.
This is the first band usable for radio communication that should arrise our attention!
Since the ionosphere often reflects HF radio waves quite well, this range is extensively used for medium and long range radio communication. However, suitability of this portion of the spectrum for such communication varies greatly with a complex combination of factors:
Sunlight/darkness at site of transmission and reception
Transmitter/receiver proximity to terminator
Season
Sunspot cycle
Solar activity
Polar aurora
Maximum usable frequency
Lowest usable high frequency
Frequency of operation within the HF range
The high frequency band WAS (the organized radio ham society is DEAD) very popular with amateur radio operators, who took advantage of direct, long-distance (often inter-continental) communications and the "thrill factor" resulting from making contacts in variable conditions. International shortwave broadcasting utilizes this set of frequencies, as well as a seemingly declining number of "utility" users (marine, aviation, military, and diplomatic interests), who have, in recent years, been swayed over to less volatile means of communication (for example, via satellites), but may maintain HF stations after switch-over for back-up purposes. CB radios operate in the higher portion of the range (around 27 MHz).
10MHz is going to be the lowest frequency we could use if professional communication is necessarey. Hope far UV will be the highest :) .
The range between 10 and 16 MHz is the best part of the short waves and will be exploited later!
Very high frequency (VHF) is the radio frequency range from 30 MHz (wavelength 10 m) to 300 MHz (wavelength 1 m).
Common uses for VHF are FM radio broadcast at 88–108 MHz .
VHF frequencies' propagation characteristics are ideal for short-distance terrestrial communication, with a range generally somewhat farther than line-of-sight from the transmitter (see formula below). Unlike high frequencies (HF), the ionosphere does not usually reflect VHF radio and thus transmissions are restricted to the local area (400km max) (and don't interfere with transmissions thousands of kilometres away). VHF is also less affected by atmospheric noise and interference from electrical equipment than low frequencies. Whilst it is more easily blocked by land features than HF and lower frequencies, it is less bothered by buildings and other less substantial objects than higher frequencies.
Two unusual propagation conditions can allow much farther range than normal. The first, tropospheric ducting, can occur in front of and parallel to an advancing cold weather front, especially if there is a marked difference in humidities between the cold and warm air masses. A duct can form approximately 150 miles (240 km with 5W.) in advance of the cold front, much like a ventilation duct in a building, and VHF radio frequencies can travel along inside the duct, bending or refracting, for hundreds of miles.
It is easy to construct efficient antennas for it. The band 100-1500 MHz is a golden mine for easy-to-set communications and will be exploited later.
Ultra high frequency (UHF) designates a range (band) of electromagnetic waves whose frequency is between 300 MHz (Wavelength 1 meter) and 3.0 GHz (Wavelength 10 centimetres) .
Like VHF this band allows communication in the „visible“ area. Above 2000MHz the transmission could be affected by moisture in the air and other negative factors but the affection is less than in the upper bands.
(SHF) Frequency band between 3 GHz and 30 GHz
Aka microwaves. Actually the microwave range includes ultra-high frequency
(UHF) (0.3-3 GHz), super high frequency (SHF) (3-30 GHz), and extremely high frequency (EHF) (30-300 GHz) signals.
Generation
Microwaves can be generated by a variety of means, generally divided into two categories: solid state devices and vacuum-tube based devices. Solid state microwave devices are based on semiconductors such as silicon or gallium arsenide, and include field-effect transistors (FET's), bipolar junction transistors (BJT's), Gunn diodes, and IMPATT diodes. Specialized versions of standard transistors have been developed for higher speed which are commonly used in microwave applications. Microwave variants of BJT's include the heterojunction bipolar transistor (HBT), and microwave variants of FET's include the MESFET, the HEMT (also known as HFET), and LDMOS transistor. Vacuum tube based devices operate on the ballistic motion of electrons in a vacuum under the influence of controlling electric or magnetic fields, and include the magnetron, klystron, traveling wave tube (TWT), and gyrotron.
