GE AMX-II

GENERAL ELECTRIC MEDICAL SYSTEMS AMX-ll X-RAY UNIT
1-981 SM A0654E
14-3 Large Field Size Check ce
г
А
initial Conditions: ANODE C a
Same as Section 14-1. |
1. Position a loaded 14” x 17” (35.5 cm x 43.2 cm) cassette
under the collimator (17” (43.2 cm) dimension transverse (1.016 m)
to the axis of the tube unit). Using the collimator meas- 40”
uring tape set the source-to-image distance at 40” (1.016 m).
2. Adjust the blades to yield a field size of 14” x 17” (35.5
cm x 43.2 cm). Place a coin on the cassette to identify
the anode front corner of the x-ray field.
& 3. Make a 50 KVP, 1 MAS exposure and develop the film.
n (35.5 cm) 러
14”
4. If cutoff in the transverse direction is observed, lead 22005-D20
finger spacing of the collimator should be checked. Refer
to Chapter 4, Part |, Section 5-4. ILLUSTRATION 4-11-43
14-4 Field Lamp Voltage Check
To meet HEW requirements, the voltage at the collimator lamp socket must be at least 19.6 VAC (RMS)
at a minimum battery voltage of 110 VDC. This is an indirect test of illumination level.
NOTE: Because the lamp voltage is a square rather than sine wave, the voltage measured with a Fluke
8000A Digital Meter will be greater than the true RMS value. Lamp voltage can be measured
with a true RMS calculating digital meter such as a Weston/Schlumburger, Mode! 4445. How-
ever, do not use an iron-vane AC voltmeter because it will overload the lamp circuit.
. Lu. 6-32 x 1/4”
Inital Conditions: FRONT UNC HEX SOC.
NAMEPLATE SET SCREWS
Same as Section 14-1.
Instrumentation:
Battery Voltage: digital voltmeter from section 13.
1. Remove the Blade Control Knobs and the
collimator front nameplate.
a. Loosen two 6-32 unc x 1/4” hex soc. set screws
at the top front of the collimator frame.
b. Tilt the nameplate forward enough to clear
the knob shafts and lift out. REMOVE BLADE
- CONTROL KNOBS
ILLUSTRATION 4-11-44
4-11-35