Show simplicity 0 OF F RADIO by POWEL CROSLEY JR 3 ANOTHER illustration OF TUNING with a piano and a violin we may ery easily demonstrate the principle I 1 upon which radio tuning P Is based first of all we must remember that tightening a violin string siring makes it vibrate more rapidly giving out a note of higher pitch while loosening it makes leakes it vibrate less rapidly giving out a lower note first we will loosen all the bolln strings until they hang with practically no tension then we will strike a key on the piano feeling 1 I the violin strings with our finger at piano and violin may so bo used mufed to illustrate resonance the same time to see it if they vibrate in unison with the alarin note no vibrations t will be felt be beaise ause the Dil natural tural vibrating period of the violin string when loose will be much lower than that ot of the plano piano string makh Is struck next we will vill gradually tighten one of the bolln strings causing it to have a higher and higher natural vibrating period we will strike tin ill piano note at frequent intervals during this process of tightening und and when tho the string lias has been adjusted to the lie tension at which it glies ghei out a note of the same ditch as the piano note that Is at which its natural vibrating period Is the same as that of the piano string it ill vibrate very forcibly whenever the piano note Is truck struck As the string Is tightened still further its response to tile piano note will grow loss less stud and less until it finally sinks into non thus thu w we e s sec ee that strings in musical inspru ments will respond to each others other s sounds it if they are tuned to the same period ot of vibration aud and if it Is decided that ore oce string shall respond to another one that Is in a state of 0 vibration it Is necessary to tune it to ta the e period of the vibrating string the response of radio sets only to the particular period to which they tire are ad austed involves the same fundamental principles to bece ve a broadcasting station on our radio set we must tune it by turning tile the dials to tile the particular station we desire to hear there Is another fact that we can learn from the strings if the violin string is tuned to an octave below or abone the piano note it will respond though not so well to the vibrations of the plano piano string tills this Is 1 known as tile phenomenon of harmonics when e n tuned one octave below the piano note the violin string tends to vibrate half as fast as the plano piano string and when tuned one octave higher it tends to vibrate twice as fust fast thus when an octave apart the strings are to a certain extent in tune with each other und ind will respond to each other to some degree harmonics play an important part in determining the quality of music and of the voice in practically all sounds or musical tones a great number of harmonies harmonics tire are present the violin owes its musical quality largely to the higher harmonics or overtones the organ depends upon the lower notes and lower harmonics for its pecullar musical timbre thus it Is important in radio transmission and reception that the harmonics of the sounds at tile the broadcasting studios studio be perceived |