 Hi guys, here's an interesting little circuit, I'm using an external power source, about 11.5 volts coming from that power supply over here and I've got a 7805 on it, a 5 volt regulator and I've got a 5k adjustable resistor there and it's the normal sort of layout for a 5 volt regulator for any of the three pin regulators, the LM 780 series, so what I've done instead of this having to do all the work and be heat sunk, I've put on basically a pass transistor and I've connected this up, I've connected the base of this transistor, which is this to the output pin, before it's final capacitor, I've connected that to the output pin and then on the input pin I've connected that to the collector of this, is that right, so that's my base, so this is my collector and this I'm just checking, but my output pin is connected so here, what it does is instead of the amps or the amperage, the voltage still goes through this regulator, but the amperage sort of, it goes through this instead and this is a two pin 2055 or 3055 sorry, which means it can have a lot more voltage, if I just turn it on and that's a bit bright, that's why I thought, it's just an array of LEDs basically, I did have this on there and I let it pull three amps, but it does tend to get warm, you need to have a heat sink on this, especially if you're trying to pull the sort of amperage this thing will pull, this is a car 55 watt headlamp bulb, so I can really get it going, but it makes it glow red inside, but I've restricted it and of course, like I said, there's no heat sink on here, I'll just pull the wire off and I've already got these little tiny wires as well, they're connecting those together, so basically, you can build yourself a little fixed regulator, you can do this with the LM312 as well, but of course it's a different pinner when that's not done here, this is just for a fixed voltage regulator and I can, because you can put like, I think it was up to like 35 volts or something into this regulator, depending on the power that I put in, depending on how much variation I have on there, but the nice thing about it is you do have a variation and secondly, you can pull to answer it, because this thing I think is up to 15 amps, peak, something like that, 10 amps, and so from what I can understand is really you can have yourself a bit of a 10 amp power supply, so yeah, they call it a pass transistor and that can deal with all your amperage, just got to put a heat sink on it and that's just the setup for the voltage regulator, 7.2 volts, I can adjust that from here, and go down voltage, of course then my amperage I'm using is less than this, you can go back up the voltage, you're limited it to an amp, there we go, I've got no more adjustment left here because that's 11, that's, yeah, because we're going to lose a few volts, maybe 4 volts across the regulator, so I'd have to give it some more input if I wanted to just take it up higher, but yeah, so you can use your standard fixed voltage regulator as a variable regulator, and you can bypass the 1.5 amp limit by pulling a pass transistor on, on the input and on the output and yeah, the emitter side of this just goes to your output, that's what you'd get your load to, collector side goes to the input, where your input power goes in to the regulator, hook on to your collector there as well, and the output of the regulator just hook it onto the base, and you just use your normal ground and the emitter, then you have yourself here a lot more higher powered variable, but fixed voltage regulated power supply, that's all good, cheers for watching!