X-ray field alignment
MAMMOMAT Balance
SPB7-115.840.01 Page 55 of 62
Siemens AG
Troubleshooting Guide
Rev.02 10.04
Medical Solutions
•
Insert a 18x24 cm collimator
8383205
.
•
place a coin on a corner of the table as a reference, expose with 26 kV 40 mAs and
develop the film.
•
Measure the two distances
A
between the side border and the dark zone of the film.
Measure the two distances
B
between the film front edge and the dark zone of the film (see
figure). The measures must be taken starting from the darker zone of the film, because the
shaded zone is not useful.
•
The two distances
A
must be the same (excluding the clearance of the film in the
cassette).
•
The two distances
B
must be the same within 1 mm. They must be included between
17 mm and 22 mm.
•
If the two distances
A
are not the same, it is necessary to trim the position of the RX
tube shifting it to the right if the right distance is shorter than left, and vice versa. Consider
that shifting the tube for 1 mm causes the shifting of the borders of about 4 mm.
•
If the two distances
B
are more than 22 mm, it is necessary to trim the position of the
RX tube shifting it back. If the distances are less of 17 mm, it is necessary to shift the tube
ahead. To shift the tube, operate the screws shown in the next picture .
Reference coin
Screws to remove
or shift RX-tube