<?xml version="1.0" encoding="UTF-8"?><rss version="2.0"
	xmlns:content="http://purl.org/rss/1.0/modules/content/"
	xmlns:wfw="http://wellformedweb.org/CommentAPI/"
	xmlns:dc="http://purl.org/dc/elements/1.1/"
	xmlns:atom="http://www.w3.org/2005/Atom"
	xmlns:sy="http://purl.org/rss/1.0/modules/syndication/"
	xmlns:slash="http://purl.org/rss/1.0/modules/slash/"
	>

<channel>
	<title>frequencies &#8211; Fountain Magazine</title>
	<atom:link href="https://fountainmagazine.com/tag/frequencies/feed/" rel="self" type="application/rss+xml" />
	<link>https://fountainmagazine.com</link>
	<description></description>
	<lastBuildDate>Thu, 01 Jul 2010 00:00:00 +0000</lastBuildDate>
	<language>en-US</language>
	<sy:updatePeriod>
	hourly	</sy:updatePeriod>
	<sy:updateFrequency>
	1	</sy:updateFrequency>
	<generator>https://wordpress.org/?v=7.1</generator>
	<item>
		<title>Sounds in Nature and Journey to the Beginning</title>
		<link>https://fountainmagazine.com/all-issues/2010/issue-76-july-august-2010/sounds-in-nature-and-journey-to-the-beginning/</link>
		
		<dc:creator><![CDATA[Louima Cunningham]]></dc:creator>
		<pubDate>Thu, 01 Jul 2010 00:00:00 +0000</pubDate>
				<category><![CDATA[Issue 76 (July - August 2010)]]></category>
		<category><![CDATA[autonomic]]></category>
		<category><![CDATA[body]]></category>
		<category><![CDATA[brain]]></category>
		<category><![CDATA[clutch]]></category>
		<category><![CDATA[energy]]></category>
		<category><![CDATA[frequencies]]></category>
		<category><![CDATA[heart]]></category>
		<category><![CDATA[Matter & Beyond]]></category>
		<category><![CDATA[music]]></category>
		<category><![CDATA[nature]]></category>
		<category><![CDATA[nervous]]></category>
		<category><![CDATA[normal]]></category>
		<category><![CDATA[response]]></category>
		<category><![CDATA[sound]]></category>
		<category><![CDATA[sounds]]></category>
		<category><![CDATA[stress]]></category>
		<category><![CDATA[sympathetic]]></category>
		<category><![CDATA[system]]></category>
		<category><![CDATA[table]]></category>
		<category><![CDATA[time]]></category>
		<guid isPermaLink="false">http://107.21.79.195/all-issues/2010/issue-76-july-august-2010/sounds-in-nature-and-journey-to-the-beginning/</guid>

					<description><![CDATA[If we seek solace and peace in the sounds of nature and in our houses of worship, what happens to us the rest of the time when we are bombarded by sound at every turn? It seems like no matter where we are these days, it is impossible to escape the sound of traffic, sirens, [&#8230;]]]></description>
										<content:encoded><![CDATA[<p>If we seek solace and peace in the sounds of nature and in our houses of worship, what happens to us the rest of the time when we are bombarded by sound at every turn? It seems like no matter where we are these days, it is impossible to escape the sound of traffic, sirens, the phone ringing… just the din of everyday life, which has become louder and more pervasive than ever. How is this new world of ceaseless sound affecting our bodies and our minds?</p>
<p><span id="more-1149"></span></p>
<p>We invite you to embark on a journey with us to explore some fascinating perspectives that shed a light on our relationship with sound and music.</p>
<p>Dr. Jeffrey Thompson, the Founder and Director of the Center for Neuroacoustic Research in California (www.neuroacoustic.com), is recognized as a worldwide expert in the field of acoustic pacing frequencies that are incorporated into musical sound tracks. A consummate musician and composer in his own right, he has established a method for using modulated sound-pulses that change states of consciousness for optimal “Mind-Body” healing. Dr. Thompson believes that the sounds in nature resonate with us because they take us back to the beginning of our journey and our primary senses.</p>
<p><b>Matter&amp;Beyond: </b> Why are sound and music so central for us, both culturally and personally?</p>
<p>I don’t think I’ve found a single culture on earth which at some point hasn’t used sound as a prominent technique in healing, in religious rites, or as a means of attaining a change of consciousness in one way or another. I think the tradition probably dates back to the first use of sound as a soothing or healing means for mothers; that is lullabies for babies.</p>
<p><b>M&amp;B: </b> Is this our earliest experience with sound? Is this what you call primordial sounds?</p>
<p>If you go back to before the lullabies, we’re talking about womb experiences and it’s one of the primal things we all share; this is what I call primordial sounds. Certain type of sounds have the same influence on anyone who hears it, no matter what age you are, what sex you are, what culture you were brought up in, what language you speak; womb sounds fit that criteria.</p>
<p><b>M&amp;B: </b> Why is it sound, but not the vision?</p>
