12v Regulator Schematic (15A)

12v Regulator Schematic (15A)

 Well I dont know much about electronics so I asked a friend of mine to make me a 12v regulator. Please do not ask me about it since I have no idea about those kind of things. However, I wasn't able to find a decent schematic of a 12v regulator so here it is. The Voltage on the car must be over 12.8 to supply a regulated 12V but the nice thing is that it is 15A and with a fuse can be lowered to 5A. He said that the components are cheap and not hard to find. He uses a so called "zener" which I havent got any idea what it is!

I am interested in your comments since you know more about this stuff. I know this isnt the BEST regulator available but it is a simple solution that I wanted to find and never did. Hope that it will be usefull to you all.

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 Thank you