I bought a PWM Dimmer based on a 555 from AliExpress to regulate the brightness of a 12V 1A 1 meter LED strip, I already built one myself years ago on a perfboard but this one was the exact dimensions I needed for a project. I built mine from components from AliExpress and components found in old electronics so I thought nothing functionally would change The dimmer is this one https://www.diymore.cc/products/pwm-10a-speed-regulation-led-dimming-ultra-high-linearity-band-switch but I attached a real photo of the one I got from AliExpress My problem is that it isn't doing any regulation while connected to LED strips, I tried with the 1m one and with another light that has three 30cm LED strips in parallel Every other light or motor I connected to it seemed to make it work. I really have no idea what could be causing this, maybe it's sensible to capacitance? LED strips are two long straight parallel contacts but I don't think it's enough to cause anything as displayed here in the video: https://live.staticflickr.com/video/53017878188/54f865d36d/1080p.mp4?s=eyJpIjo1MzAxNzg3ODE4OCwiZSI6MTY4ODMxNzgwMCwicyI6ImI2MjZiMzk3MjExNTQxZWIyOTYwYzAyNTRmZDNhZDZjZTcwOWUxOGYiLCJ2IjoxfQ

Please no prejudice on that oscilloscope, it's good for what its made for, it's "calibrated", it shows a clean square waveform on my simple diy dimmer (photo to let you see what I mean with simple) versus what is shown in the video with the AliExpress one, an hybrid ramp/square. In the first part I show one of those LED strip that doesn't work, in the second part I show one that does work, just like every other light or motor I've tried