EEVblog

[@XOIIOXOIIO]

So cool that you could hear the switching frequency, it sounded pretty awesome.

[@MrCarlsonsLab]

Great tear down as usual! Would have been nice to see the output waveform on a scope, with a variable load, and with no load. I didn't think we built anything up here in Canada anymore, maybe there's still hope..... Not holding my breath :^l

[@FooBar89]

Point Grey cameras :P

[@mikeselectricstuff]

Big holes in PCB may be for airflow rather than isolation

[@doomprophet]

The frequency sound at the end made the whole thing worth while. Big thumbs up!

[@RobCCTV]

Superb. Even if I was not fascinated by electronics design (for my retirement hobby), I would still watch this for the many throw-away funny phrases that this man uses. I hope he is making a comfortable living out of such videos, because he deserves it.

[@DanielLopez-up6os]

Love coming back to these teardowns.

[@yngvai777]

I've worked on quite a few Absopulse power supplies. They all came from the rail industry where they were mounted inside train cars.

[@ronaldlijs]

Excellent video Dave, back to the roots. I need to get one of these myself for my products, at the moment just have a variac and that's it.. Keep it up,

[@mikeselectricstuff]

Black thing on ceramic stilts probably a NTC inrush limiter

[@uniment]

You're correct; when switching higher voltages, transition losses increase fairly quickly so lower switching frequencies are used. The more interesting noise here though is not the main switching frequency, but what is apparently an intermodulation product between the switching frequency and the output frequency. This IMD product is heard as a rising and falling frequency, and though it'd be technically incorrect, some people would call it a "beat" frequency.

[@MrDubje]

As afbor said: It's basicly a temperature sensitive switch (a pre-set bimetallic switch). These klixons can be bought in a variety of pre set temperatures. Other than NTC or PTC sensors these over-temperature switches can't be used to accurately "measure" a temperature of-course (like an analogue value). :)

[@EEVblog]

Smaller and lighter transformers than 50/60Hz ones. But 400Hz is no good for long distance transmission, so only of use in a confined system like a plane or ship.

[@BMRStudio]

38:59 - Dave goes to the space :))) Best turbine engine spin up sound ever :)

[@glenwoofit]

Big Thumbs Up! I had to fast forward and skip the specs as I couldn't wait to see inside...

[@ScramblerUSA]

Dave, it would be nice to have a follow-up video with scope-probing the output of this unit. I'm very interested to see its sinusoidal output. How it performs with and without the load, all this stuff. Thanks.

[@HeartOfGermany]

Arw, finally something new about frequency stuff. Will love it!

[@Andrew_Sparrow]

I've been looking for one of these for a long time! wasn't sure they exist as didn't know what to search for. Was basically looking for an electronic version of a variac. Now I know they exist! Would have liked more of an explanation of how they work, I pretty much know how they work but never hurts a second, third, fourth opinion and run through :)

[@rfcarlson1]

Also needed in applications where you're trying to detect very small signals that are normally in the range of the line frequency (like passive sonar signatures).

[@EEVblog]

I of course forgot to mention that a variac is the traditional way to adjust mains input voltage.

[@CH_Pechiar]

500!! and I've watched them all. Ohh my brain.. poor brain! Seriously, congrats Dave!

[@Coolkeys2009]

Very interesting, Please runs some loads, an induction motor or shaded pole fan motor and a high power halogen lamp. Can we see the output waveforms on scope loaded and unloaded?

[@sebastiang2296]

The sound it made (at the end of the video) was the best part.

[@oliglaser]

Great video as always Dave, thanks. Just to point out a small mistake, @35:57 you refer to the PIC16F's as being "variations of 16-bit PIC chips". I know you now they are 8-bit uCs, so I'm guessing you meant to say "variations of 16F PIC chips" here. P.S - Congrats on reaching 500 - here's to the next 500 videos!

[@AbdullahKahramanPhD]

Great teardown Dave! You have mentioned diode matching and paralleling. Could you make a video on it with maybe some demonstration?

[@wemme]

We had one of these they are bloody handy for testing usa motors and magnetics in nz/au. They heat up at the low freq due to lower inductance than 50hz magnetics

[@cognetic]

"What a dogs breakfast". Truly love Dave's witty descriptions.

[@squawkBirdies]

That switching frequency sweep sounded so trippy, man.

[@rikvdmark]

Psychedelic frequency noises. That sounded really cool :D

[@nodariel]

Very interesting. Thanks Dave!

[@ceecrb1]

9:02 The amazing disappearing hand! A teardown and magic in the same video? Bonus :)

[@pjlegault6153]

Inductors, like transformers will have issues with a higher frequency. The grunty work of filtering is left to capacitors in most power supplies and adaptors, and capacitors filter better with higher frequency input. That is a big part of why a full bridge rectifier will filter better than a half wave. You include positive and negative alternations into your DC conversion and double the frequency of your AC in your DC Input. A 60 Hz AC will become 120Hz DC pulses which filter much better.