Microwaves are used in bluetooth, microwave oven, radar and other applications.
High amplitude microwaves are dangerous for the health. There are real microwave weapons developed by both Russia and USA during the cold war. Psychoactive frequencies are presented within the band.
Extremely high frequency is the highest radio frequency band. EHF runs the range of frequencies from 30 to 300 gigahertz, above which electromagnetic radiation is considered to be low (or far) infrared light. This band has a wavelength of one to ten millimetres, giving it the name millimeter band.
Radio signals in this band are extremely prone to atmospheric attenuation, making them of very little use over long distances. Even over relatively short distances, rain fade is a serious problem, caused when absorption by rain reduces signal strength.
This band is commonly used in radio astronomy.
Infrared
The term "infrared" refers to a broad range of frequencies, beginning at the top end of those frequencies used for communication and extending up the the low frequency (red) end of the visible spectrum. The wavelength range is from about 1 millimeter down to 750 nm. The range adjacent to the visible spectrum is called the "near infrared" and the longer wavelength part is called "far infrared". IR radiation is assicated with vibrational energy change. If there is a chance for vibrational redistribution of electric charge (change of the dipole moment) – the molecule absorbs in certain IR frequency/ies.
Frequencies: .003 - 4 x 10exp14 Hz
Wavelengths: 1 mm - 750 nm
Quantum energies: 0.0012 - 1.65 eV
Visible Light
The narrow visible part of the electromagnetic spectrum corresponds to the wavelengths near the maximum of the Sun's radiation curve. In interactions with matter, visible light primarily acts to set elevate electrons to higher energy levels
Frequencies: 4 - 7.5 x 10exp14 Hz
Wavelengths: 750 - 400 nm
Quantum energies: 1.65 - 3.1 eV
Ultraviolet
The region just below the visible in wavelength is called the near ultraviolet. It is absorbed very strongly by most solid substances, and even absorbed appreciably by air. The shorter wavelengths reach the ionization energy for many molecules, so the far ultraviolet has some of the dangers attendent to other ionizing radiation. The tissue effects of ultraviolet include sunburn, but can have some therapeutic effects as well. The sun is a strong source of ultraviolet radiation, but atmospheric absorption eliminates most of the shorter wavelengths. The eyes are quite susceptible to damage from ultraviolet radiation. Welders must wear protective eye shields because of the uv content of welding arcs can inflame the eyes. Snow-blindness is another example of uv inflamation; the snow reflects uv while most other substances absorb it strongly.
Frequencies: 7.5 x 10exp14 - 3 x 10exp16 Hz
Wavelengths: 400 nm - 10 nm
Quantum energies: 3.1 - 124 eV
X-Rays
Are high frequency electromagnetic rays which are produced when the electrons are suddenly decelerated - these rays are called bremsstrahlung radiation, or "braking radiation". X-rays are also produced when electrons make transitions between lower atomic energy levels in heavy elements. X-rays produced in this way have have definite energies just like other line spectra from atomic electrons. They are called characteristic x-rays since they have energies determined by the atomic energy levels.
In interactions with matter, x-rays are ionizing radiation and produce physiological effects which are not observed with any exposure of non-ionizing radiation, such as the risk of mutations or cancer in tissue.
Frequencies: 3 x 10exp16 Hz upward
Wavelengths: 10 nm - > downward
Quantum energies: 124 eV -> upward
Gamma-Rays
Gamma are higly energetic rays.
In interactions with matter, gamma rays are ionizing radiation and produce physiological effects which are not observed with any exposure of non-ionizing radiation, such as the risk of mutations or cancer in tissue.
Frequencies: typically >10exp20 Hz
Wavelengths: typically < 10exp-12 m
Quantum energies: typically >1 MeV
- communication (radio and wireless internet)
- remote control (like radio detonators)
- radiotelemetry
- microwave and laser weaponry
and much more!
