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3

This is absolutely doable. In fact, depending on the TV, you might not even need to record the sequence because you can just look it up. Lots of sites like THIS exist, that have databases of IR codes. All you need is a small µC to send out the pattern and the IR LED, resistor, and a transistor. The circuit itself could be as simple as this: simulate ...


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Actually, polarizers are good filter for this case. Buy a sheet from amazon ~$12, cut it and stack that 90 deg. It blocks visible light (red glow) and allow near infrared to pass. Remember not to block the camera if your led is right next to it. In my case it works really well though you still see a tiny bit in pitch black room. My baby doesn’t stare at it ...


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TX IR LED Working Voltage : 0.9 - 1.3V Reverse Voltage : 5V Forward DC : 30mA You can drive an IR LED with higher current pulses (more than 30mA) as long as the maximum average current spec is not exceeded. If you power the LED from 3.3V using a BJT (0.1V Vcesat) and a resistor to limit current, there will be 0.9-1.3V on the LED, and 1.6V minimum on ...


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The ir sensor has filters for 8550nm(1169cm^-1), 8750nm(1143cm^-1), 9650nm (1036cm^-1), 12250nm (816cm^-1). Also your typical methane detector is at 3300nm(3000cm^-1) so alot of these line up with the absorbance peaks, do you think this will work as a detector? That detector is meant for measuring the concentration of a known gas in a purified form. It ...


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with only four measurements such a sensor will only be able to detect pure THC, there will be 4 innocuous substances that when mixed will confound the measure sufficiently that detection of trace amounts of THC will not be possible.


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I think you will have an issue with false positives because of the overlap peaks with other compounds. Depending on what your tolerance specifications for false positives might be, you may prefer a more accurate method. Why reinvent the wheel, nature has already supplied us with a quite accurate specific compound detection method; canine olfactory ...


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As earlier answer mentioned, yes its doable but I would not recommend it. Raspberry PI I/Os are pretty delicate and with a few additional components you could create a solid solution. The way you are using an NPN transistor doesnt seem to be right. I would suggest you use FET/Transistor to mimize the current you draw from the 3.3V rail. Additionally since ...


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Welcome to the site Michael. If you are only powering 1 LED over ~15 meters, I'm assuming your LEDs are around 20mA max and require maximum of 2V. You should be fine powering them off the 3.3V rail (mind it has a 50mA maximum current limit). Using just about any 2 conductor wire from 18-28 AWG. You should use some sort of relay or transistor instead of ...


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So (and this is an Edit after reading some of the great and informative answers and comments) - A receiver circuit should be simple to build and connect the analyzer into it? What about software to 'understand' the IR codes? https://www.sbprojects.net/knowledge/ir/ My preference is to burn an mcu for this rather than try to use interrupts but either way ...


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I did this as a class project in college. The remote LED frequency is very low, and codes are only a few bytes, so almost any analyzer will work. If such an analyzer it enough to achieve this mission, can one guide me please what a circuit I have to build to be able to catch the signals from the IR RC led? You don't need to build anything. Just open the ...


4

Thermocouples are more likely to give an accurate reading (of the junction temperature). The relationship between the junction temperature and what you are trying to measure is another matter, but it's unlikely to be really disparate if you are careful (for example, extending the thermocouple wire inside the heated zone and coiling it against the PCB to act ...


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