If You Want To Repair Class D Amplifiers You Need To Watch This Video!

[@LearnElectronicsRepair]

*This amplifier was repaired on a later video* 🙂 kzbin.info/www/bejne/p6G8amScbLSkhLs kzbin.info/www/bejne/q3y4p3duiLWnetU

[@Lightrunner.]

learning never ends The more you know, the more you have to learn Thx Richard

[@darylmcgee4349]

I am very new to electronics and that was the BEST description of voltage and how an amp drives the speaker I have found. Thanks Mate

[@kalli71]

I'm 50+ and just have this as hobby - I only understood this 2 years ago when I did an experiment I never thought would actually work. I have a dog fence, which is basically an extremely long cable loop (100m in my case) through which a signal is sent that the dog collar picks up when near and alerts. automated lawnmowers work the same way . The cable was broken somewhere and since there is no circuit I cannot measure anything. so in frustration I used my car battery charger (12V and a few amps), attached the minus lead to the garage, which is grounded by a cable into earth from one of the metal posts) and the plus I connected to one end of the wire. I then removed insulation from the cable 50m away from the garage, and used my multimeter to check the cable. the plus on the cabvle and the minus of multimeter I shoved into the earth (into the ground of my lawn) -- and to my amazement I was able to read full 12V ?!?! i screamed with joy (i can now trace the stupid cable), but at the same time I had to sit down as I just understood the concept of it. I _never_ thought that this would work, because there's no cable going back through the ground as such. i was hoping to pick up some residue, a couple of mV difference or so. No. full 12V !!! couldnt believe iot./ I checked the internet high and wide, but noone talks about this simple hack it seems. you also explained it very well in your video. since then for me theres no such thing as plus or minus. just 12V more or less on the other side. Its like you said: its relative

[@glennkingdon5129]

I'm a little behind on the videos, just watched this, my mind is whirling right now. Thanks for the in depth explanations, they really helped me to understand how this amp works. Glad you make it your practice to always use your isolation transformer, or things could have got very spicy. Thanks again for sharing your knowledge and your discoveries with us, so that we can all benefit from and learn from you.

[@robtitheridge9708]

in the last 3 years i have had to learn a lot about class D amps be cause people keep bringing me low end car power amps . i think ther you tube chanel barevids and of coarse your own chanel have been a great help

[@pieteboe]

again i learned something today , i repair stuff from when i was a child. basics is everything i now understand. ty teacher.. say hi to your wife from me , greetings from Eindhoven (the Netherlands) , ps .. ur funny

[@Tims_Projects]

I didn't know much about amplifiers until I came here, I thought H-Bridge circuit was for motors, But makes sense now for Amplifiers. Currently working on a new motor driver, for my robots. Burnt a few MOSFETs in the early days, well still do occasionally switching on The High-Side and the Low-Side on at the same time, haha.

[@peterstewart4559]

I really enjoyed watching your show. thanks for sharing your experience with the world I have learned a lot from you thanks man keep up the good work👍

[@mauanderuk]

Odd job hands lol I think these are your best videos many thanks.

[@Colin6712]

Love your video's, electronics fascinates me i wish i had learnt electronics when i was going round a mates many years ago he was really good he designed and built circuit boards from scratch he had every certificate going god i wish i watched more

[@scroopynooperz9051]

Richard is a Top G! How did you know i was opening up my blown amp today? 😂

[@mikebond6328]

I was working on a long winded comment about air pressure and before I could finish it you started to explain it so I said Ok, never mind then. 😂

[@peterbedford6769]

great video thanks .

[@vianacode]

Great Class!

[@RichardGriffin-r1g]

Great Lessons! Looking for schematic for PMX 602D-Usb Powered mixer purchased from Amazon ! No seller info ?

[@warwickbunn1250]

Are the various types of amplifiers used in different types of audio systems ? I.e. do top end equipment use a certain type due to the better quality output, compared to a cheap and chearful set up ? So that you could look at the circuit and know what sort of quality the product is.

