Ralco R 221 ACS DHHS Series, Инструкция по эксплуатации

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MTR 221 ACS - MTR 221 ACS DHHS
MANUALE ISTRUZIONI / INSTRUCTION MANUAL
O
PTIONAL
I
TEMS
173
Model R 221 ACS - R 221 ACS DHHS
MT
R
2
21
ACS
-
MTR
2
21
AC
S DHH
S - Optio
nal Ite
m
s
RO 445 Metal Rotating Mounting Flange
Metal rotating mounting flange:
• 20 mm thickness
• +/- 90° mechanical stop
• 140 mm diameter
Please refer to the chapter INSTALLATION in this Instruction Manual for the correct flange/
collimator mounting instructions.
When the collimator is assembled check the collimator to Focal Spot Alignment
(Primary Shutter Cut-Off).
Inspect the four images of the four collimator shutters which form the edges of the X-ray
field. A definitely indistinct edge indicates that the primary shutter, close to the focal spot, is
the one forming the line, rather than the outermost shutter.
To correct the condition, use the four mounting/centering adjustment screws to shift the
collimator in the direction of the indistinct line. Repeat the test film exposure after making
the adjustment.
N
OTE
T
HE HEEL EFFECT WILL CAUSE THE FIELD TOWARD THE CATHODE TO BE
SLIGHTLY LESS SHARP THAN ON THE OTHER THREE SIDES
.
THIS IS NORMAL
AND CANNOT BE CORRECTED BY ADJUSTMENT
.
IN ADDITION
,
AN X
-
RAY TUBE
OF
12°
OR LESS TARGET ANGLE WILL PRODUCE AN ASYMMETRICALLY SHAPED
FIELD WHEN A LARGE FIELD SIZE IS USED AT SHORT SID
,
BECAUSE OF ANODE
CUT
-
OFF EFFECT
.
THIS IS NORMAL AND MAY NOT BE CORRECTED BY
ADJUSTMENT
.