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Equipment Operation and Maintenance. Grid-controlled tube. Designed to turn on and off rapidly, providing short precise exposures Use in fluoro and in capacitor discharged (condenser-discharge) mobile units Uses a molybdenum focusing cup . FLUOROSCOPY. INPUT PHOSPHOR LARGE DIAMETER
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Grid-controlled tube • Designed to turn on and off rapidly, providing short precise exposures • Use in fluoro and in capacitor discharged (condenser-discharge) mobile units • Uses a molybdenum focusing cup
FLUOROSCOPY • INPUT PHOSPHOR • LARGE DIAMETER • CESIUM IODIDE • X-RAYS LIGHT • PHOTOCATHODE • LIGHT ELECTRONS • OUTPUT PHOSPOR • SMALLER DIAMETER • ELECTRONS LIGHT
FLUORO CONT. • FOCUSSING LENSES • VIDICOM/PLUMBICON • BEAM SPLITTING DEVICE • mA • ABS • AGC or ABC
FLUX GAIN=# OF OUTPUT LIGHT PHOTONS # OF INPUT LIGHT PHOTONS • MINIFICATION GAIN = Diameter of input (squared) diameter of output (squared • BRIGHTNESS GAIN: minification x flux
Trifield Tubes • 25/17/12smaller diameter of input phosphor reduces: field of viewmagnification minification gain dimmer image
Larger film formatgreater the # of films =higher patient exposure • Cinefluoroscopy • rapidly obtained photospot image (35mm film)15,30,60,90 frames per sec. • cardiac cath • Spot film • 12 frames per sec • smaller film size • cassette loaded
FLUORO QUESTIONS #9,24,30,36,38,40,44,47,54 63, 69,70
Collimation and AEC • Photodiode • light sensitive • under table, behind cassette • ion chamber • charge sensitive • above bucky and cassette • #10,14,25,27,34,81,92,102,113,
Self induction = autotransformer and choke coil • Mutual induction =High voltage transformer & filament circuit • V = VS = NS VP= NP • I = NS = IP NP=IS
Rectifiers • Filament circuit • rheostat • filament circuit
Motor and generators • Rheostat • Star and wye configurations • transformer windings in 3-phase circuits • 5,20,23,26,35,45,46 ,51,52,53,74,77
THREE PHASE/SINGLE PHASE HU • single phase=ma x time x kvp • three phase/ 6 pulse ma x time x kvp x 1.35 • three phase/12 pulse ma x time x kvp x 1.41
Single phase three phase 6 pulse three phase 12 pulse 100% 13% 4 or 3% ?’s 35,64,96,97,99,105,106 VOLTAGE RIPPLE
Tomography • Thinner the cut the _________the angle • 43
QUALITY CONTROL TESTS • SPINNING TOP TIMER • WIRE MESH SCREEN/FILM CONTACT • PENETROMETER KVP AND CONTRAST • STAR PATTERN FOCAL SPOT SIZE • CUTIE PIE ROENTGEN DOSIMETER • WISCONSIN TEST TOOL KVP IN BEAM • GEIGER RADIOACTIVITY
spinning top tests Spinning top tests • half wave/single phase = exposure time x 60 • Full wave/single phase = exposure time x 120 • Three phase –exposure time =arc size/360 • timers and rectifiers • dots and dashes(12 dots of 1/10sec, 24 dots of 1/5 sec, 6 dots for 1/20 sec) • synchronous spinning top • solid arc • #18,28,41,50,57,61,66,65,68,
TUBE LIFE/HEAT LOAD #6,12,16,33,44,73,77,101,
Mobile radiography, CT, Misc • Capacitors- temporarily stores energy-no battery • 2,3,4,22,37,42,55,58,71,78,87,88,120
DIGITAL Corectec
Misc. • Light absorbing dye in screens reduce diffusion of fluorescent light