 Okay, well, today I've got a bit of a mission on. The power supply you see before you has a bit of a fault. On the left channel, the negative is shorting with the Earth. I'm going to circuit there on the right channel. It doesn't work like that and it's not supposed to work like that. So today I've got to pull it apart and figure out what's wrong. But before I can do any of that, I have to tidy up this bench because it is a mess. It is a mess from lots of prattling around. A little amplifier circuit, another little amplifier circuit playing around with the old air. Jacob's led last night as well. Got a little ZVS driver to fix there. Diodes gone on it and even now it's there with that. Fixed this little power supply up. We've got a couple of blank components. Okay, so I'm taking the screws out of this thing. What I'm going to do is take it close here. Zoom in. There's a couple of capacitors there, 100 nanofarads and that's what I've been told to look at. This is the image they sent me. I'm going to zoom back out and I'm just going to try and move it a bit closer with the camera. Slide round the large screen. So as you can see there's an electrolytic there on the left and some plastic, some poly, poly, poly, poly, poly, propylene type film, jubbys. Those two there are the ones I've got to check because if they're shorted, if they're short, then there's a possibility that that's what's causing my grounds to negative connection or at least on the one side there. And this is the engineers I told them what was happening with it. They've actually sent me the wrong side. From this we're looking at it at the right hand side because if I'm not wrong, bottom left of that picture is a multi-turned part, which would indicate the voltage control on the right hand side of the supply, where really I want this board, but on the other side. Yeah, yeah. This is the second power supply, the second of these power supplies, the first one which short out when you put it in parallel mode or serial mode, which is no good as I need the 10 amps sometimes. So instead of this one going back, they've just got their engineers on the picture of the capacitors that maybe have failed. And I've got to go in and figure that out. Yeah, so here we are. So this is the mission this afternoon. Let's get in here. I'm going to take this off and pull it forward because these boards are here. The actual back of the board on the photo, on the screen there, is this side because there's the pot and it's quite a big unit because in the back here. And it's actually this side where the earth is connected to the negative and I don't want that. I don't mind having it as an option, but I don't want it. So that's what we're going to do. So I'm going to take the case off and we're going to take a look at the inside. After taking a peek in the back here, I'm actually wrong. The image there is off the correct side. What you've got to do is just position yourself upside down. So the fellow got in here upside down and took the picture and sent it to me. So all we've got to do is undo these screws. It's the same on the other side and I'm pretty much hoping that that's just going to drop forward without too much ado. Well there's the... that's disconnected. You see I can't get down there with a multimeter. Well I think even if I zoom in, you see the capacitors down there, that's where I want to be. I don't think that's what I think you can see them as they're right down the bottom there. So I'm just going to turn this over and do the bottom screw so I can just move the returner's over the whole thing. The best thing while you're staring in the half kilos, I mean look at the size of those. Those transfers, not that you get to see them. Sorry I really don't know that side but you get to see the side there so. And it's down here and I'm going to get to see just inside there in the middle. The whole picture's gone a bit shh go away. So yeah, not the easiest. But then it's definitely not the hardest to get to either. OK well I've turned the unit round. There's one of the capacitors, two of the capacitors there look, the two green ones. That's what we've got to get to. So I'm hoping I can get in here now with the probes and as far as I know there's supposed to be two 100 nanos which I've got plenty of spares if they have gone. One of them's gone. Not too bad for this. The way it's put together. It does say on the advert that it's all SMD which, well maybe they've redefined SMD. But there are some SMD. You know we've got some, and it's pretty modular as well. So if something fails, I don't think that's not too bad. I can just take a part out and see if you can get it swapped out. Nice multi-turn pots. The capacitors, they're then cheap crappy Chinese jobbies aren't they? Maybe I could swap them out for some Rubycons or something. But they are the cheap Chinese ones. But how do I know that if you just look at them? You've got loads of these things, loads. You get like 30 billion of them for £3 if you send it off to China. And they just keep bombarding you full of their capacitors. But anyway, well I could be wrong. I could be wrong. The vent on the top looks a little bit different to someone. But right, so I'm going to see what else for this. I've got to