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
38
R22
1/A
- R221
/A DHHS -
Option
al Ite
m
s
Ralco
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OPTIONAL ITEMS
This collimator may have the following optional items; a detailed description is provided in this
chapter.
RO 001/A Fixed Mounting Flange
Thickness of this mounting flange is 20 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
.