What you have is an RCA built ac/dc set. The 3 prong
is for a battery pack. The 4 prong is for AC or DC 12V.
Get it wrong & you see fire engines.........
If you can get the KCS*** number I can look it up &
see which pins are for AC if I got the manual.
Number may be on back but IS on the chassis.
73 Zeno
