LITHOSTAR Multiline
RXL2-120.815.01
Page 16 of 18
Siemens AG
System manual
Rev. 02
02.05
CS PS 24
Medical Solutions
6 - 16
Checking the Dose Rate
•
If the potentiometer adjustment range is not sufficient (experience has shown this may
occur), change to switch S2 on board D100 and repeat the adjustment.
•
As soon as the adjustment has been successfully completed, exit the window with OK
and return to the main SSW menu with "System quit."
Dose setting
Preparation:
- Release a test exposure with 70 kV, 2.1 mm Cu in the beam path.
•
Attach the dose measurement device at the I.I. input and check the dose rate at all zoom
levels with the dose values previously set for the PDA sensor adjustment (in the Edit
Dose Nominal Value window).
Remarks:
The nominal values do not include the attenuation of the measurement chamber and the
grid. The following values should be measured:
If a value deviates by more than + 15 %, the value must be correspondingly changed in
the Components Multiline menu under Adjustment-Nominal Value.
•
Exit the menu with System Quit and repeat the procedure, if necessary, for the next
measurement check.
Image brightness for DR
6
Preparation:
- Set 70 kV for DR image, 2.1 mm Cu filtration in the beam path.
•
Measure the image signal in the line center (60 Hz approx. line 128, 50 Hz approx.
line 156) between the Videomed DI output (D1.X1) and the Memoskop input (X9) with an
oscilloscope to reach the same image brightness for a DR image as for fluoroscopy.
•
Perform the adjustment for all zoom levels.
The voltage signal should be 300 mV, the same as for FL. To check this, switch between
DR and FL.
•
If case of deviations, change the value of the associated "DR Zoom x" in "am7 TV Iris"
under "Parameter Groups" (For larger values, the image becomes brighter and the
voltage increases and vice versa.)
Zoom level Nominal value w/o grid (nGy/s)
Measured value with grid
(nGy/s)
Full format
278
461
Zoom 1
640
1062
Zoom 2
1056
1753
Zoom 3
1056
1753
