The circuit is based on applICation of National SEMIconductor. First is constituted by three voltage regulators LM338 [IC1-2-3] connected `"in parallel" ". The each one regulator has the possibility of giving 5 The in the output becomes the output voltage from +4.5V until 25V DC, stabilized. The voltage regulation in the output becomes with the TR1. If it does not exist the need of this continuous output voltage regulation, then We CAN measure the resistance value of trimmer TR1 in the particular output voltage and him replace with proportional value constant resistance. The Rectifier Bridge BR1 should be placed in some point of metal box so that it"s frozen. On the contrary the IC1-2 -3, that good are is TO-3 case, should be placed in a capable dimensions heatsink, with planning mica isolation between them and the heatsink. Also it should sort-circuit in no point with heatsink. Resistors R1-2-3 should Be placed in some distance from the PCB in which make the circuit, because are hot and exists the danger to burn the printed board in that point. A point that should it"s given attention they are the cables from where it passes big current, It's big diameter, as we Ll and the output plug of suitable type and fine placement so that does not exist the case of short-circuit. In the second part of drawing exists a simpler circuit that is based on the voltage regulator LM350 which has the possibility of giving in the exit The regulated voltage from +1.25V until 25V Dc and biggest current 3 A. Good is the IC5 are in case the TO-3 for better thermic conduct and it"s placed on heatsink [with essential mica between this and heatsink]. In the output becomes with the trimmer TR2. The the circuit is supplied from the power transformer bigger than 450VA. The manufacture of circuit should become in the suitable dimension box that should ventilate well. In the expulsion of temperature can help a fan 12X12cm working in 230Vac. In the outputs you can place Voltmeter and Ambermeter.
R1-2-3=0.1R 5W C3-5-8-10=100nF 100V MKT IC1-2-3= LM338 [TO-3 case] on Heatsink R4=100R 0.5W C4=220pF 100V ceramic IC4= LM308 R5= 150R 0.5W C6-11=47uF 63V IC5= LM350 [TO-220 or TO-3 case] on Heatsink R6-8=330R 0.5W C7=4700uF 63V J1=3 terminal bLOCk computer type R7-9=4K7 0.5W C9 =10uF 40V J2-3-4-5=2PIN Connector 3.96mm step pin R10-13=1K5 0.5W D1-2=LED Red 5mm F1=Fuse 5A slow block R11-12=220R 0.5W D3=1N4007 T1=230Vac /22Vac 600VA transformer TR1=1K5 trimmer BR1=Bridge Rectifier >250V 35A on HeatsinkSymbols
TR2=4K7 trimmer BR2=Bridge Rectifier >250V 3A uF=microfarand, R=ohms, K=Kilohms C-2=10000uF 63V Q1= 2N2905Active Stylus Pen,Stylus Pencil,Capacitive Stylus Pen,Tablet Pencil
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