The X-ray Unit/Imaging System

Question 1

it is used to provide controlled flow of electrons that it is intense enough to produce x-ray beam

Answer 1

x-ray unit or imaging system

Question 2

three components of xray unit

Answer 2

operating console
high voltage generator
xray tube

Question 3

it is the part of the xray machine most familiar to the radiographer

Answer 3

operating console

Question 4

the number of xrays; mR or mR per mAs

Answer 4

quantity

Question 5

it is the penetrating quality of xray beam kVp or half value layer

Answer 5

quality

Question 6

it incorporates a meter to measure the voltage provided to the x-ray machine and a control to adjust that voltage to precisely 220 volts

Answer 6

line compensation

Question 7

it is designed to supply a precise voltage to the filament circuit and to the high voltage circuit of the xray machine

Answer 7

autotransformer

Question 8

some older xray operating consoles have labelled major and minor kvp by selecting a combination of these controls, the radiographer can provide precisely the required kvp

Answer 8

kvp adjustment

Question 9

it allows the voltage to be monitored before an exposure

Answer 9

prereading kvp meter

Question 10

it is where the number of electrons emitted by the filament is determined by the temperature of the filament

Answer 10

mA control

Question 11

as filament current increases, the filament becomes ___ and more electrons are released by _____ emission

Answer 11

as filament current increases, the filament becomes hotter and more electrons are released by thermionic emission

Question 12

filament normally operates at the current between __ to __ amperes

Answer 12

filament normally operates at the current between 3 to 6 amperes

Question 13

it causes the x-ray tube to emit for a specific time as determined by the radiographer or by an automatic exposure control

Answer 13

exposure timers

Question 14

five types of timing circuits

Answer 14

mechanical timer
synchronous timer
electronic timer
mAs timer
automatic exposure controls

Question 15

it is a timing circuit that are very simple devices used only in some portable and dental units and it operates by a clockwork

Answer 15

mechanical timer

Question 16

it is a timing circuit that is a special type of electronic motor and is a precision device designed to drive a shaft at precisely 60 revolutions per seonds

Answer 16

synchronous timer

Question 17

it is a timing circuit that are the most sophisticated, most complicated and most accurate of the x-ray exposure timers

Answer 17

electronic timer

Question 18

it is a timing circuit that most xray apparatus is designed for accurate control of tube current and exposure time

Answer 18

mas timer

Question 19

it is a timing circuit that it automatically terminates the exposure when sufficient radiation to provide the required optical density has reached the image receptor

Answer 19

automatic exposure controls

Question 20

this evaluates the length of time that the xrays produces

Answer 20

evaluation timer

Question 21

it is responsible for converting the low voltage from the electric power company into a kilovoltage of the proper waveform

Answer 21

high voltage generator

Question 22

it is a step up transformer where the secondary voltage is higher than the primary voltage

Answer 22

high voltage transformer

Question 23

what do you call a ratio of the number of secondary windings to the number of primary windings?

Answer 23

turn ratio

Question 24

is the process of converting alternating voltage into direct voltage and therefore alternating current into direct current

Answer 24

rectification

Question 25

represents a condition in which the voltage is not allowed to swing negatively during the negatively half of its cycle

Answer 25

half wave rectification

Question 26

in a full wave rectified circuit the negative half cycle corresponding to the inverse voltage is reversed so that a positive voltage is always directed across the xray tube

Answer 26

full wave rectification

Question 27

this results in pulsating xray beam

Answer 27

single phase power

Question 28

multiple voltage waveforms are superimposed on one another, which result in a waveform that maintains a nearly constant high values

Answer 28

three phase power

Question 29

the newest development in high voltage generator design uses a high frequency unit

Answer 29

high frequency generator

Question 30

the parts of an xray unit are identified by their power rating in kW

Answer 30

power rating

Question 31

power = ____ x ____

Answer 31

power = amperes x volts

Question 32

is the variation in peak voltage waveform

Answer 32

voltage ripple

Question 33

three phase six pulse = __% ripple

Answer 33

three phase six pulse = 13% ripple

Question 34

three phase twelve pulse = _% pulse

Answer 34

three phase twelve pulse = 4% pulse