<p>Because at 16 weeks, when the fetus is very small, the nervous system is developed enough that all the senses are functioning; however it is dark, so the eyes aren’t working, no information is being received and the nose and the mouth are filled with fluids, so there is no tasting or smelling, but sound travels through water five times better than it does through air; therefore the ears are working but amplified by five times, and the largest sense organ we have, the skin, is a huge sense organ for vibrations. Thus, we’re experiencing vibration and sound for nine months in the womb and that sound environment is a very specific type of environment; the amniotic fluid sounds, the watery bubbly sounds, the mother’s heartbeat through the placental artery, respiratory sounds from the diaphragm, noises of the internal organ; it’s a rich complex, three-dimensional sound environment that is exactly the same for everyone of us; we all experienced this in the same way.</p>
<p><b>M&amp;B: </b> How does the fetus perceive this sound?</p>
<p>Remember the fetus is small and the ear is small; the eardrum is extremely small. If the eardrum was blown up to the size of my eardrum and the mother’s heart was blown up in proportion it would fill this room. So what kind of sound would such a heart make? It wouldn’t be the sound that you would expect it to be listening to the adult’s heart with a stethoscope from the outside; it would be a very large, slow sound, a large thumping sound.</p>
<p><b>M&amp;B: </b> How is this related to the use of sound in therapy or for relaxation?</p>
<p>Most of us who have gone on vacations and have explored nature feel a peaceful, beautiful return to nature; why?</p>
<p>Because if you take the sounds of the amniotic fluid and you slow those sounds down, they sound a lot like the ocean. The size of the sound waves compared to the eardrum would make these watery sounds sound like they have also slowed down. So many of the watery sounds in the womb sound like other sounds that we can hear later in nature. This can spark a similar kind of primordial recognition which is beyond the control of the rational thinking mind.</p>
<p>So when we build up these kinds of sounds on a soundtrack you can then push the button and the body will automatically go back to what it felt like to have a natural experience; when we combine the sounds of nature with music this makes a relaxation tape. So I would say that the sounds of nature provide secondary primordial sounds, as not all of us would have heard the same natural sounds in our lives.</p>
<p>The idea is to extend the power of the primordial recognizable components of sound in order to create a physical response. The technique is to connect with a primal recognition at a subconscious level; this will tap into experiences that you have had in the womb and at other times.</p>
<p><b>M&amp;B: </b> You not only use sound for relaxation, but also in order to combat stress. Could you please talk about this?</p>
<p>When a person has a fight-or-flight response, a stress response, we know very precisely what happens physiologically. The very first thing, the most sensitive organ, to respond to stress is the heart and thus when we look at the heart waves we can gain important information.</p>
<p><b>M&amp;B: </b> Why the heart and not the brain?</p>
<p>The reason for this is that the heart is the perfect system in the nervous system; it is called the autonomic nervous system or the automatic functioning nervous system; it knows how to organize and control my organs and glands and body chemistry and perform biomechanics that I’m not aware of and can’t control.</p>
<p>My rational-thinking brain can control physical body movements and thinking processes, but there’s another section that controls the automatic functioning of how my body runs. There is another control of this autonomic nervous system, which has two large branches of nerves that innervate all the organs and glands; these two branches of the nerves are the sympathetic and the parasympathetic nervous system.</p>
<p>While the sympathetic nervous system switches on, the parasympathetic switches off and mobilizes energy from the higher brain centers, from my digestive system, from my elimination system and from my immune system, it pulls that energy into my muscles to fight for my life.</p>
<p>This is when the brain freezes when you take an exam. You’re frightened about the exam; it is your final exam and you’re frightened that you’re not going to pass it or that you’re not going to do well. That fright causes the sympathetic system to switch on and drain the energy out of your brain; this is a self-fulfilling prophecy. You don’t have a brain left, because all the energy has gone to your muscles. At the moment the sympathetic system switches on, it mobilizes the pituitary which signals the adrenal glands; these fires adrenaline, the adrenaline starts the heart and the respiration and a number of other things. At the same time it suppresses the pancreas and lets loose extra glucose so you can fight for your life more and so what you end up with is the very first thing that happens.</p>
<p><b>M&amp;B: </b> What is the normal stress response and how do we return to a normal state?</p>
<p>When a person is required to carry out special tasks, like running or fighting for one’s life, then the sympathetic nervous system has to switch on, mobilize the energy from various places and send it to my muscles. If I am injured, but I survive and win, then the parasympathetic system is going to switch on and build up; that energy will be sent to my immune system, healing centers and recuperation areas for my muscles; when this is finished these are basically switched off, because we don’t need this energy anymore. This is certainly the normal way of functioning.</p>
