Super detailed and very educational. I was trained as an EE many years ago but have not practiced as one for over 20 years but I’m jumping back in now as a hobby and it’s great to get a refresher on basic principles like you offer here. Keep up the except work!

Great to see you Peter back in bussines.Full of energy and plenty experience its a real pleasure to follow you're work ! Bleib Gesund und Danke Dir !

Thank you TRX! This was a beautiful video, rich with helpful content and tips, not only on fixing this SMPS, but so much more, so well explained. Congratulations on a video well done!

Peter is back with a gold mine! The tech who goes inside the heart of smps circuits. Show them electrons moving around. By the way, you got one of the best handheld multimeters on your bench. At the top on the same level as the Flukes.

Brilliant diagnostic work! I have a SMPS that operates my disabled wifes reclining chair that she sits and sleeps in. The original PSU failed recently failed so I bought her a cheap Chinese replacement replacement but I would like to repair the original unit. You have given me many avenues to try and fix it. Many thanks Lynton G4XCQ

Great! Id like to see you repair Professional military hf receivers like Hagenuk, R&S, Racal etc! I'm very happy that you come back again here ! Danke! Ciao ! 73

This was a great series on smps. Thanks very much for this.

Thanks a bunch for this! Such a broad view and lots of information condensed in this video!

Hi Peter, thank you for the video; they never fail to increase my knowledge. 73's

Im so impressed by your knowledge and all nice equipment you got Peter 👍🙂

I ran a Motorola Communications Business for 26 years, and watching you work with all the high tech equipment, makes me think of the thousands of dollars I could have made if I had excess to such at the time.

Hi Peter. So glad that you are back making electronic education and repair videos. I really appreciate that you started at the mains and went through as much checking as possible without removing the board from the chassis. Also really like that you showed us the different types of switching power supplies and how they work. I know that you could have just checked some different test points and located the faulty regulator, but that would not of helped all of us that had no knowledge of how switching power supplies worked. Thank you again. John C

This series was extremely informative. Thank you.

One of the best!!!!!! Thank you Mr. TRX.

Thanks Peter, I know so much more now about SMPS inner workings. Stay safe! 73 - Dino KLØS

Finally a good working SMPS. Fine climax of a good video series, it was a pleasure. Well done, Peter. Bleib weiterhin gesund! 73 de Olaf

Really excellent! Thank you TRX Lab. 👍

Great video. You have all the fancy toys.

another great video. Going to use some of your techniques on the jetstream power supply i am working. It is looking like the problem is in the controller board. When I get some more time I will work on it. Keeping the videos coming.

Hey glad your back *:* *)*

Lots of great information. Thanks Peter.

Amazing video. Videos like these are helping me to learn how electronics work and slowly build up my knowledge. Very enjoyable 👌

Very good and very well explained sir. You went above and beyond what you needed to to explain what you were doing during the repair. Thank-you. :-))

Nice job love your explainations to detail. Seems like that power supply has been around the block a few times but still kicking. We know that camera gets in your way if you could mount it over head pointing down at what your working on I'm pretty sure it won't be in your way. Thanks for all you do to bring us some more great videos 73

Nice video peter. Really thx very much for the effort and time dedicated yo show us the troubleshooting process. See you in he next one :)

Linear power supplies are my specialty when I was a tech. I'm 72 now and just cannot see as well as when I was younger. I understand linear supplies better than switching supplies. I have found that failing diodes are the most common failure in linear supplies. Of course I only have 120 volts AC to deal with here in the US. Very seldom do you have to replace a failed capacitor. I've also seen burnt resistors in the circuits. You can make most repairs with a good multi-meter. W Rusty Lane K9POW in eastern Tennessee

Very nicely done. Really explains how this type of power supply works.

Great video. I like the way you took us through your systematic troubleshooting method. I don't know if you noticed this or not, but it seemed like the ground pin (center pin?) on the voltage regulator had what appears in the video the first time that you showed it from underneath, a cracked solder joint all the way around. If my eyes are working properly that could have very well been the cause of the regulator not passing any voltage. If you noticed it and reflowed the solder then of course the replacement was necessary. Again, great video. thanks for sharing.

"That was a sentence, 0 my gosh".. Great work with added humor. Made me laugh and learn at the same time. 73s

Fantastic video. Please keep up the circuit analysis diagnosis explanation type video with schematics. You’re a really great teacher, it’s obvious that you put a lot of effort into this. Thank you very much.

Thanks for a very informative and educational video series I really learned something.

Good Lord, whawt a nice explanation. Thanks Peter.

Awesome class, thank you.

