Identifier: designconstructi00pear (find matches)
Title: The design and construction of a radio telephone station
Year: 1921 (1920s)
Authors: Pearce, W. W Rosendal, D. L
Subjects:
Publisher:
Contributing Library: Paul V. Galvin Library, Illinois Institute of Technology
Digitizing Sponsor: CARLI: Consortium of Academic and Research Libraries in Illinois

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:
of four casesof dry cells. These were found suitable for theneeds of the occasion since only 10 to 20. milli-amperes were required. The input is from 5 to 10watts. This is an exanvcle of the general typeof vacuum tube radiophone set, ^?08t of the suc-cessful types are modifications of the above type. (SU (4) Alternators of Radio FrequencyThe big problem with this method is theconstruction of a suitable and dependable alter-nator which will produce an alternating currentof the extrenely high frequency necessary (100,000to 200,000 cycles). However, several of thesehave been brought out lately. These are all ofthe inductor type, because of their necessaryhigh peripheral speed. The Goldschmidt is oneof the best of these. In this machine the fre-quency is doubled within the machine by the com-bination of a to and fro motion with a rotation.The diagram is shown in Figure 8. Needless to say, the direct generationsystem is very simple and thus has many advan-tages over the ordinary arc sets.
Text Appearing After Image:
31 4. THEORY OF YACUUy- TUBES According to the theory now in vogue con-cerning the ultimate nature of matter, an atomconsists of a definite number of electrons groupedabout a nucleus having a positive charge* IJowso long as none of the electrons is driven fromthe atom, the latter possesses no detectableelectrical charge. But now let an electron be detached fron^the atom, then the a torn becomes what is knownas a positive ion and it exhibits the proper-ties of a positively charged body. Similarly, if an electron is added to anormal uncharged atom, the latter, in this state,possesses a negative charge and is terrred a neg-ative ion*. In suni/iarizing, we may say the posi-tive ion possesses a deficiency of electrons andthe negative ion an excess of electrons. Now, in order to liberate the electronsfran an atom we must disrupt or tear apart thelatter. The vacuum valve forms one of the bestexamiDles of a method for accomplishing this. s It has been known for many years that the spaceabout

Note About Images