Identifier: corelessinductio00smit (find matches)
Title: Core-less induction coils in telephone service
Year: 1907 (1900s)
Authors: Smith, Claude E Stewart, Walter M
Subjects: Induction coils Telephone Telephone systems Theses
Publisher:
Contributing Library: University of Illinois Urbana-Champaign
Digitizing Sponsor: University of Illinois Urbana-Champaign

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
'
Text Appearing After Image:
6 The secondary was now moved about a common diameter of the twocoils, (see diagram 5 of coils) through the same angles as before,but the point of silence was even more difficult to find. Therewas a more sudden entire deminishing of sound as the ninty degreerelation was nearly reached. The intensity of sound did not de-crease as rapidly from zero degrees to ninty degrees, as in theformer case, and also did not decrease as much. Both coils were novi wound On the same rim, but, as near as v/ecould distinguish, there was no difference between the transmis-sion of the voice by that arrangeme/it, and the tmnsmiission of thecoils wound on seperate rims, and at a distance of one inch apart. We wound a secondary coil on a wooden spool, ten inches in dia-meter, with turns of #36 copx)er wire, giving a resistance of188 ohms, and as a primary, 3J turns of # 25 copper v;iro v;ound ona 39 i:ich bicycle rim. This coil when compared with the largecoreiess coil of seperate windiiigs, was found to tra

Note About Images