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Diagrams of the other details of the battery 



Detail 8 represents the interior or 

 contact panel which is best made of fiber. 



The contact slip-ring for the testing- 

 switch is shown at 9; 10 shows the 

 stop-pins for both switches. 



The spring ( 1 1) which keeps the testing- 

 switch contact arms out of contact with 

 the points, is clearly shown in Fig. 7. 



The locating spring (12) for'the testing- 

 switch, is also clearly shown in Fig. 7. 



Details I3and I4aretheswitcharniancl 

 friction springfor the high-tension switch. 



Detail 15 shows the centers of both 

 switches, and 16 represents the adjusting 

 collars for them. 



The bushings (17) for the switches, 

 should be forced in place in the hard 

 rubber front panel. 



Detail 18 is of the socket and flange for 

 the testing-lamp. Thisismadel)\' takinga 



A complete wiring diagram of the battery 



"pin-socket," procured from 

 an electrical supply house, and 

 making a flange as shown. 

 The socket is then soldered 

 into a hole in the flange and 

 filed down neatly, making 

 finally a flush socket. 



The hard rubber knob for 

 the high-tension switch is 

 shown at 19, the contact 

 springs for the testing-switch 

 at 20. These springs are cut 

 exactly as shown and bent 

 to suit. 



The contacts for the cells 

 (21), should be of very 

 springy material and like the 

 other parts, are preferably 

 nickel-plated in order to pre- 

 vent corrosion. 



Detail 22 is of the hard 

 rubber knob for the testing- 

 switch and is drilled around its periphery 

 to accomodate in the proper positions 

 the friction spring shown in detail 12. 

 It is suggested that the locating holes be 

 not drilled until the switch is assembled, 

 as this insures a much more accurate 

 arrangement of the holes. 



In assembling, the battery box is 

 first set up and the fiber panel screwed 

 on after having the contact-springs and 

 points mounted on it. Then the fiber 

 separators are pushed into place. The 

 next step is to assemble the switch panel 

 and mount it on its wood supporting 

 top. The switch-points used are stan- 

 dard X if- by X i"- heads having an 

 8-32 screw-hole at the back. The 

 connecting wires at the back arc best 

 soldered into small holes drilled into 

 the screws. The connections to the 

 battery contact points on the fiber 

 panel are also preferably soldered into 

 holes in the end of the screw shanks, 

 these points being the usual type. The 

 batteries used are the No. 603 pocket 

 flashlight cell. The length of the 

 battery box given in the drawings allows 

 y^ in. for each cell but it may be best 

 to measure up a set of cells and by 

 dividing the total length covered by the 

 number of cells obtain a fair average. 



The pointsof the testing-switch and cell 

 conii)artinents should he nuniiiered, so 

 that a defective (cll ma>- be jiicked out 

 immeiliately. 