pull apart to get my probes in there and find out what's going on with those caps. I'm going to use this puppy for measuring. Even though they're really good. And they are, they've actually got hardly any resistance at all these. I can't remember what it is, but it's really low. They're going to be harder for me to get in. Then using some of these ones, because I can take the ends off there and have nice, you know, long db bits to nice prongs to poke in there. So, okay. Right. And the old brimer, which this does work quite well. I like this. It's a nice little bit of kit. So I'm just going to have to try and see if I can do this. I don't think I'm going to be able to do this with one hand. I could normally chop stick it, but because they're, maybe if I swap hands, I'm going to try and do it with my left hand. No, I'm going to have a problem with this. Hang tight. It's not as easy to get to these as what I thought. The top one there, this one thinks it's a resistor of 500 megs. This one down here has a capacitance of 208 nanofarys. These are supposed to be 100 nanofarys each. That's only what these are. So, I've got a funny fear in that these are not very good. But really, I have to take them off the board, unless I can get in there. The way these have been pushed in, that I can't actually get a probe onto there properly, I'm going to see if I can get into the mesh, see if I can. So, well, it looks like the side that's working okay. The two capacitors here, both of them measure 208 nanofarys. They're 100 nanofarys each. And the capacitors here, well, the top one, this one, that measures a short OL on the capacitor. They've got the continuity, just a few irons. Resistance, and the one down at the bottom measures 1.2 millifarys. So, I'm not quite sure how that's been affected by the other one being short. I'm not going to screen on this screen here. That's where we are. C1, C2 is short. C1 is measuring 1.2 millifarys. As far as I know, that's a 390 micro is fine. But, yeah, see what we've got is there's a connection between ground and air for short. Mi continuity, you know. We don't really wish for that. On the other side, you can just pull this back slightly. Now, on this side, this is a presume output 2, board 2. Let's see if the siding over right-hand side is a secondary output. That should all be exactly the same. But, like I say, both of those capacitors there measure to 208 nanofarys. And that side is fine. There's no connection between short, negative, and ground, which is the way I want it, you know, floating, rather than have mains reference air running through the ground, the negative connections. So, I need to write an email now, just sending that back to the engineer, circuit specialists, and see what they say about that. I wonder if they're actually going to compensate me for my time. And, of course, it hasn't finished yet, because we, let's spin round here, if I do, if I am asked, because I've got spare capacitors, I've checked, I've got loads of 100 nanofarys, these film capacitors. If I do have to, look, I'm going to have to unbolt the connections, unscrew all this, and hopefully leave all the wires connected. But I'll have to unbolt from the connector lead terminal. Connectors, so I can then pull this forward to be able to desolder, of course, and replace those capacitors. You know, I mean, this isn't terribly great, but then it's not terribly bad either. These are some chunky old, chunky transformers here. So I'm going to turn this about so it's how it should normally be sat, because I don't like the idea that it's putting a lot of strain on these screws, and on these components. So there we are, about turned. Feel a lot happier with it like that. But as you can see, look, all these will have to be undone. This is one, two. I can't tell what's on the inside of there, but there's three screws. Six bolts, and that's even to be taken off. And as long as that is just it, hopefully then that board will come out, and I can change it. And I think that's what I'm going to probably do now. Actually, I may as well get on and do it, because I've got a funny feeling that they're not going to pick this supply up. They're just going to leave me to fix it. It won't be the first time that's happened with what I bought off eBay. I've got another power supply here, which I have to fix. Another 10 amp board as well. So I'll probably have to do this one as well. But you know, it's really painful when you're going by stuff and you get it at home and you've got to fix it before you can use it as you want to, or if you should be able to. I just noticed down there, I don't know if you can see that, but that's a target. The red wire is all coming out that blue sleeve. That's a target little there. There's some rain wires coming out down there. You can see the big ass diodes and stuff. I'm not sure what you can see when I put the light over like that because it actually blurs out the picture on the screen, so I can't see anything. Which that probably doesn't help, because I tend to have the brightness dimmed out on the screen. I always take the phone into bed with me so I can watch comedies. I just fall asleep laughing at comedies. So, yeah. I suppose I better start undoing those and pulling that out.