Q AmatQur • 

 Electrician 



I'^nd Wii'Gless Operator 



Resonant Annunciator to Operate on 

 Alternating Current 



HERE is a method of constructing 

 an annunciator to operate on a 

 110-volt alternating current that is very- 

 simple, yet efficient. There are no spark- 

 ing contacts in this annunciator; never- 

 theless it admits of a wide range of tone 

 adjustment and gives forth a powerful 

 buzzing note that is exceptional because 

 of its unusual resonance, its extremely 

 low pitch and enormous volume. The 

 pitch may be regulated to a higher fre- 

 quency and smaller volume, which may 

 be necessary when the far-reaching, low, 

 powerful note is not desired, as may be 

 the case when there is someone ill in 

 the house or where for any other reason 

 it is necessary to minimize the noise of 

 the instrument. 



The annunciator consists of nothing 

 more than a 75-ohm w^atch-case receiver. 

 The cover of the receiver should be un- 

 screwed nearly all the way when the low 

 pitch is desired. By screwing the cover 

 on tighter, the pitch is raised. To secure 

 best results, the receiver should be 

 mounted at an angle slightly off vertical, 

 or in other words, with the face of the 

 receiver-cover tilted downwards. A 60- 

 watt lamp or something equal in resist- 

 ance to it should be placed in series 

 with the annunciator in order to lower 

 the amperage of the current passing 

 through it and thus serve to protect its 

 windings. 



The device will consume hardly any cur- 

 rent at all and an ordinary push button 

 may be used; but the wiring and insula- 

 tion should be much heavier than for 

 ordinary battery annunciators. It is, of 

 course, readily understood that the buzz 

 produced is the effect of the rapid alterna- 

 tions in the current. — Joseph Braff. 



Making a Night Light of Battery 

 Cell and Miniature Lamp 



A SIMPLE, yet efficient night light 

 can easily be constructed by follow- 

 ing the instructions outlined in the ac- 

 companying illustration. If the necessary 

 materials are not at hand, they may be 

 purchased at any electrical store. The 

 base and the upright are made of wood, 

 and fastened together with two flat- 

 headed screws. A felt pad, cut to shape 

 and pasted on the bottom, will prevent 

 the polished surfaces from being scratched. 



CLMi/IP 



-SMALL LAMP 



PUSH BUTTON^ 



A dry cell placed on a base with upright 

 to hold watch and lamp for a night light 



The battery is held in place by a wire 

 bound around it and attached to a staple 

 on either side. The lamp, preferably a 

 2 3^- volt tungsten, is connected in series 

 with the button and battery. For running 

 the wires from the lamp to the back of the 

 board, insulated staples should be used. 



A twisted No. 20 lamp cord is used. Its 

 length depends upon the distance between 

 the bed and the article upon which the 

 night light is to be placed. The sketch 

 shown above makes the construction 

 clear. — H. Neuhaus. 