<p>Thus, there are certain normal ways in which the body should function when a person is okay and normal. When the patient comes in and lies down on their back we hook them up and look at what’s happening in the autonomic nervous system. Normally when you lay down for three to five minutes your system should relax. Gravity isn’t affecting you, your heart doesn’t have to do extra work to pump the blood up to your brain; as a result the muscles relax and the sympathetic system and parasympathetic nervous systems should be at a level playing field. Now they can conserve their energy and this state of balance in the autonomic nervous system is known as homeostasis. The best state of health you can have is in homeostasis, where you’re not using energy in an unnecessary way. Homeo means unity, one, within my body, while stasis is a perfect state of rest.</p>
<p><b>M&amp;B: </b> What are the results of your studies to date? How many of us return back to homeostasis in three to five minutes?</p>
<p>Clinically what I see is maybe two patients with a normal response; I’ve been checking every patient with the real time heart rate variability system now for 7 years. This means thousands of patients; in all of that time I have seen one, maybe two patients with a normal response. I hook the patient up, and see what the response is. Most people’s response is abnormal; what this abnormality says is that after five minutes they have not attained a balance, and they have a good strong, healthy, dominant sympathetic stress response which never stops.</p>
<p><b>M&amp;B: </b> What do you think is the reason for this?</p>
<p>This state is constant because of the artificial, extremely stressful world that we have artificially created for ourselves. It wasn’t supposed to be like this; you are supposed to wake up in the morning and grab your spear and go catch a rabbit and that’s your workday; when you get there and you see that rabbit the sympathetic system turns on and the heart rates increase, the same thing happens with the rabbit, and it’s all going to be over in a couple of minutes. You’re going to catch the rabbit or he’s going to get away and then everything goes back, the clutch pushes in. Let’s say you get the rabbit, and the clutch pushes in; everything is fine and you are going to go home. Now you hear a growl behind you and there’s a saber tooth tiger looking at you, thinking about dinner; now the sympathetic system switches on, the heart rate is up, and you are running and he is running. It is all going to be over in a couple of minutes and either you are going to get away or you’re not.</p>
<p>But what I’m talking about here is that the nervous system, at its core, and its stress response are both designed for a sprint and not a marathon; but what we have had in the twenty-first century and throughout the twentieth century is a marathon of stress; but these are the kind of stresses that we can’t see, i.e. invisible stresses. They’re electromagnetic frequencies; the walls in this room, television channel frequencies, military frequencies, microwave frequencies, air pollution, food pollution and traffic jams when going to work to a job that doesn’t pay enough money for a boss who has the emotional development of a three-year old are all problems for us. The stress goes and then it’s back again; it’s time to get dinner for the kids and watching 7:00 news. This doesn’t stop; the nervous system’s solution to surviving this is to invent a mechanism of merely stepping on the gas, switching on the emergency sympathetic system on and bulldozing your way through the stress for the rest of your life with great momentum; but at nighttime, when it’s time to go to bed the nervous system doesn’t want to let go of this momentum that it has built up to get through the day.</p>
<p><b>M&amp;B: </b> And this has devastating effects on our health?</p>
<p>You can’t keep running in high gear for the rest of your life without some horrible consequences; the body’s not designed for it. You can only do this for a few decades before your heart or your brain blows up, the two biggest killers in Western society are heart attacks and strokes – there is also high blood pressure and diabetes. But what can we expect if our sympathetic nervous system is all the time working, which means by definition that our heart pressure is up and the pancreas is suppressed, so there is extra glucose being sent out? So people who don’t have the constitution to handle the stress blow a fuse; they have no way to handle the stress and as a result they have immune system problems, digestive problems, and problems that come from that colon cancer, irritable bowel syndrome, autoimmune diseases, allergies.</p>
<p><b>M&amp;B: </b> You are using sound in order to help people return to their normal healthy state. How does this work?</p>
