Ralco MTR 221/A, Инструкция по эксплуатации

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MTR221/A - MTR221/A DHHS
MANUALE ISTRUZIONI / INSTRUCTION MANUAL
Modello/Model R221/A - R221/A DHHS
O
PTIONAL
I
TEMS
40
R22
1/A
- R221
/A DHHS -
Option
al Ite
m
s
Ralco
srl
RO 051 Rotating Mounting Flange
This accessory is used to rotate the collimator assembled to the X-ray tube.
• Flange thickness: 18 mm
• Flange diameter: 136 mm
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.
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
.