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Simple NPN switching circuit to open a relay circuit, first NPN switching part didn't want to work (3rd PCB and endless times of trying).

Circuit wizard diagrams, I split its first part to figure out the problem, then removed the push button to ease it even more:

(Note top view of components below has been photographically mirrored)

Solution by @ Andy aka: I had short circuit at all resistances.

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Does your regulator heat up when the relay is not energized? A regulator like that is simply a controlled power resistor, so if the relay draws moderate current dropping that current through a resistor from 9v to 5v will produce substantial heat. You can add a heatsink to the regulator package (it is designed with that in mind) but it would be better to use a battery voltage appropriate to the relay and skip the regulator. Also, a 9v "transistor" battery is a poor choice for this, as it will have a short lifetime. –  Chris Stratton Mar 21 at 14:31
    
The fuzzy photos don't help. Are your schematics correct, and which one did you actually construct? Is the relay part of the circuit when the regulator overheats? –  Joe Hass Mar 21 at 14:33
    
Additionally, that regulator requires a small capacitor across its output, and possibly across its input as well, in order to function properly. Leaving that out can lead to instability, or even outright wrong voltage. –  Chris Stratton Mar 21 at 14:33
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Also, you should put a diode across the relay coil, reverse polarity of the LED. My guess it it's simply heating up because you have a low resistance relay coil. What is that resistance? –  Spehro Pefhany Mar 21 at 14:46
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It's probably the photo but the tracks don't look like they're cut beneath the resistors. –  Andy aka Mar 21 at 15:04
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2 Answers 2

up vote 16 down vote accepted

Shouldn't the tracks be cut under the resistors: -

enter image description here

I've put a label on the picture but the track doesn't seem to be cut anywhere. Maybe it's my eyes?

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no it's one long tracks along the pcb –  AndrewxXx Mar 21 at 16:00
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Then the copper tracks are shorting out the resistors dude. You need to cut tracks beneath resistors that have both pins on one track. –  Andy aka Mar 21 at 16:08
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@AndrewxXx: He isn't saying "shouldn't it have come from the factory cut already?", he's saying "why haven't you cut the tracks so that the board matches the schematic?". –  Ignacio Vazquez-Abrams Mar 21 at 16:24
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@AndrewxXx If you want to avoid cutting tracks then you can place the components vertically, from one strip(track) to the other and each track represent a node. –  alexan_e Mar 21 at 16:33
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Sometimes the most obvious stuff is the hardest to see. –  gsills Mar 21 at 16:51
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Regulator looks mirrored on the photo.

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That looks like a good observation to me +1 –  Andy aka Mar 21 at 15:02
    
i did try to reverse it even that i know it should be like this from the data sheet but ill try to reverse it again, here is how it is now resistorworld.com.au/image/cache/data/4e73_1-500x500.jpg and it output 300 hfe like in the datasheet on the avo, but ill try that "again" –  AndrewxXx Mar 21 at 15:02
    
That is a transistor... Not the regulator –  Dejvid_no1 Mar 21 at 15:04
    
There you go: www.fairchildsemi.com/ds/LM/LM7805.pdf‎ –  Dejvid_no1 Mar 21 at 15:05
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But the text looks mirrored on the photo, too. In the original picture i.stack.imgur.com/i5412.jpg neither the regulator nor the text was mirrored. So I don't think this is it. –  Chris Stratton Mar 21 at 15:15
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