Hi Eddie, Great video, really informative - I like how you go through the data sheets and measurements on the meters/scope. Got a few questions: 1) When you were doing the maths in your book, you used P = v^2 / R but in the on-screen notes at 29:25 you have P= V^2 * R. I'm assuming it's the former - in fact, I'm pretty sure it's the former, and your calculation (almost) bears that out: but, 33.8^2 / 8 = 142.81W not 143.23W so did you have slightly different figures in the end? 2) I must have missed it, but where did 8 ohms come from - is that just an example 'load' for calculation purposes? Really looking forward to that optimisation video. I'm starting to pull together my input power stage for my supply so it'll be really useful to compare what you say with what I've scratched my head and come up with! Incidentally, I don't think my cap bank is bigger than yours - 80,000uF is one bad-boy smoothing bank :)
Thank you! Yes, good catch, that is a mistake on the second equation. ;) I used 8 ohs as a speaker load. The differences are probably rounding errors, or a typo;)
WOW FANTASTIC, THANKS!! i AM SO HAPPY!! THANKS!!:-) I'll contact you:-) Finally a really quality meter, instead of my cheap meter! :-) Really great video, thanks for going so detailed trough the setup, that helped me a lot! I do also like that you put the calculation on the screen, wary informative:-) In your circuit drawing with a center lead, you only used 2 diodes, but here you are using 2 in one package, would a single shutkey diode per side not be enough? Can you please tell me the name of the gray-orange thingy you use to connect the cables with?
Fried Mule Congrats!!🎈 Yes, a single diode will work great! Actually, I’m not confident in parallel diodes sharing very well. That subject is worth a video! I’ll get a link and part number for those terminal blocks - very handy and reliable parts.
Fried Mule Congrats!!🎈 Yes, a single diode will work great! Actually, I’m not confident in parallel diodes sharing very well. That subject is worth a video! I’ll get a link and part number for those terminal blocks - very handy and reliable parts.
Fried Mule Congrats!!🎈 Yes, a single diode will work great! Actually, I’m not confident in parallel diodes sharing very well. That subject is worth a video! I’ll get a link and part number for those terminal blocks - very handy and reliable parts.
The grey/orange thingies are Wago clamps - www.wago.ltd.uk/connectors/lever/ They are well liked and you can pick them up off ebay, amazon, screw fix etc etc
Just to be sure, I did send you a mail yesterday, but I am not sure if I did write the right address? :-) I am not in any hurrie, would just make sure, so please take it easy and good time! :-)
I may have an idea to a more advanced video:-) I have read about different transformers, EI, Toriodal, O-Core, R-Core and others and everyone have there opinion. But What are the difference, where are one core better then an other? Flux, saturation, heat and so on. :-) I.e. have I heard that O-Core are better then toriodal because the O-core is rounder in both direction and therefore less noisy. The R-Core should be the absolute best, because you avoid the copper being pressed more together in the inner diameter then the outer of the ring.
Couple of questions .... 1) What purpose is served by the little capacitors on the output? 2) How does a diode and resistor in parallel with the output limit the current? Great video!!
Thanks Victor! Great questions! I think the small caps that you are referring to are for low impedance at high frequencies. I’m not sure what diode and resistor it is that you are referring to.
@@KissAnalog Oh, I get it. The LED is just to indicate the circuit is live. When you said "limit the current" you meant the the resistor ws limiting the current to the led. I thought you meant something else. I got knocked on the head a couple weeks ago and I am still learning the basics.
Hi Eddie, So the normal equation for the ripple needs changing ? Example I load / (2* frequency * capacitance in Farads) = the worst case ripple voltage expected This is now I load / (4* frequency * capacitance in Farads) = the actual ripple voltage expected. As your demonstration on the scope ? Sorry if I ask to many questions 😉 Adam
Great question! Please keep them coming - you hit on key points. The more conversation, the more others will learn;) I think it doesn’t quite half the time again as the charge time is not equal to the discharge, and actually gets to be a lesser percentage as the capacitor size gets bigger. Maybe reduce the time by 20%?
