Okay, so this is the manyeth video I am watching on photodiodes and transistors, but this is the first, that mentions that the main difference is that the photodiode does not have a transistor built into it. Awesome vid!
Back in the business? Anyway, thanks a lot for your videos, I began the Raspberry Pi with your channel, and it was a great help as I started from scratch .
5y ago I started the project and forgot to finish it, now when reviewing what's in the box now I understand why the F had pair of non-working LEDs - they are IR ! :D
Can I use the phototransistor to measure the color of a light? It seems to me if I use 3 phototransistors. One with a red, another with a blue, and the 3rd with a green filter. Am I on the right track? The more sensitive the better I think.
Hi Gaven, thanks for the great video, was really helpful ! I was just wondering about calibration circuits for phototransistors to account for degradation of the LED or phototransistor ? Is that necessary , do they degrade quickly ? Thanks
I have a transistor with a clear case and a base connection, three pins. It responds to light. With a little light it looks like a transistor in a component tester. When it has a lot of light it becomes to back to back diodes with apparently no conduction. Interesting component. Can't find a list or number for it, to92 case. Very old.
It appears that using these methods, a photoresistor can be used to replace a LDR, if placing the 10k resistor after the phototransistor, and doing some experimentation. Is that a fair assumption? I am looking to modify a circuit using CdS based LDR's, which are becoming more difficult to come, with a better solution. However, I have not been able to find 3mm to 5mm, two leg phototransistors in a range of normal white light. Can I assume a clear phototransistor with a 850nm to 940nm high range would work? Thanks
Is there a single photo transistor that can detect one of the 7 light frequencies? To be clear I’d like the transistor to be capable of detecting all 7 colours but only detects the one relevant colour that’s shining onto the transistor, I hope that made sense lol
Hey Gaven! This is the first time I post something on your channel and I want to thank you for your videos, they have been really useful in helping me integrate my RPi with electronic components. However, I have been struggling a lot with the phototransistor videos. For example, I can't even replicate your setup on the breadboard and obtain the same results as yours. (or close enough). Would it be possible to share a schematic of your setup?. In my case I am using: an infrared LED (IR383) connected with a 330 Ohm resistor a phototransistor (PT1302B/C2) connected to a 10K Ohm resistor as indicated in the video 6V DC voltage Basically when I power the circuit the most voltage I get is around 0.30V instead of the 5V (or 6V in my case)
