The Amateur Electrician's Workshop (Volume 1); A Handbook of Practical Instruction in the Making of Electrical Models and Appliances (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated.1908 Excerpt: ... leaping across the spark-gap in the plug to the metal of the cylinder, and thence home again through M B. 40 Annexed is a table of the dimensions, gauge of wires, etc., required in the construction of these two coils: --HOW TO MAKE A LINESMAN'S DETECTOR, WITH TWO COILS. 41. A galvanometer, capable of indicating the presence of currents of considerable quantity (in amperes), or of fairly high pressure (in volts), is an invaluable instrument, not only to the electric bell fitter and telegraphist, but also to the practical electrician in general, as it enables him to ascertain the state of his battery and connections, as well as the presence or absence of leakage in the circuit. The following directions will enable any worker, who is gifted with a little patience and neatness, to make up an instrument of this class, which, if purchased, would cost at least 30s, for about as many pence. The materials required are one or two empty cigarboxes (cedar, if possible, as this takes a good polish), some thin sheet-brass (about 3 ins. by 6 ins.), not more than in. thick, a yard or two of No. 20 d.c.c. copper wire, one ounce of No. 36 silk-covcrcd copper wire, three Post Office pattern terminals, a few No. 6 sewing needles, a strip of sheet brass about 3 ins. long, in. wide, in thick, a few small wood screws, one Tg-in. metal screw, a narrow strip of thin sheetsteel (out of a pair of stays will do nicely), about in. wide, in. thick, 3 ins. long; a sheet of clear glass, about 3 ins. by 4 ins., from which will be cut the glass front of the case; a piece of white cardboard for the dial, a little solder, and a strip of the thinnest pos sible sheet aluminium (for the pointer or index). Furnished with these, the operator will begin by making a case out o...