12V 1A wifi router adapter test and analysis

Testing two donated 12V 1A switching power supplies for a wifi router, what's inside, how do they work. Examining the quality and safety, thermal imaging, output voltage ripple, waveforms, reverse engineered schematic.

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[samuelfielder]

So, actually pretty safe, but you didn't put your usual stamp on it at the end.

[d.k.]

Danke!
Thanks!

Very extensively explained.
All the details and markings.
Nice waveform showing.

How hard the maschine has to press the transformer during assembly to break the massive plastic OMG o.Õ
Nevertheless it's a working device :p

Extremely funny for me:
Dodgy traveladapter
dodged the contacts XD

[antibrevity]

It's actually pretty good considering the 1A rating; one of the best you've taken apart. Chinese transformers are tricky as you can't tell how their built with destroying them, but this one is very good and I hope that properly insulated secondaries become the norm from these manufacturers. Insulated secondaries and full-coverage tape are not things we often see on this channel.

I don't trust any AC-powered product from China unless I've bought 2 and taken one apart to see how it's built. That's wasteful, though, so I mostly just avoid things from the East Asian marketplaces if they plug into the wall :(. Battery-powered products are usually safe, even if they're cheaply built.

[andrewd]

I was expecting it to be superdodgy but it turned out to be fit for purpose.

[Alexelectricalengineering]

Actually a nice PSU, and as always awesome video 👍👍👍👍

[orpedsesama]

Two new knowledge for me, sensing auxilliary winding onky, instwad of output. And auxilliary winding doubles as imterference shield,
Thankyou master

[TheSpotify]

Not terrible considering the reasonably good quality transformer and the large separation between primary and secondary on the board. Most cheap Chinese chargers can barely have 1mm of clearance on the PCB and even less in the transformer!
Also suitably impressed that you can get 1.3A out of a charger rated for 1A, nice.

[Duracellmumus]

The THT capacitor is acting like a heatsink for SMT diode. Looks like a good design point for an always on equipment.

[anonymoususer]

Inspiring cat, Schroedinger would be jealous :-)
/chriV

[johnschneede]

Nice Video as always, I love your schematics and analysis ❤

Regarding the power supply, I have mixed feelings:

- Isolation distances and parts seems decend
- For a router supply it has nice filtering with the inductors between the caps, comparing to other analysis you made, most cheap usb-supplys had no filtering coils etc.
- From my experience, routers are not pulling the full 1A especially the low end ones (I would guess normally 5-6W) so the sizing seems adequate
- Thermal Design not so good, considering most router supplys are stuffed in some narrow places where airflow is poor

But in the End what most matters to me is the broken transformer. How can this pass the QC?

Maybe this time the fault was "not so bad" but, you never know wether the fault produced in factory is safety critical or not 🤷🏼‍♂️

Its like chinese roulette with product safety and regulatory compliance of the appliances 😂

[marcelfilms]

Those travel adaptors work great when your water cooker starts tripping rcds as it removes ground

[zeendaniels]

Can we get a series featuring "actually good/safe-ish" USB chargers? To be sure which units to buy 😁

[MlokKarel]

Your cat has similar attitude as my pugs. They don't watch their mouths at all as well... 😂 👍

[objection_your_honor]

I think they're pushing it at 1 Amp.
Have you done a video where you explain the differences between transformers?
Why is there a gap and how many topologies are there?

[pascalleben]

What I've seen on all things I bought so far and disabled (over 50 psu's now) whenever there's a Chinese factory name printed on it (on the product) it's actually good and safe.

[jcxtra]

Ooo. Spark gaps between the primary and secondary side. No CY1 cap but I wasn't expecting spark gaps for high voltage static return :>

[Azaakiel]

Look at the battery gauge of the fnirsi oscilloscope 9:45

[tootsscaf]

I would like to see how these adaptors behave in radiofrequent pollution rfi. Maybe using a spectrum analyser, sdr receiver or shortwave receiver. A lot of radioamateurs have problems nowadays with these cheap sps. Some even sell their equipment not able to hear weak signal stations in urban environment.

[tajtrlik]

Opäť ti chcem poďakovať (ako je už u mňa zvykom 😀) za toto pekné a poučné videjko, musím uznať že tento zdroj je na čínske pomery dosť slušný.

[vasilkrastev]

Please explain your welding inverter again. I started making it but I'm not sure if i will succeed