The Racetractor. The End.

[zx_volcane]

The best thing you can do is go away and read up on how it all works. Must be some online courses available on the basics.

I'm sure I keep suggesting to go through the Arduino tutorial examples or to build some small example circuits on breadboard.

Get a good understanding of how voltage regs work - how capacitors work ..etc Find out why you need smoothing caps on the input and output stages of a reg, and how the values affect it.

Build up some test circuit of simple things - a voltage reg would be a good start, or a variable voltage reg - test the outputs, stick an led on it or something, get some working knowledge at least.

Rather than starting with a big complex system that you have no idea about, and getting frustrated when you can't fault find.

Why do you think two voltage regs inline is going to be better than one? A voltage regulator either regulates the output voltage or it doesn't.

Have you asked on the Arduino forum? Going to be lots of knowledge people on their and support.

Ok...still dont know what a smoothing cap is.

Dont know what a IC is either

Ruans suggestion to help with the poor electrics in my french shed was a 12v then to 9v and a seperate reg system for the sensors, so 12v then to a 5v. Cleaning up the 12vs as i understood it.
Pointless or not, they are in there!