Show care in connecting jacks for amplifiers where vacuum tubes and n number of steps of amplification are used it Is sometimes advantageous to bo be able to connect in on tile tho detector tube or on one or more stages of amplification telephone jacks are a great convenience bence to those who ft ho know lioy how to connect them for this purpose it connected improperly they aro are sources of constant trouble jacks are generally used to shift from one stage to tile the next there are arc other types tyna which may bo be wired aired to control automatically the filament current this arrangement la Is a convenient one and results in a great saying of battery power Il wiring tile the licks in nn amplifier circuit Is a difficult problem and unless the builder has some same knowledge of them it Is best to leave them alone an amplifier jack poorly wired will the efficiency of the set as a whole it Is best to avoid the use of flux or soldering paste when soldering the lie connections to the terminals of the telephone jacks at times builders make laako nn an untidy job of this so that when the flux Is heated it soaks through and finds its way to the pa L above Is shown a two circuit jack below the single circuit jack per washers that lie ile between the contact connections of th tho jacks tills this prevents most of the energy from taking its proper course and tho the result Is a weakened signal there are three types of jacks used in radio circuits namely open circuit jack the close or two circuit jack and the automatic filament lighting jack they are shown in the accompanying compa nying diagram there are also a few jacks of peculiar mako make which ire re rarely used |