 Hey there YouTube. This is like a follow-up video from the 60 watt amplifier. This one's somewhat stripped down that I built and although it sort of worked it wasn't very good at all and there wasn't really any information on the website I got it from which was talking electronics now generally when I go to this website most of the things I've built here they work and they work first go and that's great but this seems to have a problem and I understand now that this isn't actually a circuit that's been made by the author of Talking Electronics. This is an old circuit and I think what he was talking about on here was he was talking about the long tail pair and the difference that it makes using that in a circuit and so what I did was rather than just blow this out together because it's quite a simple circuit look at it that's pretty simple rather than just like blow it all together I want to found some more information and found a 30 year later updated version of this circuit which is this one little bit more complex certainly different output transistors and but this is what's considered to be as it can be seen it is not a complex amp but the performance is excellent okay now I'm sure that the performance is excellent on this if it is set out the way that the author has prescribed and he does say that because they build the boards for this so this is a circuit which is he's got a copyright on it but you're allowed to use it not for profitable things so for me building it for this that's fine for me building an amp for myself that's fine but if I was to start selling these and trying to say it was mine that would be wrong so that's not what I'm doing of course all I'm going to do is because on my channel I find circuits on the internet and I build them and fingers crossed hopefully the workers and we get some fun out of it and this is another one of those so I have started to build it and I drew it out here first the reason why I draw it out is because it's okay it's great seeing it there don't get me wrong but drawing it out means I'm just getting more and more familiar with the circuit so as I'm building it I've got more memory to recollect oh I don't remember that being in the correct place um in that place so it's easy for me to go back so I draw it out and it's a little reference to my thing as well this is the amp this is the power supply for it now I've got the parts for the power supply that's not a problem 25 zero 25 transformer I've got lots of capacitance and I've got a nice big old big big redirector fire down here that's not a problem what I do have a problem with is with all these chips because these these are the bd 140s here the 139s now for this circuit I'm going to use those because this is my let's just get it going with what I've got circuit and then I'm putting in I'm putting in an order at the minute um let's just hope that's there yeah putting an order in there with digikey for all the parts because where I normally go which would be far now they don't have these um these particular transistors look they're all rated 350 volts 15 amps on the big power transistors going out and um and four amps on the drivers for them and I need these pots as well 2k precision term parts I also need the um half watt um resistors because there's a couple of 3.3k's here they've got to be half watts here this 10 10 ohm here has got to be a half watt as well and these 2.33s are going to be five watts each um wire wells so that's quite important for this and it's important to have a more same part also just for the sake of um the layout to me starting off layout I've used uh bc 5 uh 457s here um just to enable me just to be positioning on this uh on this board of course I'm not going to be using that when the new one's coming or I may just use it just for this because I got these uh I got some cheap power transistors um which are let me just take you back to this which are the nj w but I think I've got nj l 13 or two they're the same thing it's just out of the package it's slightly different one of them's uh what is it uh hos compliant it was not led for e jubby basically so I've got the cheap ones but these are the ones that are the top ones for this these mgl 4302 and the mgl 4281 which is what I'm ordering from digicom uh digicom it's such a place digicom digikey and that's even though it doesn't actually show you any numbers on there and they're the driver they're just generic so aren't they so that's not very good at all yeah so so that's where we're going to go so this is the next one that you've seen me I'd have built this up or that we speak if I'm going to carry on doing this I may wait until the other parts come in because like I said I need those other resistors I can't just bang this together with anything if I want it to work I can use these cheaper chips I can use the driver chips I've got bd 140 bd 139 that's no problem and I could also use tip 35 tip 36 instead of these just uh just to get it going just uh okay but I'm pretty confident this is going to work now I may end up I may end up getting all the components I need to build this and I may end up just buying the boards the proper board to fit these on that that may end up being what happens because you know I've been looking around I've decided I want to build myself my own discrete amp but not my own design of course because I'm a noob to all this I can't just design this yet there's guys out there building amps 20 30 years experience and running to issues so for me just to be a noob not even two years into this since the contact of me actually doing this to just be able to build an amp I think it's just a bit too far fetch for me at this time but to copy them not for profitable gains of course but just to copy from experience and to help me get familiarized with the components the layouts and all this sort of stuff especially grounding and things like this because it's quite important that you don't make loads of loops and there's more factors at the grounding but I'm not going to go into it too easy to be criticized but we know that there are so yeah so all I can do really is when I get these parts in is finish this off I'm sure I'm gonna do a little something in between that sunlight's coming across quite nicely now but it's blocking out half of what I can see here yeah so I am going to place that order and I'm just going to wait for how long that takes I'm just going to double check again that there's nothing else I need to buy just because it costs 12 pound for delivery or 13 pound for delivery wow they sting you on that you only want a couple of transistors and it costs you a couple of pounds but it's going to cost you a 13 pound on delivery never mind okay so oh yes and these I need to get the bd the bc 546s as it says it needs 546 and the reason why it needs 546 is because you've got the the higher voltages you know I think got an 80 volt collector emitter and another voltage another highest 160 on the air I can't quite remember but there that's what's needed the 546s so I have got some coming and hopefully they're bringing a couple of days but I'm also probably going to put some on the digikey list as well just to well I want to do it I'll probably just buy 10 of the digikey because one I want to see what the difference is between them and the cheap ones I get off ebay see if there's any and it looks any difference and I would prefer to put the better ones if there is a difference between them onto the finished product because like I said I found a v u driver and v u meters which to look at them on the photo look really good but sometimes when you get v u meters it doesn't automatically mean that they're going to be as good as they look on the photo especially depending where they come from and there's some lovely cases out there lovely and collages but it would just be nice to see if I can get this work in the first place I'll get that built up but I'm wondering whether to do this I want it to be a separate power supply so I can plug the power supply into the amplifier to power the amp and then disconnect the power supply when I want to use it for something else I think that's the best way of doing that but I shall return when I've got a bit further with this like I say I'll get these on I'll get the other parts in and and I'll show you this one and if this one's a success of some fingers cross it's going to be if it's nice going to be down to what I'm doing and I'll just have to keep going over and keep going over until I figure it out and then I'll build either using the same sort of layout to two channels onto these type of boards or I may end up buying the proper board from the place that has the circuit and building onto there and then building it into an enclosure and having a nice little nice little but rather powerful amp here all right I'll see you in the next one