File:Radio, miracle of the 20th century a story of human achievement that stands unrivalled in the history of humanity, together with a colorful portrayal, giving a broad, general view of the whole subject (14776644653).jpg

Identifier: radiomiracleof2000drin (find matches)
Title: Radio, miracle of the 20th century ... a story of human achievement that stands unrivalled in the history of humanity, together with a colorful portrayal, giving a broad, general view of the whole subject of wireless telegraph and telephone and its marvelous development
Year: 1922 (1920s)
Authors: Drinker, Frederick E. (from old catalog) Lewis, James G., (from old catalog) joint author
Subjects: Radio
Publisher: (Philadelphia, Printed by National publishing co.)
Contributing Library: The Library of Congress
Digitizing Sponsor: The Library of Congress

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Text Appearing Before Image:
would necessitate the lengthening of the lead-inwire. The accompanying diagram will show how the an-tenna is attached. Details of Parts—The essential parts are hereaftermentioned by reference to the letters as shown in Dia-grams (Fig.) 1 and 2. A. and I. are screw eyes which must be strong enoughto anchor the antenna at the ends. B. and H. are sections of rope % or % inch in diameter,just long enough to permit the antenna to swing clear ofthe two supports. D. is a piece of % or % inch rope of sufficient length tomake the distance between the insulators E. and G. about75 feet. MIRACLE OF THE AGE 153 C. is a single block pulley thai may be used if readilyavailable. The insulators E. and G. may be constructed of anyhard wood strong enough to withstand the strain of theantenna. Blocks of IY2 x 2x10 inches will answer the pur-pose. Holes should be bored at either end far enoughfrom the ends to give sufficient strength. If wood is usedit is best to boil them in paraffin for about an hour.
Text Appearing After Image:
Porcelain wiring cleats may be used instead of the wood,if they are available, but if unglazed porcelain is used itshould be boiled in paraffin the same as wood. The antenna is indicated by the letter F. suspendedfrom or between the insulators E. and G. Either insu-lated or bare copper wire No. 14 or 16 may be used forthe antenna. The end of the antenna furthest from thereceiving set may be secured to the insulator E. by anysubstantial method, but great care should be used not tokink the wire. The other end of the antenna wire shouldbe drawn through the insulator G. to a point where the in- 154 EADIOTELEPHONY sulators are about 75 feet apart. The wire should be bentback and the insulator twisted to form a shank of the an-tenna as shown in Figure 1. The loose end of the antennawill be the drop or lead-in wire and should be just longenough to reach the lightning switch. K is the lightning switch. For the purpose of a smallantenna this switch may be the ordinary porcelain-base,30 ampere,

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