<p>I’ve come up with a way to use sound to force the autonomic nervous system to push in the clutch, removing us from a place of high stress from which you can leave by using sound; we do this by using the heart-rate variability to see how bad the heart rate is and then explore various precisely tuned sound frequencies which will actually force the nervous system to push in the clutch. There will be a very specific tone for every person; this is like a glass vibrating if I sing the right note. An opera singer can sing the right note to make the glass vibrate. Well, now let’s imagine that your autonomic nervous system is the glass and we’re going to explore various sound frequencies that are very precisely tuned to find out which one affects your autonomic nervous system function; when we find it the response will be like pushing in the clutch and sending it into a state of relaxation. So we hit the right note and we get the response; this is what I’ve been looking for. Now we can see this phenomenon clinically. Once we’ve got the tone that’s associated with the pushing in of the clutch of the autonomic nervous system we can use that therapeutically through a specially designed sound table that I have made; this consists of low-frequency sound components which drive the low frequencies right into your cells via headphones. This relaxation mode is introduced to your nervous system over an extended period of time. We can burn this sound onto a CD and you can take it home and work with it at home on your stereo; it is like an internal training program. Every time your nervous system pushes in the clutch, the ability to push in the clutch grows, just like working a muscle in a gym.</p>
<p>This is a kind of high-tech stress reduction training program for the nervous system with sound. This is one of the three components I mentioned earlier; there are three parallel processes using sound for healing. This one is the idea of using the physical resonance to cause an effect on the nervous system to relax people.</p>
<p><b>M&amp;B: </b> This is what is called a sound table, right?</p>
<p>Yes, the sound table I needed had to have specific requirements, which is why I had to make my own to attain the exact clinical results I wanted. The power in the table actually delivered more power to your body than I wanted to be delivered. Therefore, I had to be able to have the sound that was coming from the table split into the right and left speakers, but none of those that were available on the market could do that. So I had to have it specially designed. As a composer, musician and audio engineer I was able to design the sounding board of that table and the transducers so that a lot of free sound could be delivered and spread out, therefore it is much more effective and delivers the sound to your body via headphones. Thus there is a lot going on in that table that you cannot see and this is what makes it work properly.</p>
<p><em>Interview conducted by Mustafa Tabanli for Ebru TV for the Emmy Award winning television series Matter and Beyond.</em></p>
]]></content:encoded>
					
		
		
			</item>
		<item>
		<title>Radar-Evading Moths</title>
		<link>https://fountainmagazine.com/all-issues/2008/issue-64-july-august-2008/radar-evading-moths/</link>
		
		<dc:creator><![CDATA[Louima Cunningham]]></dc:creator>
		<pubDate>Tue, 01 Jul 2008 00:00:00 +0000</pubDate>
				<category><![CDATA[Issue 64 (July - August 2008)]]></category>
		<category><![CDATA[balance]]></category>
		<category><![CDATA[bats]]></category>
		<category><![CDATA[creatures]]></category>
		<category><![CDATA[equipped]]></category>
		<category><![CDATA[food]]></category>
		<category><![CDATA[frequencies]]></category>
		<category><![CDATA[insects]]></category>
		<category><![CDATA[larvae]]></category>
		<category><![CDATA[moth]]></category>
		<category><![CDATA[moths]]></category>
		<category><![CDATA[nature]]></category>
		<category><![CDATA[organs]]></category>
		<category><![CDATA[perfect]]></category>
		<category><![CDATA[plants]]></category>
		<category><![CDATA[produce]]></category>
		<category><![CDATA[Science]]></category>
		<category><![CDATA[sound]]></category>
		<category><![CDATA[sounds]]></category>
		<category><![CDATA[species]]></category>
		<category><![CDATA[tympanal]]></category>
		<guid isPermaLink="false">http://107.21.79.195/all-issues/2008/issue-64-july-august-2008/radar-evading-moths/</guid>

					<description><![CDATA[Members of the animal kingdom are equipped with amazing features. Every species has a particular gift for communication, feeding, or defense. They communicate through various means, such as smell, vibration, sound, light, and heat. For example, fireflies use light for communication and ants use different smells, whereas crickets or grasshoppers use sound. Certain insects which [&#8230;]]]></description>
										<content:encoded><![CDATA[<p>Members of the animal kingdom are equipped with amazing features. Every species has a particular gift for communication, feeding, or defense. They communicate through various means, such as smell, vibration, sound, light, and heat. For example, fireflies use light for communication and ants use different smells, whereas crickets or grasshoppers use sound. Certain insects which have no separate organs to produce sound just flap their wings or vibrate certain parts of their body to communicate. Receiving these messages is no less important than sending them, since the capacity to perceive the sound waves in the environment is an important aspect of defense against enemies. Insects use sensor hairs that are distributed over different parts of their body to receive sounds produced by their fellow insects or other animals. These organelles are made up of a hair and sensor cell, and they are usually located in groups. The vibrations detected in the environment are transmitted to the relevant neurons. Afterwards, a responsive signal is produced according to the sound received. In addition to these hairs, certain insects have been equipped with a pair of more complex (tympanal) hearing organs. The frequency of the sounds they can receive depends on the environmental conditions and the species of the insect. For example, crickets can hear within a frequency range that is very close to that of human ear (100-15,000 Hz), and grasshoppers can hear sounds of far higher frequencies (100-100,000 Hz).</p>
