Exploring the X-Ray Fluorescence CMI900: A Journey Through Repair and Discovery
0:07 Introduction to X-Ray Fluorescence: X-ray fluorescence is introduced as a technique for analyzing the elemental composition of materials, particularly metals.
0:17 The Challenge: The video begins with a broken X-ray fluorescence machine purchased off eBay, which sustained further damage due to poor packaging during shipping.
0:54 Initial Assessment: The machine, a CMI900 Oxford Instruments unit, is shown to be capable of both elemental analysis and coating thickness measurement.
1:09 Repair Begins: The first video focuses on the repair of the unit and its accompanying PC, addressing both mechanical and electrical issues, as well as extensive damage to the PC.
1:54 Interlock System: The machine has four interlock switches to ensure safe operation of the X-ray source, highlighting a focus on safety.
2:39 X-Ray Unit: The core X-ray unit, containing the source, detector, and motors, is removable and connected by a mass of wires.
3:33 X-Ray Tube Controller: A dedicated board manages the X-ray tube and various interlocks.
3:49 High Voltage: The unit uses a 115W linearly connected transformer and a separate high-voltage power supply for the X-ray tube.
4:07 X-Ray Fluorescence Head: The main X-ray fluorescence head is examined, revealing a stepper motor for stage movement, a camera for sample viewing, an X-ray tube, and an X-ray shutter.
5:31 Camera Test: The camera, initially suspected to be faulty, is tested independently and found to be functional.
7:30 Sample Analysis Area: The area facing the sample contains numerous optical and mechanical sensors for proximity detection and collision avoidance.
8:32 Detector: The detector has a stepper motor-controlled window with an interlock switch.
9:39 Reassembly: The unit is reassembled with about 6,000 zip ties, and the high-voltage power supply is reconnected.
10:49 Computer Issues: The accompanying PC is in poor condition, with damaged components and a broken hard drive.
12:25 Computer Repair: The video card is replaced, the hard drive is cloned to an SSD, and the PC is made operational.
13:17 Further Troubleshooting: After getting the software working, no signal is detected during measurement attempts.
13:53 X-Ray Verification: A radiometer is used to confirm the presence of X-rays, indicating that the X-ray source and shutter are functioning.
14:14 Detector Tube Bias: The high-voltage power supply for the detector tube is identified as a potential issue.
14:53 High-Voltage Power Supply Repair: The high-voltage power supply is found to be faulty, with a failed PNP transistor in the oscillator circuit. The transistor is replaced, restoring the power supply's functionality.
17:57 Additional Issues: Further problems are discovered, including malfunctioning optical detectors for stage limits, dead LEDs for sample illumination, and a misaligned camera.
19:39 Final Steps: The identified issues are addressed, and the unit is prepared for further testing and analysis.
19:55 Preview of Next Video: The next video will cover the theory of operation and include a range of measurement experiments.