I have a question for you about choosing the right size of transformer. Would it be possible to use a DC lab power supply and then drive the music amplifier as hard as possible and adjust the voltage on the power supply until there are minimal amplifier distortion, then read ampere and voltage and get a transformer that fits these values?
Yes, that’s great insight in how one might choose the correct voltage. After my videos in showing the types of distortion, I plan to start reviewing these Amplifier boards, and I want to demonstrate how a particular voltage might be chosen for optimal performance, or for max power. I think the class D amps are bringing about an unexpected challenge...
@@KissAnalog Great, that's only because your videos that I am beginning to get enough knowledge to add 2 and 2 together:-) I am looking wary much forward to your class D videos, I have heard so much bad about them for audio but I also know that some high end amplifiers are fitted with class D. I can imagine that it is not as easy, things are not so simple in electronic. :-)
Thank you - I appreciate that! I’m also very interested in the Class D, and actually had high hopes, but the little I’ve worked with them...I’m not so sure now. They do definitely shrink the size of the amp and are able to put out much higher power because of their high efficiency - which also lowers the cost. But! To what cost? I have a bunch of boards - including a ‘high-end’ and higher power one, so we will find out if they get Kiss approved;)
hi Eddie, I appreciate for your contribution on electronics world, i have a question i have an amplifier on my bench which should operate 55-0-55 8amps unfortunately it is hard to find it and to make the amplifier works. can I use DC power supply to this amplifier????
Good video Eddie, Congratulations to Fried mule 😀😀 Please take my name out of the draw please. I have more than enough kit, Also shipping would cost a fortune. Maybe somebody else that doesn't have good test equipment, will appreciate the meter. Cheers Adam
Adam L That is very gracious of you! I’ll be clearing out my storage where I might have something of interest, and I’ll have kits available after my review, so who knows? Also, Yorkshire isn’t too far for a great supporter of this channel!! ;)
@@KissAnalog I appreciate your time to share your knowledge. That's more than enough, with out you incurring expenses on shipping 😉 I've realised how much effort it takes for producing a YT video now. Keep up the good work ATB Adam
@@friedmule5403 Your welcome, I'm glad you'll probably make good use of it. I know its expensive justifying buying equipment especially for a hobby 😉 Good on Eddie for the great give away😁😁😁 ATB Adam
Thanks for the great question! No, having a 'stiffer' output DC voltage rail due to adding more bulk capacitors will not hurt your amplifier. As you say - as long as your circuitry feeding the caps isn't hurt by the larger inrush current.
I’ve got a 240v/24v 200w toroidal transformer I want to put a 24v DC submersible pump on for my aquaponics project . I understand there would need a bridge rectifier, deciding on what size capacitor is what is troubling me . I’ve been told there would be a need for a 1000uf capacitor. 24v (?)
Great question Martin! I'd say that 1000uF cap would probably be OK, but then it depends on how much voltage ripple is OK. With a motor, I think it would be ok with some voltage ripple. You could start with 1000uF and go up if it didn't seem to run smoothly. It wouldn't hurt to go 3 or even 10 x larger. Now, remember to get a capacitor rated at a voltage higher than the 24V. It would probably be great to have 50V rating (possibly 35V).
@@KissAnalog , the pump I’ve got is 24v180w , hopefully it won’t get too hot in there . The transformer is in an enclosed , waterproof container , metal bow with a plexiglass cover .
@@KissAnalog , well , it went BANG . I left it run for two minutes and I thought I was on a winner (first time wiring) . I had bought a 25v 1000uf capacitor . Not enough apparently. I live out of town so will get another capacitor to have another go .
@@martinbonner8626 A little late to this rodeo, but yes, your capacitor would go BANG! It was only rated at 25 volt and you said your Transformer gives 24 volt. That gave you a 1 volt margin of safety without the capacitor. When the capacitor was added, that 24v went up over 30v without any form of a voltage regulator to calm it back down. (Give or take some losses with the bridge rectifier) So having a capacitor only rated for 25 volts now pushing over 30 is going to destroy it. As said, a rating of 35v would be barely squeaking by, but getting one rated for 50v would be much safer.
