List of my videos https://www.youtube.com/c/electronzap/videos https://www.youtube.com/@Electronzap/community for most of the diagrams I've used in my videos. https://www.amazon.com/shop/electronzapdotcom As an Amazon Associate I earn from qualifying purchases. Americans should check out one or more of those links before making any purchases. There's no extra cost to you. https://www.patreon.com/electronzap https://electronzap.com/ https://www.reddit.com/r/ElectronicsStudy/ In the previous video, I goofed. I used a 10k resistor on the board in place of the 3k resistor I wrote on this diagram a long time ago. I added notation, but am following up with a video to talk about why that is not a problem since adjusting the value of resistor(s) is a common part of modifying a circuit you see in schematic form. Light dependent resistor (LDR) voltage divider changes a signal voltage, based on how much light is falling on the LDR versus the value of a (Usually, but not always) fixed resistor on the other side of the divider. Operational amplifiers (op amp) compare the non inverting (+) input to the inverting (-) input when determining the output voltage. The output tries to me more like the + input. Therefore, the output will be high when the + input has a higher voltage than the - input. Whereas the output will be low when the + input has a lower voltage than the - input. Without feedback, the output is either as low of a voltage as it can give, or as high of a voltage as it can give. #Electronics #Howto #diy ... https://www.youtube.com/watch?v=kNnHlR7qjIM