Fundamental frequency

“ You know that heat and light are but vibrations of the ether of various frequencies, just as are radio-active or chemical rays, and the electro-magnetic waves we use for speech and signaling. Highest of all in frequency are those electro-magnetic waves ”

“ A third and constantly used expression is the term wave-frequency. If we watch a cork floating on a wave-tossed sea, we observe that it bobs up and down so many times in a minute. The number of times per second or per minute that each particle of the medium performs its cycle of motion is called the wave-frequency, or simply the frequency. ”

“ If we should gradually increase the frequency of the alternating current you would find that about sixty or perhaps a hundred cycles a second would give you the impression of a musical note. As the frequency is made still larger you have merely the impression of a higher-pitched note until we get up into the thousands of cycles a second. ”

“ As a disciple of Maxwell, et al, I am hopelessly incapable of concocting a workable theory of radiation which has nothing to do with some basic concept of frequency. Frequency, when you sit down and start analyzing it, is a nice, stable idea that explains a hell of a lot, Dusty, and as you get into atomics you find that particle radiation can be mathematically reduced to terms of frequency. ”

“ But with very high frequency impulses there is no necessity for such breaking down, since any amount of work can be performed by continually agitating the atoms in the exhausted vessel, provided the frequency is high enough. ”

“ At the red end of the spectrum the light in the neighborhood of that black line A has for its wave length 7.6; B has 6.87; D has 5.89; the "frequency" for A is 3.9 times 100 million million; the frequency of D light is 5.1 times 100 million million per second.
Now, what force is concerned in those vibrations as compared with sound at the rate of 400 vibrations per second? Suppose for a moment the same matter was to move to and fro through the same range but 400 million million times per second. The force required is as the square of the number expressing the frequency. ”

“ As these “secondary waves” return to S their distance apart is nearly equal to twice the distance between the rails, and the observer then hears a note of wave-length nearly 2EF. But if an observer is stationed at S' the waves will be about half as far apart and will reach him with nearly twice the frequency, so that he hears a note about an octave higher. As he travels further round the frequency increases still more. The railings in fact do for sound what a diffraction grating does for light.
Frequency and Pitch. ”

“ When light is analysed by a prism or grating into a spectrum, the course of each ray is deflected—refracted or diffracted—by an amount corresponding to its frequency of vibration or wave-length.
Motion of the medium, so long as it is steady, affects neither frequency nor wave-length, and accordingly is without influence on the result. ”

“ The slow fluctuations of the atmosphere are translated to a 1/f noise in the frequency domain, whose intersection with the white noise forms a knee shape. The frequency of the intersection, the knee frequency, is particularly important for ground-based experiments. ”

“ The higher frequencies give us the colors blue and green, and the lower frequencies give us the colors yellow and red. The intermediate frequencies give us the intermediate colors blue-green and orange. By vibration frequencies is meant the rate at which the ether vibrates, the number of vibrations a second. If the reader wishes to know something about these frequencies, such information can be found in a textbook on physics.
It will be found that the vibration rates of the ether are very great. It is only within a certain range of vibration frequency that sunlight affects the retina. ”

“ In using extremely high frequencies the length of the secondary--in other words, the size of the vessel--can be reduced as far as desired, and the efficiency of the light conversion is increased, provided that means are invented for efficiently obtaining such high frequencies. ”

“ Incidentally we gain, by the use of very high frequencies, many advantages, such as a higher economy in the light production, the possibility of working with one lead, the possibility of doing away with the leading-in wire, etc. ”

“ The higher the frequency, the more pronounced is this effect, hence the discharges select different paths through gaps and resistances depending upon the frequency. By frequency is meant, not the frequency of the line current but the lightning frequency, which may run into hundreds of thousands, or into millions of cycles. ”

“ Short waves, long waves, micro-waves, frequency-modulated waves, amplitude-modulated signals, every conceivable type of radiation signal, was beamed at the small, invisible, hurtling objects as they swung madly about the globe. ”

“ If the difference of frequency is not very great the two systems of waves will produce “beats”. If two broadcasting stations are transmitting on wave-lengths near together we hear a musical note or shriek resulting from the beats of the two carrier waves; the individual oscillations are too rapid to affect the ear, but they combine to give beats which are slow enough to affect the ear. In the same way the individual wave-systems in the sub-aether are composed of oscillations too rapid to affect our gross senses ”

“ As regards the currents of very high potential differences, which were employed an my experiments, I have never considered the current's strength, but the energy which the human body is capable of receiving without injury, and I have expressed this quite clearly on more than one occasion. For instance, I stated that "the higher, the frequency the greater the amount of electrical energy which may be passed through the body without serious discomfort." ”

“ Motion of the source alone crowds the waves together on the advancing side and spreads them out on the receding side. An observer therefore whom the source is approaching receives shorter waves, and one from whom the source is receding receives longer waves, than normal. At any fixed point waves will arrive, therefore, with modified frequency. ”

“ In bringing a circuit to a state of resonance by increasing the frequency, the current will increase with increasing frequency until the critical frequency is reached, and then the current will decrease in value for further increase of frequency. ”

“ Even with such trifling frequencies the energy would be practically all potential, and my conviction has grown strong that, to whatever kind of motion light may be due, it is produced by tremendous electrostatic stresses vibrating with extreme rapidity. Of all these phenomena observed with currents, or electric impulses, of high frequency, the most fascinating for an audience are certainly those which are noted in an electrostatic field acting through considerable distance, and the best an unskilled lecturer can do is to begin and finish with the exhibition of these singular effects. ”