<p><span id="more-929"></span></p>
<p>There is no similarity between the systems through which insects produce or receive sounds. Furthermore, even the frequencies of the sounds they produce or hear may not be the same. The wisdom behind this might be that the receptors of some insects are devised in a way that will enable them to detect sounds produced by their enemies. Moths can be given as a typical example of this. They can detect sounds between 1,000-140,000 Hz. Their sensitivity is best between frequencies of 20,000-40,000 Hz, but interestingly, most moths do not have any organs to produce sounds at these frequencies. In other words, moths do not seem to use their tympanal organs in order to communicate with one another. Discovering the real function of the tympanal organ of the moths has taken researchers quite a long time.</p>
<h3><b>The mysterious relation</b></h3>
<p>Every being in nature is created to assume a role in the ecological balance and no creature has been equipped with a useless organ. Researchers have discovered that the tympanal organ plays an important role in defense. Moths spend the day resting in corners and only become active after sunset. Researchers have come to the conclusion that they are not searching for food, since the nutrition they need is stored in their bodies during the larva stage. Thanks to this blessing, moths do not spend their short life span in search of food. The aim of their night flights is reproduction.</p>
<p>The essential duty of moths is to find the plants where they will lay their eggs and on which their larvae will feed. As slow moving animals, it is almost impossible for the moth larvae to go and find their own food. As all creatures are provided in accordance with their need, these helpless larvae are born on their food. Another amazing fact about their nutrition is that the moth larvae eat their own protein-rich eggshells before eating leaves. Research has shown that those larvae which eat their eggshells are more resistant to environmental conditions.</p>
<p>As the moths try to continue their species by laying their eggs in the darkness, some other creatures try to continue their own existence by feeding on the moths. Bats eat insects and are also active at night. As is well known, bats fly comfortably in the dark thanks to the radar system they have been equipped with. This innate system is perfectly devised to enable bats to pinpoint a tiny insect flying through the darkness, and moths are a prey that is easily spotted by bats. The astonishing fact is that the moths’ sensitivity to the sound waves is perfect for picking up the sounds emitted by bats. The moths are able not only to detect the bats, but also to judge their distance from the frequency of the waves. If the distance is greater than 30 meters, the moth leaves the area immediately. If the bat is closer however, the moth takes a zigzag course or tries to avoid danger by plunging down and staying still.</p>
<p>The balance here is so perfect that while bats are skilled enough hunters to obtain provision, the moths are good defenders and are able to continue their existence. Both species fulfill their roles in balance with creation. Some bats are able to catch some moths, but there is no excess on either side. Nothing is left to blind chance in nature; not only did the Creator equip the bat with a perfect radar system, He did not leave the moth helpless but granted them perfect receptors to rescue themselves from bats. If it were not for the Power that established the mysterious balances in the universe, how would a bat find its way through the darkness and how would moths be protected from extinction?</p>
<p>Every different type of moth which forms another ring in the chain of food in nature lays its eggs on different plants. If moths did not feed on certain fast-growing plants and if their growth is not kept under control, these plants would invade the space of other plants and wipe them out. The moths and other creatures that feed on plants ensure that no one plant is allowed to upset the balance of the chain of nutrition. Similarly, the perfect balance established between bats and moths prove that nothing in this universe is left on its own. When confronted by the perfect order in nature, one cannot help but think about the verse:</p>
<p>You do not see any fault or incongruity in the creation of the All-Merciful. Look yet again: can you see any rifts?</p>
<blockquote>
<p>Then look again and yet again, (and however often you do so, with whatever instruments to aid your looking) your sight will fall back to you dazzled (by the splendor of God’s creation), and awed and weakened (being unable to discern any flaw to support any excuse for claiming that there could be any sharing in the dominion of the universe). (Mulk 67:3)</p>