With this topic I would like to start a quest for it (quest for information - do {not} get me wrong :P)!
Logic suggests, the first base to capture is the simplest radio communication.
Here is a small plan conspect. Feel free to add constructive criticism and suggestions! Directly to the topic of course! Note that to this point good scematics source (for homemade apparature) do not exist. Schematics of all kinds of radio devices are welcome! To this point I do not have any high tech schematics, so schematics plus brief explanations how they work will be most welcome!!!
The word "ham" is not going to be used unless for hystorical reference - because practics suggests - the air is not a place for kewls !!!
1. Electromagnetic spectrum
2. HF communication
3. 10-16 HF band
4. UHF transmission
5. Traceless radio communication
6. Apparature and schematics
-antennas
-transmitters
-receivers
-additional apparature
7. High tech
The idea is every point of the plan conspect to be posted in separate topic with "(EMW)" - Electromagnetic Warfare in front. N1 - El spectrum is posted here. I will be very happy if somebody posts his interpretation of (N7 for example) as a completed work :) ! As it is very slow so much info to be translated from Russian into English (my literature is not in English) - I got it raw from I-net, corrected if anything wrong and added missing parts and necessary comments.
Electromagnetic Spectrum
Welcome to the battlefield! This is your theritory where long distance interference is possible!
If you do not want to stick in cliffs - prepare useful map! Learn how to trespass the underwater reefs!
Radio spectrum:
ELF 3Hz - 30Hz
SLF 30Hz - 300Hz
ULF 300Hz - 3kHz
VLF 3kHz - 30kHz
LF 30kHz - 300kHz
MF 300kHz - 3MHz
HF 3MHz - 30MHz
VHF 30MHz - 300MHz
UHF 300MHz - 3GHz
SHF 3GHz - 30GHz
EHF 30GHz - 300GHz
Extremely low frequency (ELF) is the band of radio frequencies from 3 to 30 Hz.
ELF was used by the US Navy and Soviet/Russian Navy to communicate with submerged submarines. Because of the electrical conductivity of salt water, submarines are shielded from most electromagnetic communications. Signals in the ELF frequency range, however, can penetrate much more deeply. Two factors limit the usefulness of ELF communications channels; the low data transmission rate of a few characters per minute, and to a lesser extent the one-way nature caused by the impracticality of installing the huge transmitter on a submarine. Generally ELF signals were used to order a submarine to rise to a shallow depth where it could receive some other form of communication. ELF radiation is suspected psycho and physico active.
Super Low Frequency (SLF) is the frequency range between 30 hertz and 300 hertz. This frequency range includes the frequencies of AC power grids (50 hertz and 60 hertz).
The radio services Saguine (USA) on 76 hertz and ZEVS (Russia) on 82 hertz operate in this range, which is often incorrectly called Extremely Low Frequency (ELF). They both provide communication services for submarines at depth.
Ultra Low Frequency (ULF) is the frequency range between 300 hertz and 3000 hertz.
This band is used for communications in mines, as it can penetrate the earth.
Very low frequency or VLF refers to radio frequencies (RF) in the range of 3 to 30 kHz. Since there is not much bandwidth in this band of the radio spectrum, only the very simplest signals are used, such as for radionavigation. Because VLF waves can penetrate water only to a depth of roughly 10 to 40 metres (30 to 130 feet), depending on the frequency and the salinity of the water, they are used to communicate with submarines near the surface. (ELF is used for fully submerged vessels.)
Low Frequency or LF (sometimes called longwave) refers to Radio Frequencies (RF) in the range of 30–300 kHz. In Europe, part of the LF spectrum is used for AM broadcast service.
Mediumwave radio transmissions (sometimes called Medium frequency or MF) are those between the frequencies of 300*kHz and 3000*kHz. This band has too low frequency for modern communication.
