Preface to the lecture, 1

Scalar wave technology in antiquity 

623

 

30.8 Modulation of acoustic signals 

In the case of sound it in essence concerns longitudinal waves, which propagate in all 

directions in space with the velocity of sound. But this merely is an average velocity, since 

the air molecules strictly speaking oscillate with the sound frequency in the direction of 

propagation. In this way the velocity of sound one time is increased and the next moment 

to the corresponding extent reduced. If the molecules already carry out oscillations of 

themselves, e.g. thermal motion, then both oscillations overlap; i.e. the motion of itself is 

modulated with the sound frequency.

 

Following the here presented derivation potential vortices are formed in every dielectric, 

thus also in air, and these are modulated if overlapped with sound waves. Vortices 

however do not form a distinct frequency, but entirely on the contrary a uniform frequency 

mixture in the form of white noise.

 

The overlap thus also is noise unless certain noise frequencies are favoured. This can be 

effected by means of a spatial body tuned to a certain wavelength. To be considered are 

cuboid cavities, as in the case of Greek temples or waveguides and cylindrical objects as 

in the case of round temples or magnetrons. The building form causes the favouring of a 

certain frequency and the integer harmonic frequencies belonging to it. 

If this frequency now lies in the high frequency range, then it is emitted by the spatial 

body as an electromagnetic wave, in the case of waveguides and resonant circuits for 

reason of the small dimensions as microwave radiation and in the case of the Greek 

temples as short wave radiation. If one in addition produces an acoustic signal in the 

frequency determining spatial body, then this signal automatically will modulate the high- 

frequency signal.

 

The result of the modulation is the overlapping of the sound wave with the high-frequency 

carrier wave. The change of the active length, thus the wavelength of the HF-carrier 

causes a change of frequency. Such a change on the beat of the sound frequency is called 

FM (frequency modulation). For that we imagine a spatial body being excited because of 

its length by potential vortices to a high-frequency oscillation at the self-resonant 

frequency.

 

From flow dynamics is known, how easy the distribution of vortices in space can be 

disturbed. Already words spoken in space are able to influence the potential vortices, 

which in the case of the temples were used as energy carrier. The longitudinal sound 

waves reflected at and thus returning from the Cella wall rigid for sound of a Greek temple 

will push these potential vortices back on the beat of the sound and with that shorten the 

active length. This means, that the carrier frequency is modulated with the sound 

frequency. The carrier oscillation thus permanently changes its phase on the beat of the 

sound signal, for which reason this particular kind of modulation is described as PM, as 

phase modulation.

 

Nowadays PM is used only seldom and in the SW-range not at all because of the big need 

of wave bandwidth. Merely at higher frequencies PM occasionally is used in 

radiotelephony. In the case of the frequency modulation usual in broadcasting (e.g. UHF), 

the change of frequency takes place on the beat of the sound amplitude and not of the 

sound frequency as with PM. Therefore it is not possible to receive phase modulated 

signals, which are produced by means of the acoustic coupling of appropriately formed 

spatial bodies

 with commercial FM receivers.

 

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Broadband FM broadcasting technology

 

 

Fig. 30.9:         The Pantheon in Rome, the ,,temple of all 

gods".

 

Diameter D = 43,2 m, Golden Proportion: = 0.618 

Pronaon-(atrium-)length:

= 0.618 • 43.2 = 26.7 m 

Built under emperor Hadrian 118/ 119-125/128 A.D.

 

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Scalar wave technology in antiquity ______________________________________ 625

 

30.9 Broadband FM broadcasting technology

 

If I speak against a flat wall, then every point on the wall has another distance to my 

mouth. The sound waves thus aren't reflected simultaneously, what leads to big 

modulation distortions. Therefore the sound wall should be curved in such a way, that all 

signal paths are the same length (barrel vault, apse, etc.). In the case of point sound 

sources there results as an optimum a hemisphere, for instance a dome. The building hence 

even today tells us, which frequency and which modulation method had been put to use. 

The architecture of sacral buildings, e.g. pointed arch or round arch, thus hardly has been a 

question of aesthetics.

 

For his temple of Venus and Roma designed by himself emperor Hadrian had to listen to 

severe criticism among others of Apollodor of Damascus. The temple was too broadband 

for an AM transmitter, however with a modulation depth of just 11 percent not broadband 

enough for a phase modulated FM transmitter.

 

Emperor Hadrian however also had the courage to build midst in Rome a temple 

calculated completely new and designed as a pure FM transmitter, the Pantheon, which 

means temple of all gods. In the language of the technician it is a transmitter for all 

frequencies.

 

This domed structure indeed doesn't leave out one single frequency. With a modulation 

depth of almost 100 percent it is designed for maximum loudness. With that the Pantheon 

uses all available frequencies, for which reason the name temple of all gods really is no 

exaggeration. Into the Pantheon exactly fits a sphere with a diameter of 43.2 meter. That 

corresponds to a minimum frequency of 3.47 MHz, situated in the range of the short 

waves. The floor however is not domed, but horizontal. That, up to the basis of the dome, 

results in exactly half the height and a maximum frequency of 6.94 MHz.

 

The construction ensures that between the simple and the double diameter any desired 

wavelength can be produced. Above the given maximum frequency of the basic oscillation 

the harmonic waves, which are produced as well and can't be avoided at all, are attached 

without a break. These occupy the wave bands up to the double, triple, quadruple 

frequency and so forth.

 

For this and only for this reason a maximum frequency was chosen, which corresponds to 

exactly the double value of the minimum frequency. The operation takes place to the limit, 

where the transmitter would interfere with itself, in the way that the used basic oscillation 

would overlap its own harmonic waves. That then sounds like two people talking at the

 

same time. The voices would be distorted out of recognition, as can't be expected else in 

the range of the harmonic waves.

 

The Pantheon has been planned and built as a phase modulated basic wave transmitter 

according to purely academic rules of Hadrian. The temple impressively demonstrates the 

precise engineering detailed knowledge of the Pontifex Maximus and his broadcasting 

priests in ancient Rome

.

 

:   A. Springer: Die Kunst des Altertums, A. Kroner Verl. Leipzig 1915, 10. Aufl., 

S. 517/518, daraus: die Zeichnungen ram Pantheon in Rom, 115-125 n.Chr.

 

: The collection of material concerning scalar wave technology here is aborted 

and continued in an own book in narrative and with that easier to read writing 

style. The title is: "Broadcasting Gods".

 

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