</blockquote>
]]></content:encoded>
					
		
		
			</item>
		<item>
		<title>The Importance of Ionosphere in Radio Communication</title>
		<link>https://fountainmagazine.com/all-issues/2006/issue-55-july-september-2006/the-importance-of-ionosphere-in-radio-communication/</link>
		
		<dc:creator><![CDATA[Louima Cunningham]]></dc:creator>
		<pubDate>Sat, 01 Jul 2006 00:00:00 +0000</pubDate>
				<category><![CDATA[Issue 55 (July - September 2006)]]></category>
		<category><![CDATA[communication]]></category>
		<category><![CDATA[earth]]></category>
		<category><![CDATA[frequencies]]></category>
		<category><![CDATA[frequency]]></category>
		<category><![CDATA[high]]></category>
		<category><![CDATA[ionization]]></category>
		<category><![CDATA[ionosphere]]></category>
		<category><![CDATA[ionospheric]]></category>
		<category><![CDATA[layer]]></category>
		<category><![CDATA[layers]]></category>
		<category><![CDATA[long]]></category>
		<category><![CDATA[propagation]]></category>
		<category><![CDATA[radio]]></category>
		<category><![CDATA[Radio waves]]></category>
		<category><![CDATA[reflected]]></category>
		<category><![CDATA[Science]]></category>
		<category><![CDATA[solar]]></category>
		<category><![CDATA[space]]></category>
		<category><![CDATA[sun]]></category>
		<category><![CDATA[waves]]></category>
		<guid isPermaLink="false">http://107.21.79.195/all-issues/2006/issue-55-july-september-2006/the-importance-of-ionosphere-in-radio-communication/</guid>

					<description><![CDATA[The first step in using electromagnetic waves in space for radio communication was taken by James Clark Maxwell when he came up with “the theory of the electromagnetic field” in 1873. Maxwell claimed that magnetic waves were subject to reflection, refraction, and absorption, just as light is. The existence of these waves was first demonstrated [&#8230;]]]></description>
										<content:encoded><![CDATA[<p>The first step in using electromagnetic waves in space for radio communication was taken by James Clark Maxwell when he came up with “the theory of the electromagnetic field” in 1873. Maxwell claimed that magnetic waves were subject to reflection, refraction, and absorption, just as light is. The existence of these waves was first demonstrated by Heinrich Rudolph Hertz in some experiments carried out in 1888. His studies constituted the base for Guglielmo Marconi to conduct experiments with wireless telegraphy using Morse code.</p>
<p>In 1896, Marconi was successful in sending signals through a wireless telegraph to a distance of a few kilometers away. However, how would it be possible to provide intercontinental communication via radiotelegraphy and radiotelephone? In 1901, together with his assistants, G.S. Kemp and P.W. Paget, Marconi successfully transmitted and received transatlantic signals between Poldhu, Cornwall and New Foundland, Canada, using a kite aerial at Signal Hill in Cornwall, England. It was Edward Appleton who first discovered that radio waves were broadcast around the world after they are reflected back from the ionosphere, one of the highest electrified layers of the atmosphere that contains large concentrations of charged particles (ions) and free electrons. Electromagnetic waves that are sent from radio transmitters to outer space are reflected back to every corner of the Earth after hitting this gas and plasma layer that is composed of charged particles. Thus, radio and radiotelephone communication is made possible for the benefit of human beings. After that time, being able to use a law that had been ordained by the Supreme Creator, human beings were able to reach a level that enabled them to conduct transatlantic communications via radiotelegraphy. But what makes radio waves so special?</p>
<h3><b>Radio waves</b></h3>
<p>The frequency spectrum of electromagnetic waves begins from the “sub-sound frequency region” (1Hz) stretching up until cosmic rays (Figure 1). Radio communication is made using the electromagnetic waves that form part of this frequency spectrum. Radio communication systems can be classified into four groups relating to their frequency regions:</p>
<p>&#8211; LF/MF (Low Frequency/Medium Frequency)</p>
<p>&#8211; HF (High Frequency)</p>
<p>&#8211; VHF/UHF (Very /Ultra High Frequency)</p>
<p>&#8211; SHF (Super High Frequency)</p>
<p>Specifications of radio waves are taken into account in this classification. The main element that makes radio waves similar or different from each other is the frequency band that determines their wave length. Radio waves move at the speed of light (300 thousand km per second), much faster than sound itself, so to find the wave length of a radio wave, we divide its velocity by its frequency.</p>
<p>Frequencies used within the radio frequency spectrum measure between 20 KHz and 30 GHz. Theoretically, the high frequency band is between 3 and 30 MHz, while in practice it is between 1.6 and 30 MHz. The interval between 4 and 18 MHz is the most-widely used region in the spectrum.</p>
<h3><b>The atmosphere</b></h3>
