 So the BC546s which I was waiting for have arrived. They arrived very shortly after uploading the first part of this video. Now I did some game checks and you can see the numbers there. So I pulled out the closest numbers, four of them, two 313s. I put the 314 there and 315 there. So that's it I pushed on with that. The 3.3 half watt resistors I've decided to use 2.6s and just put them parallel to each other because these are quarter watts so we've got a half watt dissipation. I've made sure there's a gap between them as well. You can see that gap just to help with the heat dissipation. So I'm going to carry on building this now and get on the next section which is going to be this driver here for this side. Then I'm just going to put some power line expression on. So I'm going to get cracked on with that and of course I'm going to make sure I put this boot strapping. So I'll crack on with that and let's see what it offers. First of all I'm going to clean up all the circuitry underneath here and cut it to the right size and solder and where I can get myself worked up to this stage before I start putting the next lot on. Okay well I've got this far and although it looks more done than what it is, these are not soldered and these are not soldered. So everything else is pretty much there. I've just got to figure all this out again mentally because there's still a little bit of a couple of capacitors to put at the sides here or where I can get them in for this ground. Not quite sure that's exactly where these are going to go. I'm trying to keep everything in my mind and I've just managed to boil my kettle dry and kill that. I don't know why I didn't put the lid down but at least I didn't do what I normally do which is burn my dinners. That's why I always cook everything in the oven though. I'm sick of going into my kitchen with the pans on fire near enough, smoke coming out everywhere. But if that fits down there and it will go on there, that's not looking too bad because then all I've got to do is insulate, give it a heat sink and then it's crack on. So well I've got it pretty much all soldered, apart from that green 100 nanofarads that's not soldered. So I've just got to try and work out how I'm actually going to do that. So I've got to put two 100 nanofarads in series. I've got to put a 100 microfarad between the connection between the 200 nanofarads and coming down to ground. And I've also got to put a 10R resistor between the 100 nanofarads and this side of these two resistors. So I've got a little bit of gymnastics to do there with the wiring but I've got to do a little bit of gymnastics on the back anyway as you can see. Really doing it with those transistors the way they are is probably not the best way but the web page for the circuit does say to use their board. That's not terribly too bad. Now I'm going to do that so I'm going to leave it. I'm going to set it to one side because I don't want to connect these in until I've really planned about how I'm going to do this 10R here. As you can see look this is all after these resistors. So I've just got a little thing about that because that's going to be clumped to the back of that. So everything's really got to be this side and then just white underneath. I'm going to leave it for a little while now because I really want a cup of tea or coffee and of course I've killed my kettle so it's a saucepan job and I've got to watch that because I know I'm like I'll come in here and start playing with this and it's like 40 minutes later I'll go out and find my saucepan completely burnt, hell and welded to the top of the cookout. And of course giving it a break means I can come back go over it again and probably have a bit of a refreshed idea of how I'm going to set this out. They're so far so good. Okay so there it is. Pretty much ready to go. The output connector is here, the positive and the negative is here. You can hardly really see it. Wait it is all the minute. Where's my little pointy thing? Have you got any pointy thing? I use this. So here, where am I? There we go. This here is that and this one here. Oh just here. This is the negative for the output. I'll go over it again. Look it again tomorrow in the light of day. I'm not going to connect up now. I'm just going to enjoy a well deserved beer and go over all the connections tomorrow. Check, double check, triple check and then put the heat sink, heat heater, heat sinks on. I'm just going to clamp a couple of small heat sinks to them. As long as they've got heat sinks, just back that out. I'm just going to clamp a couple of small ones just to check it. We're going to put some fuses in. I'm going to set up a little bit of things so it's got fuses and everything just to do some tests. On the documentation it's got a whole bunch of tests. Well not a whole bunch. There's a couple of checks got to get this quiescent current down here. Make sure that's set all the way to the maximum resistance. If I read that correctly. But wait until tomorrow and I'll bring it over here. Right guys, here's the scary bit for this. I'm going to try and test this out first. I've set up the 35 volt. Yeah, no, is that right? 25 volts to 35 volts. Yeah, we can get the maximum of that, right? 35 volts per channel, per rail. So we've got a positive rail and we've got the negative rail. And this is the fingers. No, not weird in real life. Weird in the camera. So I'm going to use a pointy pin. And we've got the negatives. Now I've put some 22R 5 watt resistors on here because it tells me to do some checks. Because what we don't want to do is, I haven't got a dual power. You know, this is something I'm actually missing now. These are the dual power supplied, isn't I? So I could, I could have run this voltage up slowly and just checked for using too much current. And I don't know, I was smelt wrong somewhere. But this way what I got to do is just basically connect this to here and that to there. So here's the ground connections. Anyway, these brown ones, I took it off the last one and just added another wire. It's pretty much the same, but it is the same sort of setup, isn't it? But revised and hopefully much better. So this is the output positive. This is the output negative. And if these two touches just going to blow those output transistors, we don't want that to happen. Just like on the old circuit on this one, there's no output protection. So if you short the output, you can say goodbye to your, these ones aren't that expensive. But the ones that I'm going to buy are pretty expensive. You'd be able to say goodbye to those chips. I've got to try and get this quiescent current using this trim pot down to 20 milliamps. I'm not exactly sure how long they're there to do that. I'm not sure how you know measure it. So the whole idea is to get it down to 20 milliamps. So I need to just