lz1jer, даде този линк, който е с подобна идея за зарядно:
http://www.aaroncake.net/circuits/charger2.aspR1, R3 2 330 Ohm 1/4W Resistor
R2 1 100 Ohm 1/4W Pot
R4, R5, R7, R8 4 82 Ohm 2W Resistor
R6 1 100 Ohm 1/4W Resistor
R9 1 1K 1/4W Resistor
C1 1 220uF 25V Electrolytic Capacitor
D1 1 P600 Diode Any 50V 5A or greater rectifier diode
D2 1 1N4004 Diode 1N4002, 1N4007
D3 1 5.6V Zener Diode
D4 1 LED (Red, Green or Yellow)
Q1 1 BT136 TRIAC
Q2 1 BRX49 SCR
T1 1 12V 4A Transformer See Notes
F1 1 3A Fuse
S1 1 SPST Switch, 120VAC 5A
MISC 1 Wire, Board, Heatsink For U1, Case, Binding Posts or Alligator Clips For Output, Fuse Holder