<p>Our Lord, Who incessantly prepares the Earth in a beautiful manner, also protects all of life with a perfect shield called the “atmosphere.” Scientists have divided the atmosphere into seven layers in order to reveal the unknown facts about it. These seven layers are different from each other in terms of temperature, pressure and humidity levels, and the natural events that occur in them. If we ascend from the Earth toward the sky, we pass through the layers of the troposphere, stratosphere, ozonosphere, mesosphere, thermosphere, ionosphere and the exosphere. All these layers cover a distance of about 3,000 km. Each of the atmospheric layers serves a vital cause. Every layer has many functions, ranging from the formation of rain clouds to the prevention of harmful beams reaching the Earth, from reflecting radio waves to inactivating meteors. One duty of the ionosphere that we are aware of today is to act as a reflector and distributor for radio waves.</p>
<h3><b>The ionosphere and distribution of radio waves </b></h3>
<p>Good transatlantic radio communication depends upon many factors. Depending on the frequency of the radio waves, the season of the year, the position of the Sun, the location of the broadcasting area and the time of day, the communication area may vary from 100 km to 10,000 km.</p>
<p>Radio waves are propagated around the Earth in two forms, either as ground waves or as sky waves (Figure 2). In high-frequency radio communication, it is important to choose the best frequency for the time and means of propagation.</p>
<p>Starting from 50 km above the Earth and stretching 440 km, the ionosphere is filled with a high concentration of free electrons and gases. Why is the ionosphere important for transatlantic radio communication? The electrified ions that fill the whole of the ionospheric layer that completely surrounds the Earth reflect radio waves from all directions to every part of the world. According to their frequencies and ionization, radio waves are completely absorbed in the ionosphere and they are either partly refracted and distributed to the outer space or are reflected and returned to the world. The electromagnetic waves within a range of 30 MHz can return to Earth after being reflected by the ionosphere.</p>
<p>It is accepted that the ionosphere is formed at different ionizing levels in different layers, known as D, E, F1, and F2 (Figure 3). The ionization level in the outer layers of the ionosphere is higher than that of the inner layers. The D layer, the innermost layer of the ionosphere, is 76-93 km above the Earth and is characterized by low ion densities and low collision frequencies of electrons and ions with neutral particles. Serving to absorb most energy below 7 MHz, this layer is ionized during the daylight hours, completely disappearing at night. It reaches full ionization level just after sunrise and is at its peak at noon time, immediately losing energy after sun-set.</p>
<p>The E layer is the region of the ionosphere that was discovered first. In this layer, molecular ion production is at its peak at about 110-115 km above the Earth. There are plenty of molecular gases at this height. This layer is a suitable platform from which radio operators can reflect signals to distant stations. Reaching a maximum at noon, the ionization in the E layer decreases towards the end of the day, disappearing completely at midnight. Moreover, at unpredictable intervals, ionized gas clouds accumulate in certain regions of this layer. This can be detected by the variable dense clouds of ionization that occur in the E layer due to the spatial and temporal structure in the ionizing particle precipitation. The plasma density of the E layer can be greatly changed because of these occasional formations. These formations, which are called “sporadic E layers,” are used by radio amateurs for long distance VHF (Very High Frequency) operation. Since the plasma density in layers D and E is highest at noon and present during the other hours of daylight, these layers are used in the daytime.</p>
<p>The next layer of ionosphere exists at about 160 and 400 km above the Earth and consists of layers that have a higher density of free electrons caused by the ionizing effect of solar radiation. Since the density of gas molecules at this height is low, ion and electron collisions occur very slowly in this layer. When solar radiation is high (during the day) this layer can be divided into two independent regions, F1 and F2. The F1 layer is present at 152 and 203 km above the surface of the Earth. During the night, the F1 layer merges with the F2 layer. The F2 layer exists at 250 and 400 km above the surface of the Earth. The majority of HF (shortwave) transmissions are propagated by the F2 layer, which is the main reflecting layer for HF communications both at day and at night. Reaching its maximum level of ionization just after midday, the layer is at its minimum just before sunrise. The F2 layer can be used for 10-20 MHz during the day and 3-8 MHz during the night. Since the F layer exists at a very high altitude, it is exposed to sunlight for longer periods of the day and it dissipates very slowly at night. In this case, the only layer of the ionosphere that can be used during the night is the F layer, which I is composed of the F1 and F2 layers.</p>
