Mohave County miner and our mineral wealth., 1922-05-19

charge up to the same potential as
 the battery. If the battery is ther
 removed the condenser will force the
 current back in the opposite direction
 until the condenser has acquired zert
 potential.
 It is thus seen that weight and in.
 ductance are similar and also that elasticity and capacity are similar
 Inductance and capacity in an electri, cal circuit act the same as a spring and a weight in material body. That is, if they are furnished with energy from some outside source, they will oscillate back and forth until they finally reach state of rest.
 Thus we see that an electric circuit will oscillate if it contains both cap acity and inductance. if a current is once started in the circuit. B. these l'oscillatiUnsro to-and-fro movements of the electrons, ether waves fradio fwaveslsare started. Since the velocity is always constant, the length of the waves depends upon their frequency, as above stated. The frequency may be changed by changing either or both the inductance or capacity. Increas- ing either the inductance or the cap- acity, the same effect as increasing the weight on the end of the hack saw blade or decreasing its stiffness by lengthening its blade, causes a de- crease in the frequency, and therefore a. longer wave length. Therefore, to increase wave length we increase either or both the inductance or cap acity, and to dcerase the wave length we decrease either or both the induc- tance or capacity.
 A straight wire has little self-in- ductance. A coil of wire has a con- siderable amount of self -inductance. By changing the number of turns of wire in coil we change the induc- tance of the coil. Due to the construc- tion of coils it is easily seen that these changes in inductance must be made in steps, 1t being difficult to construct a contact which can be slid around the coil and touch only one wire when the wire is wound with the turns next to each other. Capacity is changed readily be making a con- denser having a set of stationary plates and a set of movable plates, the movable set turning on a shaft and so arranged that they will pass between the stationary plates. As the amount of the capacity of tho con denser is determined by the amount of the surface of the movable plates which is covered by the stationary plates, or vice versa, it is seen that a very fine adjustment of capacity may be made, and hence an accurate ad- justment of wave length obtained with any given amount of inductance in the circuit. It is chiefly by this means that the radio. receiving sets which may now be purchased are operated in order to "tune in" on any given wave length. ..
 Next issue: "The energizing of Capacity-Inductance circuits and the reception of radio waves"
 QUESTIONS and ANSWERS. (All questions should be addressed to the Radio Editor. No signatures will be printed with any questions ap- bearing in this column.) Hl
 Q1. Do have to have Govern ment License to operate a receiving set with which I can hear the Los An 1 geles stations? F. ev
 Al. No. Licenses are required only for transmitting stations and no h- cense is required for any type of re- ceiving apparatus. >::'
 Q2. Can I use a3galena receiving set in Kingman? M. K. R. AZ M. K. R. Receiving sets using any mineral will probably give good results in Kinglnan and this vicinity but for efficient work and satisfactory work the ;audion bulb xdtscter should be used,' the audiont Ab sbeing much more sensitive than any mineral. %r;, !
 Q3. How can I construct an aerial that will work with an Aeriola Senior Receiver? L. S., Oatman.
 (Continued On Page 1D