I have a solderless breadboard, multimeter, etc. on order, getting ready to dink around with some simple stuff to learn electronics.
I don't understand how to set up the power to the breadboard, for example, if I'm using a 9v battery and I need 5v. On the surface it seems like I could use a simple voltage divider, with 100 ohm and 80 ohm resistors in series which would give me 4v across the 100 ohm resistor and 5v across the 80 ohm resistor. But then when I start to connect things they'll be in parallel with the 80 ohm resistor and that will lower the resistance and change the voltage drop. So that doesn't seem like a good plan.
Or what if I want to use some wall wart I found in the dumpster? I have one that's 20v.
Or should I be thinking about using a voltage regulator like the LM2940T?
Confused and lost in newbie land, Rusty