<p>Solar radiation, and consequently ionization, alters periodically. For instance, as the days are long during the summer months, ionization is also high at this period. During this time, radio waves are absorbed or attenuated more in layers E and D, and propagation covers only a small area. However, since the days are shorter during the autumn and winter, less solar energy reaches these ionospheric layers. Hence, low frequencies can easily pass through the weakly ionized D and E layers and reach the stronger F layer from where they can be propagated over long distances.</p>
<p>Another long term factor in ionization is the regular 11-year activity cycle of sun spots. Sun spots are believed to be caused by violent eruptions on the Sun and they are characterized by unusually strong magnetic fields. During periods of maximum sun spot activity, the density of ionization increases in all the layers of the ionosphere. During these periods, the D layer absorbs more and the critical frequencies of layers E, F1 and F2 are higher, therefore, for long distance communication higher operating frequencies over 30 MHz should be used. During terms of minimum sun spot activity, the E and F layers have weak ionization, so they cannot reflect the radio waves back onto the Earth. In this period, frequencies over 20 MHz are not used much. Along with this regular variation, “sudden ionospheric disturbances (SID)” also negatively affect the propagation of radio waves. SID are thought to be caused by severe solar eruptions, but the real cause of this phenomena is still not clearly known. (Figure 4)</p>
<p>Sudden ionospheric disturbances can disturb radio communication for hours or even days. Strong solar eruptions cause a sudden abnormal increase in the ionization density in the D layer, hence even the high frequency radio waves coming from the side of the Earth that is facing the Sun are completely absorbed by this layer and frequencies above 2 MHz are unable to penetrate it. When SID occurs, long distance propagation of HF radio waves may be completely blocked.</p>
<p>Ionospheric storms are another disturbing factor for radio communication. When a solar eruption occurs, it takes between 20 and 40 hours for the magnetic storm to reach the Earth. The ionospheric storms cause the F2 layer to virtually lose its ion density. At this time, when the range of frequencies used for communication is much smaller than normal, communication is only possible at lower frequencies.</p>
<h3><b>Frequency and propagation routes in radio communications</b></h3>
<p>The definition of the frequency to be used for radio communication is an important parameter for ensuring healthy propagation. For this, the Maximum Usable Frequency (MUF), and the Lowest Usable Frequency (LUF) are determined. Frequencies over MUF penetrate the ionosphere, shooting right through the ionosphere and going out into space, whereas frequencies below MUF are reflected. LUF is the lowest frequency that is completely absorbed in the D layer. To conduct good communication, a frequency, calculated as MUFÃ—0.85, should be used. This frequency may be lower at night and higher during the day.</p>
<p>Apart from the propagation frequency, the path that is chosen to transmit the radio waves from one point to the other also must be calculated accurately. The angle at which the radio waves enter the atmosphere (angle of incidence) defines the path that will be covered by the waves on their way to Earth. The angle of incidence should be small enough for the waves to be reflected back to Earth and large enough so that the waves will not penetrate the ionospheric layer. Smaller critical angles should be used for smaller frequencies and larger critical angles should be used for larger frequencies so that they will not penetrate through the ionospheric layer and be lost in space.</p>
<p>Consequently, apart from periods when solar eruptions are strong, radio waves that are over 30 MHz frequency are not reflected and can penetrate the atmosphere and reach outer space, hence making the communication between outer space and the Earth possible.</p>
<p>For transatlantic communications conducted via communication satellites, radio waves over 30 MHz are used. Artificial satellites imitate the ionospheric layer, their original source of inspiration, and act as a reflector for these waves (Figure 5). Waves coming from the Earth are reflected by these satellites if they are within their coverage area. However, these manmade satellites have very limited coverage areas. Although they are produced with the highest technology available, their cost is very high and they last only for about 25 years. Nevertheless, for radio waves lower than 30 MHz, the ionosphere, that covers the whole of our planet, acts as a natural satellite. Because of this characteristic of the ionosphere, we do not have to focus at any certain point. Moreover, there is no need for maintenance, nor any energy supplement, and the ionosphere is permanent. The atmosphere has been granted for our service for as long as Earth survives. Through searching and exploring new facts about the universe and all beings, we realize more and more that neither meaningless nor useless matter exists in the material world of creation. Therefore, we are better able to understand that the universe is packed with wonderful favors and blessings that are addressed directly to humanity.</p>
]]></content:encoded>
					
		
		
			</item>
	</channel>
</rss>
