. Dental and oral radiography : a textbook for students and practitioners of dentistry . directly to the regulating chamber and passing asmall amount of current through the circuit. These manipulations should be carried out with the 112 DENTAL AND ORAL KADK iCIIAIM I V greatest caution, for a tube is an extremely delicate andsensilIre piece of apparatus and will not stand careless operator can quite easily reduce the vac-uum to such a degree that the tube is useless. Such atube lias a purple appearance when the current is passedthrough it. If such a tube lias nol been too greathalmsed,
. Dental and oral radiography : a textbook for students and practitioners of dentistry . directly to the regulating chamber and passing asmall amount of current through the circuit. These manipulations should be carried out with the 112 DENTAL AND ORAL KADK iCIIAIM I V greatest caution, for a tube is an extremely delicate andsensilIre piece of apparatus and will not stand careless operator can quite easily reduce the vac-uum to such a degree that the tube is useless. Such atube lias a purple appearance when the current is passedthrough it. If such a tube lias nol been too greathalmsed, it will often regain its vacuum if given a rest. Ifthis does not bring the vacuum up, it can often be broughtback in the following way: The spiral spring (Fig. 59)connecting the anode and assistant anode should be re-moved and the positive wire from the machine attached A— ode. U- -Assistant Anode C—Cathode D— RegulatingChamber F—Regulating Ad-juster G—Hemtsphci <■ H—Conncchon WireI—\sststanl Anode CapK —Anode CapL—Cathode OpM—Cathode Sin amN—local Point. Fig. 59. to the assistant anode (7). The negative wire is at-tached as usual (at L) and a light current is run throughthe tube for a minute or two at a time. If this is doneonce or twice a day for several days, the vacuum willusually come up. Any increase in vacuum will be indi-cated by the milliampere readings dropping off, or bythe increased length of spark gap the tube will backup. If a tube does not respond to this treatment but con-tinues to be purple while operating, it indicates that itis practically nonvacuous or punctured.; It is thenuseless and should be sent back to the manufacturer for DENTAL AND OEAL EADIOGEAPHY TECHNIC 113 repairs. In the event a tube is completely punctured,3the current in passing through it simply jumps the gapbetween the anode and cathode, and is evident as a lineof white sparks. One tube complication not yet mentioned is sometimesencountered in the use of induction
Size: 1640px × 1523px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthormcc, bookcentury1900, bookdecade1910, bookiddentalorcco
