I've dabbled in electronics since my parents gave me a 150-in-1 kit in the 1970's but never had formal training. My dad repaired Honeywell mainframes so taught me to solder when I was 8. I have a decent set of equipment like irons, parts, meters, etc. and realize I know enough to be dangerous, which is why I avoid mains-powered stuff. I'm not a newbie but am all too aware of the many holes in my knowledge. I'm doing this for fun and in a way that allows for failures to be expected, cheap, and educational.
I have a WS2812b LED strip connected to an Arduino Uno and am using various animation libraries to drive it. The goal is to move to a pro mini once the hardware is more settled and use it for creative lighting inside my house or garage. I started with just the strip and let it display different animations in a sequence based on time but then wanted to attach a button which would advance to the next animation. After implementing debouncing it worked fine and I moved on to adding a potentiometer to select the speed of the current animation; increasing or decreasing the delay between each 'frame'. Of interest here is I was using old pots (panel mount not for typical board use - hence I had to solder wires to them just to use them in any configuration) and not doing any ohms law calculations, just hooking up the hardware and tuning the values for mapping the detected voltage to the desired delay by checking printed output from the serial monitor.
I'm happy with the general setup when using a breadboard but when I went to solder something more permanent on perfboard I ran into a problem; the speed control wouldn't work. I'm sure the first pot I used was 10k but when I checked it with the meter it registered as completely open so I figured I had blown it. Thinking that I needed to control the current I read posts like this one and this one about limiting current I felt better and proceeded to replace the pot with a 25 ohm version thinking that the only difference would be in calibrating the values for mapping the detected voltage to the desired delay. The behavior I got was randomly fluctuating values for the delay and when I hooked up the prototype using USB to my laptop I could see that the analogread() values were fluctuating wildly within a range even when I wasn't manipulating the pot yet nothing I did could get it to be consistent. My first thought was that there was a problem with ground so I rechecked the connections but they all tested fine, including still reading 25 ohms along the outside terminals and varying values on the wiper consistent with rotating it along its path from end to end. When I gave up on my protoboard and returned the circuit back to the breadboard I replaced the full size pot with a 10k small one meant for breadboards and the speed control works again. This leads to my question.
Is there a minimum value for a potentiometer connected to an analog input of an arduino, or is it more likely that there was an issue with my soldering job on the protoboard? I don't have a picture of the board because I've already desoldered components from it but I can tell you that it was my first attempt at perfboard soldering and it would not win any prizes, sort of the 'face only a mother could love' sort of thing. If it matters, I was using analog input A2.