Ok so guys I'm muhammed from south africa, I have a 400watt star sound amp,and a 45wx4 sony radio all running in my workshop...I used to run them of a 1970s 50amp ac-dc transformer but unfortunately she burnt out trying to test a starter! So now here is my problem I got a 638 12volt car (lead acid) battery to run my amp and radio (it lasts for a full day) and I have a 15amp transformer to charging, now I need to build a rectifier and a regulator so it does not over charge for this project. I mean its only for charging and not for testing starters!SO ANY IDEAS GUYS? If you'l got bbm you can invite me