Handicraft for handy boys; practical plans for work and play, with many ideas for earning money (1911)
Hall, A. Neely (Albert Neely), b. 1883- · Boston, Lothrop, Lee & Shepard Co · leaf 288
weight be heavy, for if it is, the detectorwill not operate at all. If you bend the needle slightly,it will be easier to keep it in position. The propermethod of connecting the detector to the other instru-ments is shown in Figs. 307 and 326. A Razor Blade Microphone Detector requires a base ofthe…
Woodwork · Toys · Amusements
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![An illustration from [Electric engineering.] (1902)](https://img.insideoutlibrary.com/img/200/ia-electricengineer03inte-302-180.webp)