[@STBYRUD]

Hmm, thanks for the confirmation, I had similar thoughts - I doubt that a bog standard AC to USB power supply would have any PFC in it, so they should definitely be okay then - cheers!

[@00101110o]

Listening to that frequency switching reminded me of older game audio. Something akin to a spaceship readying itself for launch (with the fan ramping up in speed).

[@Mr_Wh1]

Nice informative video as always. Thanks Dave!

[@aerofart]

Nice one, Dave.

[@38911bytefree]

Dave, you can do in a totally lineal fashion. not the best but ouput wave is clean, without any THD, and its even simpler to understand. Just put an audio power amp chip like the LM3886 or the want you have, an output tranformer to gain voltage (i.e. loss current) some feedback at the output and you are done. In that way you only need a decent DAC and a sine wave table in your uC. if a good power uC you can still generate THD that is useful, because real mains is not sooo clean.

[@TheOriginalEviltech]

It sounds like it's going to fly off to space :D Love the overpopulated boards! Feels like real quality when you pick up something made so good. I guess the voltage control is on the input board, otherwise i don't see why they'd do so much control on it.

[@DaedalusYoung]

In The Netherlands, mains wiring has Ground, Null and Phase wires. So PH probably just means phase. If you check Wikipedia "Electrical wiring" page, they call the wires phase, neutral and ground as well.

[@RandyLott]

It must use a PLL with a multiplier/divider in the loop, or maybe a DDS chip? Obviously, I'm still watching :) Can't wait for the teardown, haha.

[@CH_Pechiar]

yes, that would be nice to see. Varying the load too.

[@chuckvanderbildt]

I now read all datasheets in your voice, dave. That includes the automatic pitch increase when you hit the odd marketing bs.

[@eggraf]

YAY Representing my hometown. Go Ottawa Canada :)

[@ChipGuy]

Love teardown tuesday. Even if an item would be boring as ratshit still big thumbs up for the effort you put into these videos. Btw congrats to your 500th video (German counter).

[@gglovato]

Dave, what about checking the output sinewave in one of the scopes?, maybe at the low voltage range or using the scopemeter

[@k250014783]

Wonder if they made it go up to exactly 440Hz to get a clean A

[@berni8k]

Well if its a switchmode charger it wont matter because its just rectifying mains in to DC, but might cause problems when there is a active PFC like here. But the old heavy 50Hz transformer wallwarts might not like 400Hz because the iron core in it is not designed to be used that high and may start to heat up a lot due to eddy currents just like inductive heaters work.

[@ValdemarCamilo]

"that's probably the last voltage I set it at". Is there something you're not telling us dave? :-P took a peak before taking it apart? excellent video as usual.

[@keithminchin1817]

Would’ve been interesting to see the frequency and resolution of the SPWM signal off the PIC.

[@MMegaHz]

That thing makes the coolest sounds

[@philpem]

I'll wager they're probably using high-frequency PWM to avoid running the FETs in linear mode (and thus keep the FET temperature down). If that's the case, the chokes will be acting as lowpass filters to keep harmonics off the AC output line.

[@uyjulian]

happy 500 videos

[@EletronManiacos]

Tanks for the answer Dave =P (Live Stream Question)

[@EEVblog]

It is connected to the case, just rather poorly.

[@EEVblog]

Yep, you certainly could.

[@malcolmtill]

Hi In the UK we refer to phase and neutral hence PH and N Kind regards

[@mattmanslim]

Hi Dave, given the variable range in voltage and frequency, does that mean you could potentially run aircraft equipment from that unit? Apologies if it's mentioned later on in the video.

[@icesoft1]

Don't suppose you'd be doing a review with output characteristics as well would ya? Kinda curious how clean the output waveform looks... You might check out Tesla500's review of a APC SmartUPS, which also has PWM Sinewave output.

[@philpem]

32:00 -- Looks like it could be a UC3844 to me. AC/DC power supply controller -- would link to the datasheet but KZbin won't let me. It's on TI's website anyway...

[@electronixTech]

Hey nice, I live here in Ottawa and know about Absopulse.

[@Lodorenos]

New video, awesome!

[@STBYRUD]

Thanks Dave! I have a somewhat related question - I work on airplanes, they have single phase 110V 400Hz sockets scattered throughout the cabin and the cockpit. People use those to charge their phones and laptops - obviously way out of spec for the regular power supply. What happens to such a power supply if it is fed with 400Hz AC instead of the usual 50 or 60 Hz?

[@275drago]

Hi dave i am watching your videos for about 2 months i am enjoing every single one of them :) i watched a lot of old ones too. And i would like to see you make your own audio power amp like you did with a uCurent and others.

