We are very happy to find a broken spectrophotometer in our lab because we can finally apart something. So we took it apart and examine what’s wrong with her. And we found except the gauge head and transformer, other parts were in good function. So we decided to save her! It only took us 40 yuan to make her enjoy popularity again. We bought some electronic components and breadboard. And we replace the old gauge head with the LED display made by ourselves, to show the numbers under the working of old transformer. And this is the birth of our educational spectrophotometer. It can show the students how spectrophotometers work and how to use primary electronic elements to make display. What’s more it can freely disassemble. That’s really killing three birds with one stone.
Step 1: Prepare the Material and Tools
The tools we prepared are: a set of screwdrivers, a multimeter, a pair of tweezers, wire stripper and etc.
The material we prepared are: a broken spectrophotometers, NE555, AD0809, 74LS48, LEDs, resistors, capactiors, wires, diodes, a laboratory stabilized power supply unit and etc.
Step 2: Find Out the Failure Part of the Broken Spectrophotometers
After a long-time test and examine, we found gauge head and transformer broke down, probably due to using for a long time without maintenance.
And here is a video about the inspection of the broken spectrophotometers.
Step 3: Fix It
The old gauge head almost didn’t response to the electricity. Considering the transformer can still work in some kind of way, we decided to replace it with other display to make it easier to compare the transmittance of the sample in cuvettes. And we chose the cheap LEDs and DAC(digital analog converter) to make our display.
Step 4: Assemble LEDs and DAC
Firstly, we used the Multium to make the schematic diagram and stimulate the process on our computer. With the right stimulation, we built it by the components we bought and inspect if it can work properly.
Step 5: Set the Display Up to the Broken Spectrophotometers
So here is the most important part! By this, we will let the broken spectrophotometers revive! We make the wire, which connected with the gauge head, connect to the display we built. So it can show the numbers for us to measure the transmittance of the sample.
Step 6: Prepare the Sample
It’s so lucky to get the EMDM from our senior. Ready to test our machine in 600nm.
Step 7: Test the Educational Spectrophotometer
This is the result of the sample by our Educational spectrophotometers. And we compare it with the result conducted by new ultraviolet spectrophotometer. We must admit that even we advanced our way of dispaying the numbers, the influence of stability of transformer is still very strong. The display can’t change number by itself. So it is not suitable for scientific research, but to let students know how the spectrophotometers work and the function of DAC. As the same time the component can recycle in anytime. Furthermore students' creation can be improved a lot by using our machine. that's awsome! Come on! Put your finger on the "Vote"!
And here is a video about how to make it:
Here is a video about our team:
Runner Up in the
Green Electronics Challenge (Chinese-language)