Show Radio Device Assures More Comfort In Driving Noise Eliminated By New Tester By BT ISRAEL KLEIN Science Editor CA c Service Even the th bearings s of or your car carare carare are areso are so o finely tested that no noise or hum from them might discomfort fort you ou For this purpose a complete study of or noises and their sources was 88 made mad recently by at the th University ot or In conjunction with engineers for forone toron one of or the largo larl o bearing manu manufacturer The result of or this research was the Invention of or a delicate apparatus apparatus atus alue which detects the tho th slightest noise nolle In bearings above that considered considered con- con tolerable In motorIng This apparatus Is s desIgned some some- somewhat somewhat somewhat what like a radio receiving set with coils coll and vacuum lID tubes hooked up to a revolving bear bear- bearIng bearing las bear Ing so 0 as a to convert Its lis hum Into a visible l curve With It a deaf t person eron can hear the th hum or noise nolee of or the bearing BearIng noises It has lia been found result when the th hum they produce happens happen to b be In syn syn- synchronism synchronism synchronism with the tho th hum produced by the th gears rear In n the th transmission for tor Instance or any other moving parts of or the automobile Thus the tho tao t n noises n of or similar t pitch ae- ae accentuate c each other and make driving unpleasant Alone each cach might not even be b noticed ImE TREADS Much difficulty was as at first tint en- en en countered with the bearing hum humIn humin humIn In connection with the tho tb transmission slon sion Sometimes even ven the th sculpturIng sculpturing sculpturing turing In the tire tir treads brought ht out the gear cear or bearing noises noise through their synchronous hum Design n of or the tho th radio apparatus for Cor detecting the hum In n bearings now avoids any such uch possibility The machIne machin converts convert the th sound soun of the bearings Into sight so an that the human factor of error Is I dim elim- elimInated elim eliminated mated By setting the th limits between which a bearing noise Is consid consid- considered consid- consid considered considered ered harmless an observer at the machine can easily detect a detec- detec defective detec detective tive ti bearing when the dial over over- overreaches overreaches over overreaches reaches either limit rC TEJ S 3 SECO SECONDS mS Thus some om bearIngs are arte tested lcd each day for tor undue undu noise by this apparatus In three sec sec- seconds seconds cc the th observer can enn see eee ce whether whether er the tb bearing Is I defective detective By use of or this thia Instrument also bearings s found defective for or one purpose may be b perfectly good for another where their pitch orhum or orhum orhum hum would not coincide with the moving part In which they're to tobe tobe lobe be placed The Th radio Instrument consists consist or of ora ofa ofa a which Is if placed near the vibrating bearing re- re receives receives re receives the noise and passes passe It on through b an ordinary amplifier to toa toa toa a sensitive Indicator with dial ar- ar arrangement ar ement |