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Nikola Tesla Books

Books written by or about Nikola Tesla

Nikola Tesla: Colorado Springs Notes, 1899-1900 Page 87

July 15, 1899

Colorado Springs

July 15, 1899

Some arrangements in telegraphy involving the Dynamo principle (first brought to Page some years ago). Present apparatus built two years ago in New York, worked very well. Consider which the best of the following modifications: In case 1. Sensitive device a with battery around field F.

In armature circuit independently a receiver R and battery B1. The receiver may be a relay, and in addition, to insure greater sensitiveness another sensitive device as a, may be joined in convenient manner in the armature circuit. In case 2. the armature and field circuits are joined in series and battery and receiver are in shunt to both, also sensitive device a. In both cases the sensitive device may be also in series with the field or field and armature though arrangements 1 and 2 seem preferable. In arrangement 3. a shunt dynamo is shown, the sensitive circuit being also in shunt to the terminals of the dynamo. In addition, to regulate excitation of dynamo a shunt of high self-ind. is placed around the sensitive device a. Such a shunt may also be used with good effect in Fig. 2.

Fig. 4 illustrates one of the dispositions with an alternate and - preferably - high frequency dynamo. The letters are self-explanatory. The sensitive device a1 may be omitted.

87

Source:
by Professor Aleksandar Marinčić

July 15

Earlier on (see the entry for June 3rd) Tesla presents a general scheme in which the ‘dynamo principle” is referred too as one of the ways of accumulating energy from weak signals. The circuits given here illustrate how he implemented this principle. The “sensitive device” has a resistance which varies as a function of the antenna signal, and is connected so as to alter the excitation of a DC (Figs. 1, 2, 3) or AC (Fig. 4) dynamo.

Although he says that apparatus using this principle had already worked well in New York, none of these receivers, nor the principle they embody, appeared in any of his patents.

Source:
by Professor Aleksandar Marinčić

July 15

In the beginning of notes (please see June 3), Tesla gave the general schematic where ''dynamo principle" is mentioned as one of the energy accumulation methods for weak impulses received from a distance principles. The given circuits show how Tesla does that in practice. The sensitive device is the device which reduces the resistance in the event of signal reception from the antennae and it is connected such that it causes the excitation of the dynamo by direct (Fig. 1,2,3) or by alternating (Fig. 4) current.

Although he mentions that these devices operated well on this principle, some two years before, in the New York laboratory, none of these receivers, or even the principles, are included in some of the patents in the field of radio technique.

Contents

Introduction
June 1 - 30
July 1 - 31
August 1 - 31
September 1 - 30
October 1 - 31
November 1 - 30
December 1 - 31
January 1 - 7
Commentaries

Appendices: I, II

Images

Glossary

Lowercase tau - an irrational constant defined as the ratio of the circumference of a circle to its radius, equal to the radian measure of a full turn; approximately 6.283185307 (equal to 2π, or twice the value of π).
A natural rubber material obtained from Palaquium trees, native to South-east Asia. Gutta-percha made possible practical submarine telegraph cables because it was both waterproof and resistant to seawater as well as being thermoplastic. Gutta-percha's use as an electrical insulator was first suggested by Michael Faraday.
The Habirshaw Electric Cable Company, founded in 1886 by William M. Habirshaw in New York City, New York.
The Brown & Sharpe (B & S) Gauge, also known as the American Wire Gauge (AWG), is the American standard for making/ordering metal sheet and wire sizes.
A traditional general-purpose dry cell battery. Invented by the French engineer Georges Leclanché in 1866.
Refers to Manitou Springs, a small town just six miles west of Colorado Springs, and during Tesla's time there, producer of world-renown bottled water from its natural springs.
A French mineral water bottler.
Lowercase delta letter - used to denote: A change in the value of a variable in calculus. A functional derivative in functional calculus. An auxiliary function in calculus, used to rigorously define the limit or continuity of a given function.
America's oldest existing independent manufacturer of wire and cable, founded in 1878.
Lowercase lambda letter which, in physics and engineering, normally represents wavelength.
The lowercase omega letter, which represents angular velocity in physics.