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Accessories for MWL100 system system include the motorized Translation Stage, the motorized 3-axis Rotation Goniometer, the Automated Orientation Base for Barrel Holder. These items require the Motor Driver with joystick control.
To see detailed overview, please click on items listed on the left.
Crystal Orientation Stages
The
Three-axis Rotation Goniometer provides remote alignment of crystal
samples within a radiation enclosure. This goniometer is ideal for
sample manipulation over large angular ranges. The Goniometer is operated
through the motor driver.
The
Automated Orientation Base for single crystal orientation has been
designed to allow remote control of the two axes of a barrel holder
with two DC motor driven allen wrenches in the power pod. The automated
barrel holder base is mounted on a standard x-ray track. The barrel
holder can accommodate crystals to a maximum weight of 2.2 lbs (1
kg) and can tilt the crystal ± 7o
on both orthogonal axes. This unit is designed to operate with the
automated motor driver which can produce a 0.04o
step size with adjustable speed of 0.04 to 0.8 o/sec.
The power pod can be manually rotated through 360o
about the barrel holder axis. A manually adjustable allen key locks
the front plate of the barrel holder when orientation has been completed
on a crystal.
Automated Motor Driver
The Automated Motor Driver with joystick control has 6-axis capability to drive 12 or 28 VDC motors at up to 2 A per motor. A joystick controls the motors a pair at a time. The rotary switch allows selection of one of three of the pairs. The motor speed is varied by changing the rate at which full voltage pulses are delivered to the DC motor. This ensures full motor torque even at low motor speeds. Light emitting diodes on the joystick pod indicate the return motor current.
| Angular range, (deg) | Minimum step size, (deg) | Speed, (deg/sec) | |
| X-axis | -60 to +60 | 0.02 | 0.02 to 4.0 |
| Y-axis | -30 to +30 | 0.02 | 0.02 to 4.0 |
| F-axis | 0 to 360 | 0.02 | 0.02 to 3.0 |
Translation Stage
The Translation Stage is used for vertical and horizontal positioning of crystal orientation devices and samples. The stage assembly will easily accommodate a weight load to 110 lbs (50 kg). Positioning of the samples is accomplished with the 6-axis, joystick-controlled motor driver.
| Range of travel, (cm) | Minimum step size, (cm) | Speed range, (cm/sec) | |
| Horizontal | 10 | 0.008 | 0.008 to 2.54 |
| Vertical | 6.7 | 0.013 | 0.013 to 0.51 |
X-ray Detector
The X-ray Detector is a multiwire proportional chamber with a 30 cm x 30 cm active area. The detector is equipped with four interchangeable collimators (0.5, 1.0, 2.0, and 3.0 mm), a fail-safe x-ray shutter, and a gas delivery system ( 90% Ar, 10% CO2 gas mixture).
Electronics
Rack mounted instrument modules:
Modules by EG&G Ortec:
4001A/4002A Nim Bin and Power Supply
556 High Voltage power supply
Three 551 Constant fraction discriminators
PEC 535 Quad fast amplifier
EG&G 661 ratemeter
Modules by Multiwire Laboratories:
Dual time-to amplitude converter and digitizer, model 4
Gas delivery module, with an inlet flow gauge and over-pressure protection hardware.
PC Computer (includes custom PC interface card to Laue camera electronics).
X-ray Source
A standard focus tungsten x-ray tube is used that is continuously adjustable over the range of 9 to 25 kV and 1 to 20 mA, full-wave rectified or constant potential. The 9 to 20 kV operation is essential for crystals containing significant quantities of elements that may fluoresce in the 5 to 20 keV range. Low voltage operation will minimize the production of fluorescent x-rays which are also imaged by the detector system.
Power to the x-ray tube is controlled by Spellman DF3 power supply.