User:Mu301/wireless

Spark-gap

Spark-gap transmission bandwidth

figure	wavelength (frequency)	full bandwidth	type of tuning
A	500 metres (600 kHz) — 1,200 metres (250 kHz)	~350 kHz	untuned
1	775 metres (387 kHz) — 1,025 metres (292 kHz)	~95 kHz	very badly tuned
2	850 metres (350 kHz) — 975 metres (307 kHz)	~43 kHz	properly tuned
3	875 metres (343 kHz) — 950 metres (320 kHz)	~23 kHz	most modern type, very sharply tuned

Emission bandwidth of spark-gap transmitters

• 
  "Characteristics of a commercial transmitter on shipboard showing broad range of waves sent out."
• 
  "Characteristic of improperly adjusted transmitter showing double waves."
• 
  "Characteristic of preoperly adjusted transmitter showing single wave."
• 
  "Characteristic of transmitter of most modern type showing very sharply defined wave." (Quenched-spark transmitter)

• Kolster, Frederick A. (18 January 1912). "Statement of Mr. F.A. Kolster". Radio Communication. Hearings Before the Committee on the Merchant Marine and Fisheries. US House of Representatives. Washington: US Government Printing Office. pp. 64–70. H.R. 15357. Retrieved 10 October 2023.{{cite conference}}: CS1 maint: date and year (link)

• Kolster, Frederick A. (1915). "charts". Experimental Wireless Stations. By Edelman, Philip E. Minneapolis, MN: Philip E. Edelman. pp. 61–65. ISBN 978-1362557616. Retrieved 7 February 2023.

Bands

Wireless band limits

wavelength (frequency)	allocation
— 200 metres (1,500 kHz)	amateur limit
300 metres (1,000 kHz) — 600 metres (500 kHz)	commercial
600 metres (500 kHz) — 1,600 metres (190 kHz)	government
1,600 metres (190 kHz) —	commercial (long distance)

Wireless bands before and after the Radio Act of 1912

• 
  Overlapping usage, and interference, between amateur, government, and commercial wireless operators before the US Radio Act of 1912.
• 
  Amateur, government, standard commercial, and high-power commercial (for long distance) bands defined by the US Radio Act of 1912.

• Worts, George F. (October 1913). "How the New Wireless Law Works". Popular Mechanics Magazine. Chicago. pp. 545–547. Retrieved 6 February 2023.

Massie

Fall River Line

Steamship	Call
Priscilla	CA
Pilgrim	GM
Chester W. Chapin	HN
Providence	PV
Plymouth	PX
City of Lowell	WE

400 meters, 1 kW

• "Wireless Telegraphy on the Plymouth". Providence Sunday Journal. April 3, 1904. p. 17.

• Massie, Walter W; Underhill, Charles R. (1908). Wireless Telegraphy and Telephony Popularly Explained. New York: D. Van Nostrand. p. 21.

• Telegraph Stations of the World: 1907

• Ward, John (June 12, 1966). "The New England Wireless and Steam Museum: Right back to the days of the cat whisker". Providence Journal.

• "Walter W. Massie, Pioneer In Radio Field, Dead at 66". Providence Journal. January 22, 1941. p. 12.

GWEN

• Foster, Nancy (November 1988). "Citizens jam nuclear radio network". Bulletin of the Atomic Scientists. Vol. 44, no. 9. p. 21. Retrieved 24 January 2020.

Tests

• 2,182 kilohertz (137.4 m) = 137.4 metres (2,182 kHz)
• 150 millimetres (5.9 in) 6 inches (150 mm)
• 150 mm = 5.9055 in

Symbols

• = equal
• ≈ approximately
• ≠ not equal
• ≡ identity
• ≃ asymptotic equality