“ So long as a source is stationary the wave-lengths emitted are quite normal, but motion of an observer may change the frequency with which they are received, in an obvious way; they are swept up faster if the receiver is approaching, they have a stern chase if it is receding. ”

“ The critical frequency of a layer depends upon the layer’s density. If a wave passes through a particular layer, it may still be refracted by a higher layer if its frequency is lower than the higher layer's critical frequency. ”

“ A thought which naturally presents itself in connection with high frequency currents, is to make use of their powerful electro-dynamic inductive action to produce light effects in a sealed glass globe. ”

“ If We know the natural frequency of vibration of the recording-index, and if by means of some mechanism we can send periodic currents of exactly the same frequency through the electro-magnet, then the intermittent magnetic pulls will exactly synchronise with the natural swings of the writing-index. ”

“ The fact that it is possible for a number of people to perceive the same noise or the same coloured pattern obviously depends upon the fact that a physical process can travel outward from a centre and retain certain of its characteristics unchanged, or very little changed. The most notable of such characteristics is frequency in a wave-motion. That, no doubt, affords a biological reason for the fact that our most delicate senses, sight and hearing, are sensitive to frequencies, which determine colour in what we see and pitch in what we hear. ”

“ It is certainly more in accordance with many phenomena observed with high frequency currents to hold that all space is pervaded with free atoms, rather than to assume that it is devoid of these, and dark and cold, for so it must be, if filled with a continuous medium, since in such there can be neither heat nor light. ”

“ You should be able to see that the effective cross-sectional area decreases as the frequency increases. Since resistance is inversely proportional to the cross-sectional area, the resistance will increase as the frequency is increased. ”

“ Accordingly, if the air offers more resistance to the high speed than to the low, the frequency of vibration in the large arcs of 180° or 160°, etc., ought to be less than in the small arcs of 10°, 8°, 4°, etc., and even less than in arcs of 2°, or 1°; but this prediction is not verified by experiment; because if two persons start to count the vibrations, the one the large, the other the small, they will discover that after counting tens and even hundreds they will not differ by a single vibration, not even by a fraction of one. ”

“ If the current be sent around a finely laminated core and a small piece of thin sheet iron be held gently against the core, a sound may be still heard with thirteen to fourteen thousand alternations per second, provided the current is sufficiently strong. A small coil, however, tightly packed between the poles of a powerful magnet, will emit a sound with the above number of alternations, and arcs may be audible with a still higher frequency. ”

“ When the potential of a body is rapidly alternated it is certain that the structure is jarred. When the potential is very high, although the vibrations may be few—say 20,000 per second—the effect upon the structure may be considerable. ”

“ Amplitude.—The largest displacement of the drop, i.e. the distance from the dotted line to C or to T, is called the amplitude of the wave. The time taken for a drop to complete one whole oscillation, i.e. the time taken for a wave to travel one whole wave-length forward, is called the period of the wave. The number of oscillations in one second, i.e. the number of wave-lengths travelled in one second, is called the frequency.
FIG. 11.
Although there is no visible displacement in the waves of light and heat, yet we may represent them in much the same way. Thus if AB, Fig. ”

“ A moment later, when they were in the tiny stateroom which Anderson facetiously called his laboratory, the scientist began: "My High Frequency Sound Projector is merely a device for producing, focussing and projecting supersonic vibrations, or waves which are similar to sound, but have enormously greater frequencies. No doubt you know that vibrations which are audible to the human ear range from 24 per second to about 40,000 per second. My device develops frequencies as high as a million vibrations per second." ”

“ If we can send out a spherical wave front, and have it lengthen rapidly as it proceeds, we will have a wave front that is, at all points, different. Any entering wave would, sooner or later, meet a wave that was half a phase out, no matter what the motion was, nor what the frequency, as long as it lies within the comparatively narrow molecular wave band. ”

“ I’ll tell you about wave lengths later. First let’s see how to control the frequency of an audion oscillator like that of Fig. 38.
It takes time to get a full-sized stream going through a coil because of the inductance of the coil. That you have learned. And also it takes time for such a current to stop completely. Therefore, if we make the inductance of the coil small, keeping the condenser the same, we shall make the time required for the current to start and stop smaller. That will mean a higher frequency for there will be more oscillations each second. ”

“ What is the form of the curve expressing the distribution of energy between the various wave-lengths in the spectrum of full radiation, or what is the distribution of heat in the spectrum? The researches of Tyndall, Draper, Langley and other investigators had shown that while the energy of radiation of each frequency increased with rise of temperature, the maximum of intensity was shifted or displaced along the spectrum in the direction of shorter wave-lengths or higher frequencies. ”

“ The surest to injure and destroy life, is a continuous current, but the most painful is an alternating current of very low frequency. The expression of these views, which are the result of long continued experiment and observation, both with steady and varying currents, is elicited by the interest which is at present taken in this subject, and by the manifestly erroneous ideas which are daily propounded in journals on this subject. ”

“ If the force expended be excessive, i.e. more than the maximum required to ensure the increased frequency proportional to the increased tension, the superfluous energy must expend itself in increasing the amplitude of the vibrations so that a note of a greater degree of loudness as well as of higher pitch will be produced. ”

“ A similar change occurs at ordinary pressures with electric impulses of very high frequency. If the molecules of the air around a wire are moderately agitated, the brush formed is reddish or violet; if the vibration is rendered sufficiently intense, the streams become white. We may accomplish this in various ways. In the experiment before shown with the two wires across the room, I have endeavored to secure the result by pushing to a high value both the frequency and potential ”