this is the circuit! :)

Step 1: The Short Circuit

The protection circuit is activated when a short circuit happens, indicating the red LED andthe voltage down to 0. When you press the push botton resets the circuit! 12v

Step 2:

you need:

-power transformer 120v AC/18-16-12v DC 1amp.
-bridge rectifier
-(2) leds
-resistor: (3) 2.2k, (2) 1k, 0.5, 10k.
-capasitor: 2200mf/25v, 100mf 25v, (2) 47mf/v.
-diode: 1n914
-diode zener 18v
-push botton
-resistor variable: 5k
-bc178, bc549
-bd135 and 2n3055

all the components are shown in the circuit diagram.
<p>i have a variable power suply with lm338k and need a short circuit proteccion you have this only schematic ?? thnx</p>
<p>would you explain the theory of operation ?</p><p>Thanks.</p>
<p>would you explain the theory of operation ?</p><p>Thanks.</p>
<p>Looks great. Can I attach more 2N3055 transistors to increase output current?</p>
ooohh! ok thanks! <br>
yes, is right. can you tell me which program did you use for the schematic? thanks!
He used <a href="http://www.cadsoftusa.com/eagle-pcb-design-software/product-overview/?language=en" rel="nofollow">Cadsoft EAGLE</a> for the schematic.
Please check my schematic and make sure I read yours right. Thanks.<br> <br> <a href="http://i.imgur.com/o7yah.png" rel="nofollow">http://i.imgur.com/o7yah.png</a>

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