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 (1922)
Drinker, Frederick E. [from old catalog], Lewis, James G., [from old catalog] joint author · [Philadelphia, Printed by National publishing co.] · leaf 183
armwith knob shown at V, Fig. 3, may be purchased in theassembled form or it may be constructed from a thinslice cut from a broom handle and a bolt of sufficient 160 EADIOTELEPHONY length equipped with four nuts and two washers, togetherwith a narrow strip of thin brass somewhat as shown.The switch… … individual tap fastened under the head or soldered tothe projection of the nail through the panel. The switchcontacts should be just enough that the switch arm willnot drop between the contacts, but also far enough apartthat the switch arm can be set so as to touch only onecontact at a time. The…
Radio
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