Show 5 g Z pa PRO am 15 ea large wire necessary for A C Fi filaments larnen ts in the of sets that uro urd to ile be operated from batteries basterl es tile question que allun of tile size of tile the filament wl wire re rarely enters this Is due both to the comparatively low current required for far each tu tube be and the fact that u slight flight difference in the voltage applied to each tube makes little or dir difference ference in tile the operation of the receiver in ili tile the case of receivers using raw A C tubes the situation Is quite different the current required by encil each tube Is very much higher lil glier tile type for example draws 11 amperes W it if an attempt Is made to operate several filaments in parallel with a single twister conductor run iriti ning successively to the ove five tubes several will arise due to the higher current there Is 18 A correspondingly higher voltage drop along the alie filat ilent this me mentis its that untie it potential difference may exist between the lie hasl arid and tile the lust last tube it if tile wire Is s ea enough alah tile the reduced vurr current may tie be of it lit lin the I allily IC serious trouble however Is that tills this dro drop p in the alla ment circuit Is impressed as an alternating terna ting e i in t f on oil the grids of tile lie tubes a 0 the file usual circuit anent elds trouble Is quite noticeable in tile the radio frequency amp liller the set may be perfectly quiet with no DO signal A carrier will then be received und and the hum immediately be becomes collies noticeable tills this Is due to the A U C e in t modulating the carrier tills this Is then rectified by t lie detector le end and becomes audible to overcome this two things should I 1 bu be done first arst large wire should be used to make the drop very small then to prevent the difference tit in drop to different tubes occur occurring rind leads of approximately tile the same saine length should be run from a common distria distribution u t lo 10 point if say three stages of radio frequency tire are used then the feeder should go to the second singe from it n comi tion point perhaps six inches from the file socket two pair of twisted conductor should eliou ld he be run to tile the first and third stage tubes respectively ively where tle leads are of up proximately t lie he same length I 1 no 18 wirt will be found I 1 tory in other jalcs about no 14 should tl be used volume control means for radio receivers experimenters who have attempted to adapt some joule of it the lie volume kolunie control methods used in D 0 receivers to A L 1 sets have found that it was gossl bitto get it good I 1 or lo 10 ion vt kolunie aunie point tills this trouble occurs when the lie volun volume ie control Is used in the llie circuit of a radio frequency tube ahead of tile the detector tills con control I 1 rol ut uell it I 1 1 consists of a vur variable lable resistance shunt ed sa one of if the he i tuners clr culta the alia reason for inability to red reduce ace tile lie signed to zero Is that the power line Is arillia us as a title line odthe of lie currier carrier current type aylie acting as the line doer in ili wired vired wireless and bringing tile the high frequency signal into the he set gli the plate supply unit there inny he sufficient signal impressed Impre saed on the detector to give rood good reproduction pen even when the volume control la Is set for no signal to overcome this it Is necessary to affer a very high impedance to to tile the frequency currents to chole choke them out A cradit badlu frequency e clinks I 1 i P I 1 p hould be inserted in the fre paille supply lenit lend at the revolver A 01 or 02 nilca should then he connected from the re celver side of tile the choke to the grid return lead potentiometer mill tap speaker should not be placed above radio set the quality ut of programs program 11 s now bivall ivull lible deserves the best possible eill edl cleney ciena in reproduction loon it Is a well fact that the torte tone qua quality illy oh ob miller is is depe dependent not only mily on i alie lit eill of the speaker but on I 1 19 is Im sillion in the room another well known fact Is 9 that it Is undesirable to tn pince the dl kwlly keelly above tile radio set this Is easily eusley tested hy by mosing tile lie ahdout over oer tile lie top of if the lie set when it will he noti noticed ved lint alint distortion oe oc curs sit as the lie colls roine come wi within tilli the lie frequency field of the llie frequency inning units the short shortness ness nf at the usual rord cord often Interfere ps with pla 1 chip the llie reproducer to host best advantage in the room this IS in now easily overcome hy by mann of extension cords dully dally for this purpose on anle tit nt nt most stores thorps |