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Show jj HANDICRAFT FOR BOYS AND GIRLS A. NEELY HALL and DOROTHY PERKINS (Copyright, by A. Keely Hall) A WIRELESS TELEGRAPH RECEIVING RECEIV-ING SET PART 1. With one or two exceptions a boy can easily construct the instruments of a "wireless" receiving set. The detector, shown in Fig. 1, requires re-quires a wooden base, A, a pair of dry-battery binding-posts, B, a piece of silicon, C, a strip of brass. D, and a piece of springy wire, E. Bind the silicon to the base with the brass strip, D, bending this as in nwird Fig. 4, and punching holes to fit over the binding-post. Bend the piece of wire E into the looped form shown in Fig. 5, secure one end to the binding-post, and cut off the other end to rest upon the piece of silicon. . The tuning-coil (Fig. 6) requires a cylinder about 2 inches in diameter and 11 inches long (A, Fig. 7). A rolling-pin with its ends sawed off will be Just right. On this cylinder a single iayer of copper wire of. about No. 20 gauge, not insulated, must be wound. It is necessary to keep each turn of the wire from coming into contact with the adjacent turns, and this is done by winding a heavy thread between be-tween the turns (Fig. 7). Two coats of shellac will help hold the coils in place. The end blocks (B, Fig. 7) should be 2 inches square, with a -ineh notch cut in each of two cor- () super in THREAD l: ners. Nail them to the ends of the cylinder cylin-der as shown. The slider rods (C, Fig. 6) should be of brass. inch square and 12 inches long, ar-d should have a hole drilled at one end to receive binding-posts D (Figs. 6 and 8), and a pair of holes through which to screw the rods to blocks B. You can get the brass rods and have them drilled, at almost any machine shop. Make sliders E (Figs. 6 and 9) out of a piece of springy brass. Bend one end into a sleeve to slip over the slider-rod. and round off and bend down the other end to slide over the surface of the wire coil. Scrape away the shellac in their path. Fasten a post to one end block B. and connect an end of the wire col', to It. The fixed condenser (Fig. 101 is made of alternate layis of tin-foil and ' writing-paper. Cut two pieces of cardboard of the si?e of A (Fig. 12i. for the top and bottom (Fig. 111. then 21 pieces of i 3'- i : writing-paper of the same size, lor layers B, and 20 pieces of tin-foil of the size and shape of C t Fig 13). Build up the condenser as shown in Fig. 11, with the tabs of the tin-foil layers projecting over the ends, and with alternate layers reversed. When the top cardboard has been put in place, take two pieees of insulated wire, scrape bare a length of eix inches of each, and run these bared j ends through the top cardboard and j wrap around the tin-foil ends (Figs. 10 I and 11). Then wrap the condenser J from end to end with bicycle tape. ! In the nest article you will learn how to connect up the instruments. nd bow to make the aerial. THREE GOOD GAMES TO MAKE. There Isn't much work to the making mak-ing of a checkerboard like that shown in Figs. 1 and 2. Twelve Inches and one-quarter square is a good measurement te use. This provides for 64 squares each one inch and one-half in size, and a margin of one-eighth inch around the outside. It is better to use cardboard than wood, because of its lightness, and if you will hinge two pieces together as In Fig. 2, the checkerboard check-erboard will slip into a bookcase. To prevent the cardboard from warping, warp-ing, it is necessary to paste paper up-on up-on both sides. The black or red pa- per s best for covering the back. Paste this on first, lapping it a distance dis-tance of one-half inch over the edges of the playing surface; then cover the playing surface with the lighter-colored paper of the two you have selected select-ed for the squares. When the pasted paper has dried, measure off the width of the margins and the squares along the four edges of the playing surface, and with ruler and pencil rule lines across from side to side, from these points. This will give you the positions of the 64 squares. Hunt up small silk spools for the checker men. You will need 24. Fig. 3 shows how a short peg should he cut to fit in the top of each spool, so one spool can oe fitted over another an-other to crown the men (Fig. 4)" Twelve of the spools should be stained black cr red, so they will be distinguishable distin-guishable from the other twelve. Figs. 5, 6 and 7 show the homemade home-made game of jackstraws. Inasmuch as you may never have played this game. I will explain that it consists in removing "straws" from a pile, without disturbing any "straws" but I he one selected for removal. A player's play-er's turn continues as long as he can remove the "straws" without disturbing disturb-ing the pile. Fig. 5 shows how the "straws" ars dropped In a heap, and how they are removed by means of a hooked stick. Fig. 6 shows how the "straws" are r1e of toothpicks with pieces of teaf - jj H ' JtM -I i-iPPo ., rardboard cut to the shapes of shovels, rakes, pickaxes, etc., glued to the H-.ids. and Fig. 7 how a pin bent into a hook, is bound with thread to a pencil pen-cil ond. for the hooked stick. Put numbers upon the "strav.s" for the puiins to be counted as scores. The shopping game in Fig. S embraces em-braces a new idea. Get a cover from a hitge hat box for the playing board; then cut pictures of various household articles frum advertisements, paste these upon the inside of the covor (Fig. in, and mark the prices of the articles upon thera. You must also have a Mna.ll spinning top. One of the wheels from a broken alarm clock ( Fi- Hu is best. Two or more can play the game. Each player has a turn to spin the top upon the playing board, V hen after spinning, the top topples over, the price of the article upon v hich its point rests will represent repre-sent Tlie numbr of -points scored. |