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Nikola Tesla Books

Books written by or about Nikola Tesla

Nikola Tesla: Colorado Springs Notes, 1899-1900 Page 208

October 5, 1899

Table showing results. The capacities are all reduced to the same inductance so that as the primary capacity changes, the secondary is changed in the same ratio.

Height from ground feet Capacity in tanks Percent of increase Figures reduced to self-ind. of one primary:
20.66 4.36  
21.66 5.05 16%
22.66 5.77 14%
23.66 6.27 9.5%
24.66 6.00 0
25.66 6.24 4%

 

two primary turns reduced
25.66 6.64 10% To correct later factor $! {6.24 \over 6.64} $! to be used
26.66 8.87 33%
27.66 11.48 40%
28.66 14.84 30%
29.66 18.64 26%
30.66 21.08 13%
31.66 22.36 6%
32.66 23.28 4%
33.66 24.72 6%
34.66 25.68 4%
35.66 27.00 5%

Table showing results of observations on influence of height in determining capacity of a sphere connected to the coil before described. The sphere of 38.1 cm. electrostatic capacity was gradually elevated and the period of vibration determined for every position of the sphere, by varying the capacity and self-induction of primary circuit. As the self-inductions of both circuits remained the same the secondary capacity varied exactly as the primary.

208

Source:
by Professor Aleksandar Marinčić

October 5

Tesla checks the secondary coil adjustment. The procedure is already standard. He adjusts the capacitance and inductance in the primary (with coil of variable inductance connected in series) until he achieves the maximum sparks at the secondary terminals. Operating frequency is approximately calculated on the basis of total inductance and capacitance in the primary. The influence of the secondary adjustment to oscillation is checked by a sphere addition of 38.1 cm in diameter and because that has very little influence he draws the conclusion that the distributed secondary capacitance is large.

The same day he continues the notes by writing about the sources of possible errors when determining the variances of globe capacitance with height variance. He give the precise interpolation form according to which method applied on Oct. 4, the desired capacitances variances can be found.

Starting from some height, he has to change the primary coil (by reconnecting the turns in series a connection) due to the small maximum capacitance value in the primary.

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.