116 6H4866-02Gain Tuning ProcedureThe procedure below applies to 200 ASA and 400 ASA. Only the X-ray settings in Steps 1 and 2 vary.200 and 400 ASA X-Ray Settings[1] Using the x-ray machine control panel, set the following X-ray settings for 200 or 400 ASA:(a) 200 ASA• 100 kVp 4 mAs (200 mA, 20 ms), SID=1.8 m, Large Focal Spot• Avoid the use of grid in this procedure.• Add 0.5 mm copper and 1.0 mm aluminum plates at the tube exit with the copper closest to the tube.• Measure the exposure using a dosimeter placed on top of the lead sheet or apron.• Adjust the SID to obtain the required value of 8.7μGy ± 0.5 μGy (1.0 mR ± 0.05 mR).(b) 400 ASA• 80 kVp 4 mAs (200 mA, 20 ms), SID=1.8 m, Large Focal Spot• Avoid the use of grid in this procedure.• Add 0.5 mm copper and 1.0 mm aluminum plates at the tube exit with the copper closest to the tube.• Measure the exposure using a dosimeter placed on top of the lead sheet or apron.• Adjust the SID to obtain the required value of 4.3μGy ± 0.5 μGy (~0.5 mR ± 0.05 mR).[2] Place a 14 x 17 in. cassette in the center of the field.[3] Make an x-ray exposure.[4] Wait 2 minutes after exposing the cassette.[5] Load the cassette into the Point-of-Care CR 120/140 System and click Scan.Screen Image in the Image Viewer screen[6] When the scan is completed, the image is displayed in the Image Viewer screen.
