Show no 18 wire Is am ample P ie for filament circuits thae exists a general slon that it Is necessary to wire the t he filaments and beaters of A 0 tub tubes es with lb inordinately large and cumbersome wire due to the relatively heavy y filament drain of such tubes white while there Is a certain amo amount u at of justification for this assumption in the case of the low voltage tubes the 27 and 20 26 types the stipulation has been exaggerated ag even in such cases it never should be necessary to use larger than no 18 solid wiring for filament pu purposes reposes it Is very seldom that more than four tubes are carried carrie d on a single circuit special circuits being employed for detector and power tubes splitting three ways vie the current sop con to the re celver and reducing the vi voltage drop in the lea leads as considering si the requirement cheaver the average re receiver cel the numbers of tube P used and the length of leads the difference bet between wen the voltage drop dip occasioned i boded in no 18 wire and in ed cd no 14 wre represents an incan sequential e i n bial part of possible g e variations riat ions due to allne etc also transformers 1 ers generally are arc fitted L with primary current control which are arc used to obtain th the correct tube vol see regardless of bf line voltage or voltage drop in leads it is Is interesting 16 to n ohe note i tha that recent experiments in n the lab laboratory laborati da a the arcturus ra ila dlo dio con company pany show that heater cathode tubes of the 27 type actually are more mord sensitive defect detectors ors nt at Voltage from 10 to 25 per cent below the recommended heater beater potentials I 1 i with high rollag voltage e A a tubes as the Arct arcturus drus line f heater amilt fler detector and power tubes tube consuming only 34 ampere the wire usually employed tn in battery sets can to bo used without consideration of current brair drahn pr voltage drop |