He didn't even open up the transformer, also I wouldn't call it good for running in DCM

Refreshing indeed! Inexpensive, but not cheap. It even has a low value resistor in series with the auxiliary rectification diode to protect the bootstrap capacitors in the auxiliary supply. Usually, that's not there and it grossly exceeds the ripple current ratings at start-up, and the thing ends up in a landfill in six months after the little cap dries out or bulges. I did the same thing in an SMPS I made for myself, but I think that's the first time I've seen a commercial supply in a tear down with it. It's probably a common feature in reputable supplies, but most of these things are built down to cost oblivion.

Hopefully he have only mild symptoms.

You can't charge 2 AAs and 2 AAAs, it uses the same current for all. It also terminates the charging for all batteries at the same moment. The AAs would not fully charge and the AAAs would overcharge.

@@DiodeGoneWild Yes, it senses the voltage of all batteries in series but I am not sure if you can overcharge a NiMH/NiCd cell, as they dissipate remaining energy as heat, so the AAAs would just keep toasting for a while while the AAs get (almost) topped up. So does not give great results but they are useful sometimes. Also, you would use the charging current optimised for AAAs so that they don’t experience overcurrent. Yes, it is a bad idea to combine cell types but if you know the inner workings of your charger, you can use this “option” in very specific circumstances, understanding what it actually does... But at that point such person would be probably skilled enough to modify their charger to accept mixed battery types at AAA current.

You can't overcharge NiMH/NiCd at a low charging current (0.1C, maybe 0.2C), but overcharging them at a higher current would damage them. 350mA for a typical AAA (about 900mAh) is almost a 0.4C charge rate.

@@DiodeGoneWild You are right, I forgot about that...

Yes, me too! I was worried about its transformer being unraveled. Nicely built PSU. It's not often you see that on cheap consumer electronics.

I can definitely recommend Haseeb Electronics for some great explanations on power supplies, as well as many other electronics too.

Měl to ve videu zapojené přes variak a pak přes izolační trafo :)

a remark - 2 things i would find interesting in charger review: - can you test the fusible resistors in terms of fuse functionality - what current actually triggers them. and line current would be interesting to see how badly they are actually filtered

He has covered its function in some other videos on SMPS designs. See: kzfaq.info/get/bejne/mb9-ZpyYm9fXXYU.html

@@mysock351C kzfaq.info/get/bejne/oKmlfLaDlsjWc40.html Is this and that are same

The optocoupler works in its linear region. The transistor acts as a "variable resistance", or more accurately, it can only pass a current proportional to the IR LED current. Optocouplers have a certain transfer ratio. If its 1 and the led gets lets say 5mA, the transistor will only be able to pass currents up to 5mA.

Probably Nice.

This would be a nice video in Diodes style, but basically without isolation the scope internal 0V gets connected to ground and that can be live causing a short and your hard earned money goes down the drain.

Here's a much better description of what is happening with your scope and mains supply kzfaq.info/get/bejne/rsd1f9Ry1JrPm4U.html Dave Jones puts this much better than I do !

@@andymouse Thank you. Yes this EEVblog video is in my oscilloscope playlist. Using an isolated transformers turns that mains earth reference power supply into a isolated power supply. But i think he can disonnect the oscilloscope mains earth from IEC main connector instead of using an isolated transformer.

@@baghdadiabdellatif1581 Yes you can do that, I have worked in labs that do but it is generally frowned upon, I think its ok if its your scope and you understand and also that the plug is marked up clearly to indicate that there is no earth just in case someone else uses it !

@@andymouse Thank you. I think in this case is better to probing a primary smps with disconnected power strip mains earth for the oscilloscope instead of an oscilloscope with disoldred mains earth.

Trochę drogi, w tme śpiewają sobie za niego 200 zł ;/ Trafo o 10x mniejszej mocy kosztuje 70 zł, więc jeśli nie potrzeba 200 VA to chyba taniej sczepić dupami dwa małe trafo z demontażu

Ah, was it? I didn't notice that. That explains the well-made PSU.