High frequency (HF) radio frequencies are between 3 and 30 MHz. This range is often called shortwave.
This is the first band usable for radio communication that should arrise our attention!
Since the ionosphere often reflects HF radio waves quite well, this range is extensively used for medium and long range radio communication. However, suitability of this portion of the spectrum for such communication varies greatly with a complex combination of factors:
Sunlight/darkness at site of transmission and reception
Transmitter/receiver proximity to terminator
Season
Sunspot cycle
Solar activity
Polar aurora
Maximum usable frequency
Lowest usable high frequency
Frequency of operation within the HF range
The high frequency band WAS (the organized radio ham society is DEAD) very popular with amateur radio operators, who took advantage of direct, long-distance (often inter-continental) communications and the "thrill factor" resulting from making contacts in variable conditions. International shortwave broadcasting utilizes this set of frequencies, as well as a seemingly declining number of "utility" users (marine, aviation, military, and diplomatic interests), who have, in recent years, been swayed over to less volatile means of communication (for example, via satellites), but may maintain HF stations after switch-over for back-up purposes. CB radios operate in the higher portion of the range (around 27 MHz).
10MHz is going to be the lowest frequency we could use if professional communication is necessarey. Hope far UV will be the highest :) .
The range between 10 and 16 MHz is the best part of the short waves and will be exploited later!
Very high frequency (VHF) is the radio frequency range from 30 MHz (wavelength 10 m) to 300 MHz (wavelength 1 m).
Common uses for VHF are FM radio broadcast at 88–108 MHz .
VHF frequencies' propagation characteristics are ideal for short-distance terrestrial communication, with a range generally somewhat farther than line-of-sight from the transmitter (see formula below). Unlike high frequencies (HF), the ionosphere does not usually reflect VHF radio and thus transmissions are restricted to the local area (400km max) (and don't interfere with transmissions thousands of kilometres away). VHF is also less affected by atmospheric noise and interference from electrical equipment than low frequencies. Whilst it is more easily blocked by land features than HF and lower frequencies, it is less bothered by buildings and other less substantial objects than higher frequencies.
Two unusual propagation conditions can allow much farther range than normal. The first, tropospheric ducting, can occur in front of and parallel to an advancing cold weather front, especially if there is a marked difference in humidities between the cold and warm air masses. A duct can form approximately 150 miles (240 km with 5W.) in advance of the cold front, much like a ventilation duct in a building, and VHF radio frequencies can travel along inside the duct, bending or refracting, for hundreds of miles.
It is easy to construct efficient antennas for it. The band 100-1500 MHz is a golden mine for easy-to-set communications and will be exploited later.
Ultra high frequency (UHF) designates a range (band) of electromagnetic waves whose frequency is between 300 MHz (Wavelength 1 meter) and 3.0 GHz (Wavelength 10 centimetres) .
Like VHF this band allows communication in the „visible“ area. Above 2000MHz the transmission could be affected by moisture in the air and other negative factors but the affection is less than in the upper bands.
(SHF) Frequency band between 3 GHz and 30 GHz
Aka microwaves. Actually the microwave range includes ultra-high frequency
(UHF) (0.3-3 GHz), super high frequency (SHF) (3-30 GHz), and extremely high frequency (EHF) (30-300 GHz) signals.
Generation
Microwaves can be generated by a variety of means, generally divided into two categories: solid state devices and vacuum-tube based devices. Solid state microwave devices are based on semiconductors such as silicon or gallium arsenide, and include field-effect transistors (FET's), bipolar junction transistors (BJT's), Gunn diodes, and IMPATT diodes. Specialized versions of standard transistors have been developed for higher speed which are commonly used in microwave applications. Microwave variants of BJT's include the heterojunction bipolar transistor (HBT), and microwave variants of FET's include the MESFET, the HEMT (also known as HFET), and LDMOS transistor. Vacuum tube based devices operate on the ballistic motion of electrons in a vacuum under the influence of controlling electric or magnetic fields, and include the magnetron, klystron, traveling wave tube (TWT), and gyrotron.