Hi Peter, just watched and enjoyed this video again. Thanks for the warning not to use a valuable and precious scope for circuit measurements! To prevent scope damage, I use a 500VA isolation transformer, that works fine and prevent main voltage hazardous situations. Thanks a lot for all your great videos! 73’s, Nanko, PA0NVY

Well done! At times a little over-explained for my tastes, but necessary for a good teacher. I enjoy your voice and your accent. You voice reminds me of training engineers years ago from Krautkramer back when we would get training on a new instrument.

Finally I found time to watch this 🙂, totally agree with you: SMPS can seriously destroy your day if you don't treat them with respect. Love the Polo shirt buddy, it's a great colour.

I love videos like this. Would also to be great to see some video about theory/troubleshooting active PFC circuit. Many thanks and best wishes.

Nice repair. Guess it wasn't too difficult to remove the main board. The controller board might have been more difficult to diagnose due to its position. Blue Ringer kit ordered, thanks for the tip. Take care Peter.

Great explanation

Great explanation! I somethimes fix SMPS powe rsuply, but my experience on that isn't good as your. I was rarely lucky like that, there was in most of cases, Mosfet blown up, and also the IC oscillator ( or its circuit) with troubles. Somethimes there was also issues on feedback control circuits. Often, of course Capacitors... specially those ones in the secondary side that are specific for hig frequency switching, with low ESR that, if too much aged, cannot do their Job as well. I love the way as you explain all the job! it is a good way to teach, theory adding practical measuremet and how to do measurements in safe and right way. I saw also a usefull instrument to make safe the measurements with oscilloscope (Micsig DP10013), in future i will buy one same as your. You have plenty of nice instruments... that Sencore LC77 is really amazing. Thank you for all the explanations... i will follow you to learn more. I would also contact you if possible to ask you something about your R&S CMT 54 .

Man you have got some test equipment in there👍👍👍

really in deep thanks peter 👍

This channel its funny, even for those who are not either Technician or Engineers 😎

good job dear.

amazing sir , i love the way you explain

I do not know how I missed this tutorial. Out in January for me to only come across it in September. This tutorial is fucken too good, hammering the points home practically as well as theoratically. I wish you can do one on VFD's. Thank you very much.

Thanks so much for the videos. I normally watch your videos for the entertainment value mostly, however this time is different. I'm re-watching this one actually because the SMPS in my Icom IC-7800 stopped working. I know nothing about them. Icom expects you to replace the entire unit at $1550 USD and will not supply a schematic. I was very fortunate to find someone on the internet who had a copy that was drawn (reverse engineered) by some hams. I have 322V high voltage and I have an ACLV of 63volts. So here is my question, I have a scope that runs off of a battery. I normally keep it plugged in to mains power to keep the battery charged. Would it be safe to unplug the AC cord and run it off of battery power and it be safe to use to probe the power supply? Based on your explanation it would seem so but I don't want to try it and be surprised. I've only ever repaired one SMPS and that was on an IC-736 and all I did was replace all of the electrolytic capacitors. I suspect an old capacitor is the problem in the IC-7800 as well. Thanks for any advice.

I still have my old isolation transformer. I sometimes have some line noise and was wondering if the isolation transformer would remove the line noise. I think it may be coming from the refrigerator, just not sure. It could be some vortex over my QTH messing up my VHF frequencies. I've only noticed it on VHF and never HF. What you suggest? W Rusty Lane K9POW in eastern Tennessee

Thank you sir . informative video about S.M.P.S repairing.

Good series here Peter. Though not seen here but I have owned switching supplies that are non-isolated that use an inductor instead of a transformer. A voltage sniffer would come in handy or this diagnosis...

Hello Peter great job please tell me, if I use the diff head. Test probe can really don't need what's called an Auto transformer, to get the flooting point and safety working with scope??

Thanks!

Thanks for sharing

Thank you TRX!

Very nice video. Professional work. For me missing the scope signal from both mosfet gate keys bcos I wonder over this trick: How it work and what for is implemented driving upper key mosfet gate via other transformer - so my question is: 1. Both mosfet are switching in this same time or this floating source gate doing any delay between up and down key? 2. What here is domination wind - from gate side or high side of transformer? Simply culd you explain how it work an why its implemented? btw. first time I saw forward 2t with two main cappacitors in series. Even for me I can put 2 caps on 400V for less stress this units. Also less current leaks when use 50% nominal voltage of cappacitors.

Excellent video, a simple question for you. Is there a way to calculate the minimum input current required for the smps to start up properly please?

Good day Sir Thank you very much for the informative video. I always understood that using an isolation transformer between the mains and the device under test, causes its output to not be mains earth referenced anymore(floating) and thus allows you to connect earthed equipment, like an oscilloscope, to any part of the power supply without fear of damage. So when you do connect the ground crocodile clip of the standard probe, which is connected to mains earth, to any point in the circuit, that point then becomes earth referenced. I do agree that a differential probe is the safest. Pity it is so expensive.