[@ElectronicTonic156]

Sounds like Johnny-5 making love to the Electric Dreams computer.

[@NerdNordic]

Yup. Especially at the lower frequencies. :)

[@Ghlargh]

That would be UC3844, not 3644 It's an SMPS Controller.

[@kfishy]

39:00 sounds like old 8-bit video game sounds, and then it sounds like a jet engine as the frequency goes up.

[@MrClaudiodonate]

It's so easy for you to unscrew those screws that looks like you opened it before the recording.

[@vacuumboy6.0]

CLEAR!!!!!!!!!!

[@javedkhan0258]

high frequency doesn't mean smaller motors. Can you explain how? Adjustable speed drive or variable speed drive are used to control the speed of machinery. n=120*f/p, where n is synchronous speed in RPM, f is frequency and p is number of poles of AC or induction motors.

[@1337NoMad1337]

As for mains earth: The spec sheet says it's got a floating output. So they probably didn't hook the mains' earth up to the case to keep it floating... Which for me doesn't make sense - shouldn't the mains' earth be connected to the case as a safety measure rather than the output?

[@chris746568462]

What is the price of this unit? I don't see prices on their website. They do a 1kW and 2kW version also!

[@youbecha64]

I am not an engineer, but I am sure a standard 'wall wart' power adapter, or cellphone charger designed to run at 50-60 hz would have filtering issues or other issues when plugged into an aircraft 115v 400hz socket. Could you spend a couple of minutes and test what happens in that situation? (now that you have a device that can generate that kind of power)

[@GerardHook]

Sounded like the audible switching was at a harmonic of the set freq.

[@dasten123]

39:00 nice sound effects :D

[@magoostus]

Ive got an audio amplifier (Yamaha T5N) Thats been kinda fun use to power 120v equipment from. just hook a 60hz sine generator to it :P

[@RealZomBiE8192]

I'd like to have one to adjust my tabletop fan speed. :D

[@PhattyMo]

32:05, Might it be a UC3844N (not 3644)?? UC3844N is current mode controller. (pretty common in smaller SMPS's.)

[@AmirHakimiRezaei]

Hi fives to everyone from here in Canada

[@toast_recon]

With how much manufacturing costs were disregarded, I can't even hazard a guess at how much something like this would cost. 10K US?

[@touchsmart732]

Just getting into electronics so this might be a nooby question but, What are the advantages of higher frequency AC and why do they use those frequencies in military?

[@Armchaircmdr]

Where can I get one? I am currently using a Behlman P1351 to test aircraft parts.It has been sent back once for repair (warranty), and it is about to go back again. It takes a good hit to the top to turn it on.

[@petersage5157]

Saw all those little film capacitors on the riser boards and thought "HAH!...or possibly hah." Looked like a place where any bean counters involved might have pinched a few pennies...but no, those all appear to be Kemet and Panasonic, and the big honkin' poly capacitors are Electronic Concepts. "Very impressive - spared no expense." I agree that the missing mains earth lead was a major oversight. If that were a piece of consumer gear and not pro-jobber test equipment, I can't see how that would pass certification in the US.

[@Fan119]

Maybe those Canadians had a kettle bit too much maple syrup while designing it.

[@TheManLab7]

What's the difference between "voltage" and "working voltage"???

[@defaultuser000]

That's a UC3844 chip...It's a fixed-freq current-mode PWM controller.

[@MrMac5150]

Very Good

[@david486038]

New T-shirt "Screwdriver Time"

[@aptsys]

PH just means Phase. It's the correct terminology for any line conductor not at PE potential. Hot/Live etc are technically not the correct terms.

[@TheManLab7]

39:00 sounds so cool.

[@billa8671]

lol i know right? sounds like the mothership landing

[@laharl2k]

39:00 it's gonna blow!!! lol awesome sound effects :P

[@CH_Pechiar]

At first it reminded me the subway (metro, subte, whatever you want to call the train that goes underground) when it starts moving.

[@misisisososo]

This gunk which components are stuck together with can be any material? I mean can I use basic silicon pistol to do the job ? Thanks

[@UnrealVideoDuke]

no review for the extech mini microscope?

[@Pow3llMorgan]

I had that exact same association :P

[@bnber18]

Hi Dave sorry for the nooby question but what is a Choke I dont know all the english words for the parts. Greetings from Austria

[@MrDubje]

That's what I was thinking too! It's a Klixon.

[@malgailany]

500 VA does not equal 500 W. this depends on load power factor.

[@R4MP4G3RXD]

lol that switching sound is like an outer space car that is speeding up to 3000 km/h xD

[@Lukas.H9]

istn't the first transformer only for the PFC?

[@MrSoundshark]

Pull the pics and have a look on you pic kit at the code im sure it would reveal some interesting stuff