Microwaves are used in bluetooth, microwave oven, radar and other applications.
High amplitude microwaves are dangerous for the health. There are real microwave weapons developed by both Russia and USA during the cold war. Psychoactive frequencies are presented within the band.
Extremely high frequency is the highest radio frequency band. EHF runs the range of frequencies from 30 to 300 gigahertz, above which electromagnetic radiation is considered to be low (or far) infrared light. This band has a wavelength of one to ten millimetres, giving it the name millimeter band.
Radio signals in this band are extremely prone to atmospheric attenuation, making them of very little use over long distances. Even over relatively short distances, rain fade is a serious problem, caused when absorption by rain reduces signal strength.
This band is commonly used in radio astronomy.
Infrared
The term "infrared" refers to a broad range of frequencies, beginning at the top end of those frequencies used for communication and extending up the the low frequency (red) end of the visible spectrum. The wavelength range is from about 1 millimeter down to 750 nm. The range adjacent to the visible spectrum is called the "near infrared" and the longer wavelength part is called "far infrared". IR radiation is assicated with vibrational energy change. If there is a chance for vibrational redistribution of electric charge (change of the dipole moment) – the molecule absorbs in certain IR frequency/ies.
Frequencies: .003 - 4 x 10exp14 Hz
Wavelengths: 1 mm - 750 nm
Quantum energies: 0.0012 - 1.65 eV
Visible Light
The narrow visible part of the electromagnetic spectrum corresponds to the wavelengths near the maximum of the Sun's radiation curve. In interactions with matter, visible light primarily acts to set elevate electrons to higher energy levels
Frequencies: 4 - 7.5 x 10exp14 Hz
Wavelengths: 750 - 400 nm
Quantum energies: 1.65 - 3.1 eV
Ultraviolet
The region just below the visible in wavelength is called the near ultraviolet. It is absorbed very strongly by most solid substances, and even absorbed appreciably by air. The shorter wavelengths reach the ionization energy for many molecules, so the far ultraviolet has some of the dangers attendent to other ionizing radiation. The tissue effects of ultraviolet include sunburn, but can have some therapeutic effects as well. The sun is a strong source of ultraviolet radiation, but atmospheric absorption eliminates most of the shorter wavelengths. The eyes are quite susceptible to damage from ultraviolet radiation. Welders must wear protective eye shields because of the uv content of welding arcs can inflame the eyes. Snow-blindness is another example of uv inflamation; the snow reflects uv while most other substances absorb it strongly.
Frequencies: 7.5 x 10exp14 - 3 x 10exp16 Hz
Wavelengths: 400 nm - 10 nm
Quantum energies: 3.1 - 124 eV
X-Rays
Are high frequency electromagnetic rays which are produced when the electrons are suddenly decelerated - these rays are called bremsstrahlung radiation, or "braking radiation". X-rays are also produced when electrons make transitions between lower atomic energy levels in heavy elements. X-rays produced in this way have have definite energies just like other line spectra from atomic electrons. They are called characteristic x-rays since they have energies determined by the atomic energy levels.
In interactions with matter, x-rays are ionizing radiation and produce physiological effects which are not observed with any exposure of non-ionizing radiation, such as the risk of mutations or cancer in tissue.
Frequencies: 3 x 10exp16 Hz upward
Wavelengths: 10 nm - > downward
Quantum energies: 124 eV -> upward
Gamma-Rays
Gamma are higly energetic rays.
In interactions with matter, gamma rays are ionizing radiation and produce physiological effects which are not observed with any exposure of non-ionizing radiation, such as the risk of mutations or cancer in tissue.
Frequencies: typically >10exp20 Hz
Wavelengths: typically < 10exp-12 m
Quantum energies: typically >1 MeV