do some more nose and to see exactly how I'm going to be measuring this. So I know when I am on the 20 milliamps, it's all great. It's saying get it to 20 milliamps. But how I know using the pot. Yeah. But how do I measure it? How do I measure it? That's the thing. So and then these are the only two heat sinks I can use for now. But they'll be all right. I'm going to try and crank this thing up or anything. You can't crank it up anyway when those resistors are there because it would just, they're acting like fuses but they're not fuses. I mean the fuses would just pop pretty much and these would just get hot and something on here would get hot and I just know to quickly disconnect it all and then we'll see where we go from there. So this is the scary bit to be honest with you. This is the scary bit. I can't put a load on it. I'm going to be careful because I've got audiophile cables. Let me see there which means there's going to be some sort of passive load on there as well. And we'll get so complicated. I remember the days when I just go to a shop and buy one of these things. I was sitting there and I build one. So it's so far so good. It seems to be okay. I'll show you underneath once we've tested it and it hasn't blown up. Just because it's going to be hard to, oh no it's not going to be hard to turn it over like this. There's the underneath look. It's not a big horrible mess but the layout of it could have probably been a bit better. But this is the first go. I'm just sitting it on here so I'm not particularly that worried. I don't expect it to be to the spec from here. That's enough for me Gibby. Now what we want to do is see what happens when you put some power to this. So let me just figure out how I'm going to get these connected to this. I need to find a couple of little connector things but I'm going to put them on here and just shove those into the hole so I can quickly whip this out if I need to because that's what we want. Okay so let's just turn this on up there and we can have a little look at what the voltage is we've got coming out on. What's going on with this? Why does it look like I'm in the sunshine? What's going on with that? It's weird. Can you see down there? I just want to be able to see smoke. That's what I want to be able to see smoke and smoke is going to happen. So let's just do a voltage check on this output first. It should be around about 70 volts or 35 volts per channel. It doesn't really matter which amount I put these on here. That's going to prove to be a bit awkward so let me just put that. It's going to be a minus that we have on the display. This is minus 48 at the minute and that's because that's not been down. So there we go. Okay so that's 70 volts okay and that's what we want. 35 volts per channel so now I'm going to connect in these two resistors but I'm not going to put the power back down. I'm just going to see if anything happens and toward when I'm connecting the two resistors. I did notice I'm sorry you didn't get to see it but the little green light came on the LED came on. When I first connected into this I presume it's because it just sucked out the last bit of juice out of it but nothing. Not that I'd be able to tell them anyway but one thing they do now is I'm just going to put the power on. Hopefully that's all when they're pressed in there good enough. I'm going to put the power on and just see what happens. Okay so we got green light that's not just a bad thing. I'm going to take the power off for a second and just check. Just check that nothing's just gone really hot at all. Any of these transistors? Let's just get my finger onto this one. It doesn't seem to be any heat. So let me just put that back down there again. Just leave it a little bit longer this time. Fingers on these. Nothing. Nothing. Power transistors. Nothing. I can see smoke. I can see smoke. That's not a good sign. That is not a good sign. That is not a good sign. That is not a good sign. No. Okay so there's a problem somewhere. Now these resistors I supposed to get a little bit warm but they are very warm. That's a bit too warm. The wire's okay but the resistor and that resistor is very warm as well. There's a good possibility. See none of this is warm. None of these transistors are warm but those two resistors those these two resistors are very warm. They're very warm indeed. No I don't know how long I can leave that connected like that. I'll be very careful with these. I was going to do reading on the output of those but obviously if it's going to be getting too warm there's something I missed. There's something I missed. I'm not quite sure what it is. Right then I'll have to have a little nose and feel about on the bottom. Bottom of the circuit not mine. Right well none of the transistors are getting hot. These two are getting pretty hot. The supply voltage is 35 volts per side. These are getting hot but nothing else is. Nothing on the bottom of the board is getting hot. None of the components are getting hot. Nothing is. So I wonder why that's doing that. Now I know that I should check the quiescent current by getting the voltage reading between here and yeah I'm going to have to sort of like go over this and go over it again and just do a check but at the minute because the way it is like everything's upside down on the wrong way around so it'll probably be easy if I get it all turned back around the other way again. It's just that I need to shift this and pull it around so it'll come around the other side because I've got on the power supply this side because all that stuff's here and but really I need this over this side and put this here so I can keep it the right way up at least. Right well because of the bits before this and because of this bit this is going to be another sort of 10 minutes so I'm going to put this up and give myself another bit of time to look over this. It's a little sour of the power but these these do get warm quite quickly but the wires don't get warm. These do and underneath on the board it doesn't get warm. Nothing gets warm. There's no change in temperature on anything. These are actually cold, cold to touch. Nothing gets warm on here and the little green LED still works so there's nothing else that's quite good yeah. Let's just do a check actually. Let's see if that is still working. It says that we're really supposed to have a bolt on there but we've got more than a bolt as you can see. The light doesn't work. Trying to see if they might go. It's slightly off warm that is slightly that one is a bit colder in this one. This one's got a little bit more warmth on it. Yeah just need to go go through it again so this is going to be a three a three a three stage thing at least my looks a bit. Yeah and I'm gonna come back when I've got something and I figured this out. So I'll see you in the next one.