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4-40
P/N 9-500-0255
Service Manual
Chapter 4: Calibrations and Performance Checks
Performance Checks
6.6
Bucky Device Performance Check
Perform this check before utilization of a new SRL 2000 or HTC Bucky device. This
procedure requires the user to make exposures to check for grid lines (SRL 2000 Bucky) or
grid patterns (HTC Bucky) on the developed film.
Mount the 18 x 24 cm Bucky device on the IRSD. Be sure the electrical connection is made.
This procedure requires exposing and developing films. It will be necessary to place
attenuation between the tubehead and the Bucky for these tests.
Note…
Use the same Bucky device, cassette, and film type for all exposures.
1. Rotate the C-arm to 0°. Set the unit for an Auto-Time, 25 kV exposure, Large spot, Nor-
mal density. Select the Film Type being used.
2. Place a loaded cassette in the Bucky device, then place 2.0 cm of BR-12 (or PMMA
acrylic) on the Bucky Device. Hold the attenuation in place with the Compression
Device.
3. Make an exposure. Verify a low mAs reading is obtained (nominally between 12 and 40
mAs, dependent on film speed). If the mAs reading is above or below the specified
range, add attenuation to increase mAs, or remove attenuation to decrease mAs.
4. Reload the Bucky (using the same cassette and film type), and repeat the exposure. Ver-
ify that the mAs falls within the specified range. If it does, remove the cassette and
develop the film. Verify the absence of grid lines (SRL 2000 Bucky) or grid patterns (HTC
Bucky) in the developed film.
5. Place 5.0 cm of BR-12 (or PMMA acrylic) on the Bucky and hold it in place with the
paddle. Reload the same cassette with the same film type, then load it into the same
Bucky.
6. Make an exposure using the technique factors from Step 1. Verify a high mAs reading is
obtained (nominally between 200 and 400 mAs, dependent on film speed). If the mAs
reading is above or below the specified range, add attenuation to increase mAs, or
remove attenuation to decrease mAs.
7. Reload the Bucky (using the same cassette and film type), and repeat the exposure. Ver-
ify that the mAs falls within the specified range. If it does, remove the cassette and
develop the film. Verify the absence of grid lines (SRL 2000 Bucky) or grid patterns (HTC
Bucky) in the developed film.
8. Repeat Steps 1 through 7 with the C-arm rotated to -90° (grid travel in the direction of
gravitational pull). Verify the absence of grid lines (SRL 2000 Bucky) or grid patterns
(HTC Bucky) on the developed film for all exposures.
9. Repeat Steps 1 through 7 with the C-arm rotated to +90° (grid travel against the direction
of gravitational pull). Verify the absence of grid lines (SRL 2000 Bucky) or grid patterns
(HTC Bucky) on the developed film for all exposures.
10. Repeat the entire procedure for the 24 x 30 cm Bucky Device.
6.7
AEC Limits Performance Check
This check verifies that the system automatically terminates exposures whenever the
automatic exposure control circuitry senses that optimum film density cannot be obtained
within the 5 second maximum exposure time. To comply, the system must terminate
Auto-Time exposures below 5 mAs.
1. Place a lead blocker on the IRSD so that it blocks the AEC sensors within the IRSD.
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