CH 6 Part 1 & 2 Flashcards
( T/F) medical X-ray units can either be diagnostic or therapeutic
What is the difference?
True
Diagnostic: general procedures
Therapeutic: treatment
Most common table top?
What must the X-ray table top be?
Bakelite
Radiolucent
Advantages of a curved X-ray table top and usually found with what?
More comfortable and allows the body part to be placed closer to the film = decreased OID
- found on fluoro tables
Disadvantages of a curved X-ray table top
- hard to do oblique or lateral positions, also decubitus and cross-table
- useless for table top radiography
Incoming current into the circuit is how many hertz and volts?
60 Hz
200-240 volts
Line compensator, what it does and why it’s used
Measures the voltage provided and adjusts it to 220 v
- incoming line (into the circuit) cam vary 5%
Single phase will drop to what, what did this mean for X-ray production?
0
No X-rays will be produced when at 0
Why is three phase full wave better than single phase unrectified
Because the power stays up since there’s multiple lines of power while single phase drops down to zero
Supplies the X-ray tube with modified power and to provide potential difference (kVp)
Main or tube circuit
-purpose is to produce X-rays
What supplies the filament with modified power and the purpose?
Filament circuit
- create enough current for thermionic emission
Why is the incoming voltage stepped down in the filament circuit
To increase current which is needed for thermionic emission
When you set the mA station you are adjusting the number of _____ flowing through the filament circuit which is adjusted by the _____
Amps
Variable resistor/rheostat
What is an increase in the mA that results from increased kVp because of the anode being more attractive to the electrons
Space charge
The tube/main circuit modifies the incoming power so the radiographer can control what (2)
Voltage and exposure time
What has a single winding and supplies voltage to the filament circuit and to the high voltage circuit of the imaging system
Autotransformer
What works my electromagnetic self induction
Autotransformer
Located across from the output terminals of the Autotransformer and monitors the voltage before the exposure is made
KVp meter
Monitors mA and is located at the secondary winding of the high voltage step up transformer
mA meter
What does the switch do
Turn power on and off
What does the circuit breaker do
Prevents overload (fire)
A remote controlled device to allow the flow of electrons through the circuit (begins exposure), activates the rotating of the anode
Exposure switch
(T/F) when designing room, the control console must be placed in manner that is impossible for the operator to be exposed
True
Monitors the product of mA and time to give the mAs desired
MAs timer
Automatically terminates the exposure when a predetermined density has been reached
AEC
