12v battery charger

Hi all, I'm looking for info or schematic for a Tenatronics 12v 10A battery charger. I realize that these are not usually repaired, just discarded and replaced with another cheapie.
I am into electronics on a hobby level and on this unit I replaced the 2 MOSFETS ( 1 of which was bad) and it tried to charge( slightly flucuating needle) and then no charge. I have not rechecked components yet,but would like to find a schematic first. The board is Tenatronics#50-115 and unit serial is 642343 B. It's a 12V 10A unit and I'd like to learn more about its operation. Thanks for any info Cooter

Probably not quite what you're looking for but, look into a CB "powerpump". It's a converter - from 110v. AC to 12 - 14 v. DC. > made for operating a mobile CB as an in-house base station. - - Can be used as a trickle-charger / might be 'modified' for more amps output.

Hey thanks for the idea, I'll check into that. I'd still like to get a schematic for this unit to assist in trouble shooting.