Suppose if you found the fuse was blown, what would you do next? How would you look for the reason for the fuse to be blown?

Hi, could you tell me with my problem. I have smps 65v DC. The coil is whinning and no output. I've tried to check any capacitor but found no problem. Thx

Thanks a lot.

So super sir thank you.

What Make and Model is the ESR Meter that you're using?

Hi Peter how much do you charge to repair amps I have 2 heavy hitters

I connected my oscilloscope directly to the mains. Even though it was a battery one it made a right old mess of the innards. The thing made a noise like 1000 components crying out in pain.

Sir can pulse be sent to igbt gate by only transistor (8550 and bc 548b) in smps ( without microcontroller or pwm ic) if yes then how?

34:23 Is it possible, that T1 has an extra winding anyway?

great to see you back Peter. been following you for a few years now . could i use the same diagnostic to repair a Yaesu ft 990 internal power supply ( it started BUZZYING then just stop ) keep up the great work, say safe , all the best from the UK

how do you workout let’s say a 25k ohms in the inside an amplie when I test them it shows 18k ohms when I remove it from the ampli

Nice Multimeter it would look good on my bench ☺

No output from voltage regulator. With power off, did you check that test point for a short to ground?

I see the ring tester is no longer in production. How would I use a standard ESR meter to know if the coil is damaged if I don’t know the value the transformer should have?

the most dangerous power supply is a high voltages switch mode power supply it builds with the inverters inside the circuits boards

Thank you

hi Peter. about reactive power, in france, authorities are actually changing our old power counter by a new model witch is a communicative counter call LINKY. but the new one is in VA... so most part of the french people (99.9%) don't know what it is about. so for some of them a big suprise are waittig them on their bill. As well as the subscription is generally for 6 kw, they will have in reallity less active power available. further more this counter is equiped with a built in cut off so if you exceed the power subscription it cut the line automaticly....big brother is in our house....creepy!!!!!

Greetings Peter, what a fantastic channel. Do you run a commercial repair workshop, that will accept repairs? Or is it only repairs for KZfaq ? Please do let me know. Many thanks !

Could you do the same for my SMPS? It's from a Crate guitar amp. I fried something when a surge accured at my house. I can send you schematic if you could tell me where to probe at points to find faulty component.

do you have a diy for this ringer tester of yours?

Hi awesome. could you refer a smps book ? I would like to learn more from power supply’s . Thanks.

Nice job, you always inspiring me. But can you please post video for this ringer tester and how to make one?

Nice video Peter. I wonder why the 7812 regulator failed though.

Guten tag.Graupner ist gut mark Power Supply?

Why you connect smps and osciloscope through 2 transformers? Wouldn't just one on smps or the osciloscope isolate the ground? Aside from serious safety issues wouldn't just isolating the ground pin in the osciloscope plug do the same?

Oh, and you had it too easy with the defective linear regulator. I was hoping for an issue on the control side board - lol.

I wonder why manufacturers don't make test points to make it easier to test and repair these units.

How did you got schematic diagram Sir ? Thnks

hai sir that solder gun is it possible to tell me how i can get one for my self and what the name of it

Great work! You write "no discussion we need a certified transformer on the DUT unit. 2: You do NOT need a second transformer on your scope but it makes daily business much easier as you do not always think about safety issues while you are working" I ask you: Does connecting the oscilloscope via the isolation transformer require that the ground wire is also connected or can it be left unconnected? Tnks

Sir do you have abb powersupply cp24/20 driver ic number it is blown off pls help me to have that number it is 8 pin ic

Recomended isolation transformer ?

Nice observation @1:00:00

Thank I Ike it

I know this IC a operation amplied but what’s kind

Variacs do NOT (to my knowledge) provide isolation. The neutral goes straight through. How is yours different?

capacitors it’s smooth outs for an AC that’s converted to DC if a pure DC it’s doesn’t smooth outs what’s part it’s needed to add to causes it smooth outs examples 12volts DC connected to a 25volts capacitor the voltages stayed 12volts the same if using AC power converted to 12volts DC it’s smooth out almost 15volts but a pure DC it won’t works whats parts it needed to added to cause it’s smooth outs

Great. Can you please post your Word Doc with the different kind of converters. Where did you find the schematic? Thnx.

Wen it breaks, is it a Wreck-tefier? hahaha

26 Y ears is a long time. But made 1 or2 years before that.

It would be interesing to see Tom do the technical breakdown in German.

Great job. But we really an extra video where you will be talking about " power factor corrector " because the new generation of smps has a PFC.

Sir can u highlight me on how to connect universal power module