[@ralphj4012]

A suggestion (and my opinion only), is to show 0V reference (or whatever you want to call it) as a single horizontal line, chassis as a single horizontal line with backwards facing lines under it and mains earth (sadly also known as ground) as single large with smaller horizontal lines. Then paranoid engineers, like me, will go to one's grave contented.

[@jasonsomerville2504]

I was going to post the same, rather than earth symbol, for completeness use the chassis ground symbol in this instance would be more accurate, but the principles discussed are spot on...thanks Richard

[@LearnElectronicsRepair]

Yeah I agree with you it wqould have been better

[@Dutch_off_grid_homesteading]

Heya, oke I believe I untherstand, well I mean the differant workings of the amplifiers classes. the working and the why to use an isolation transformer. wen I was in my teen years I got the faraic but only the trafo and the taproler for the trafo the rest I had to bild my self and it worked good between 0 volt and 220 volts te limiter you bild I have the compponents to bild that too. and I think because of lack of experience I have the feeling of I don't know. but still learning more thanks

[@Dutch-linux]

with the speaker terminals there is no zero either as the return is also a voltage that flows to the other connectors and there for it is not zero ... timestamp 11:40 by the way

[@TheElectronicDilettante]

Analog Devices(Maxim Integrated A.N.3977) has an excellent paper on the Fundamentals of Class D Amplifier operation. If anyone is having a hard time grasping the topic, it’ll help to reinforce what Richard explained.

[@Cleofizoid]

"Ground", "zero" or reference in your example is DCC or DC Common.

[@andygardiner6526]

I think that was Rich explaining his Theory of Relativity :-)

[@stevewebb5735]

Their capacitor arrangement looks a bit dodgy for voltage imbalance issues - it may explain why those two 100v caps partially failed

[@danieljohnson8437]

3 Excellent Knowledge.,

[@pault6533]

By definition, DCV is incorrect. If current is not required to have a voltage potential, why do we call it Direct Current Voltage? Seems like a good way to confuse people.

[@andymouse]

A lot is a throwback to old ways of thinking , just learn it and love it.

[@Manticore1960]

@pault6533 When writing, I tend to use Vdc & Vac. The lower case letters show where the upper case letter was derived from or referenced to. i.e. a voltage derived from a direct current or alternating current. You can't speak in upper or lower case obviously, so I would say "volts d c" or "volts a c". Saying "d c volts" or "a c volts" is just another way of saying the same thing with the words in a different order.

[@GiC7]

Nice

[@Dutch-linux]

at the speaker on the where you say 0 volt is not really 0 volts there is the return voltage too and puts a voltage on the 0 and ground is really not a good naming .. it is better to say neutral ... as it is neutral to the both of the positive and the negative voltage you measure across the speaker you got voltage of the ground would be 0 then there would be no voltage across the speaker ... when there is no power coming in like the supply is turned off or unplugged you have 0 volts .. but it be 0 volts on all wires !!!!!!

[@LearnElectronicsRepair]

I was trying to make the point that in a class A/B, G or H amplifier when there is no signal the output stage is basically idle, with a class D the PWM, and therefore the output stage is running all the time. 0V was with reference to the centre tap on the transformer. Sorry if i wasn't very clear about that.

[@jonathanrose456]

❤

[@Dutch-linux]

but when you short either positive or negative to the ref it goes bang and also when you short positive and negative it also goes bang ... as said before there is no zero volts and don't get me started on phase shift and 2 and 3 phase !!!

[@LearnElectronicsRepair]

Of course.

[@Dutch-linux]

these days most amps are class D or class H

[@andrewreed7101]

I really enjoyed your channel till you forced me to watch so many ads.

[@LearnElectronicsRepair]

I didn't force you to watch any ads 🤔

[@andrewreed7101]

@@LearnElectronicsRepair maybe it is in your settings. KZbin is showing 2 ads like every 5 minutes. It’s exhausting!

[@glennkingdon5129]

I use FireFox and they have an advertisement add-on that eliminates the ads, I watched the video and didn't have a single advertisement.