Long time programmer starting to learn about electrical engineering a little bit. I have a Raspberry Pi, an Arduino, and various simple projects I've soldered together out of kits and schematics friends have given me.
Recently I moved and lost many of my AC adapters. I found I was able to use different ones from other devices. AC adapters from devices such as the original kindle, old accessory USB AC adapters, old and new Apple AC adapters, and many others that do not have a USB input but rather the older style (I forget the name of the connector on the end, some sort of DC power connector Arduino UNO's have one).
So an example of what I'm asking is this: What effect does it have using say an Amazon kindle AC adapter (or any other mismatched brand adapter) with an iPhone lightning to USB cord?
Specifically, my Arduino/Raspberry Pi are using random usb min/micro cables plugged into completely random AC adapters. Most of which have no indication of their specifications. What effect could this have? I have another dubbed a "Fast Charger" that puts out (from what I can tell) 2-3 amps based on the voltage.
Another example would be the Arduino DC power connector, I also have the same connector on a small breadboard power supply. I find anything that fits seems to work in there. What effects might this have?