Julian's Postbag: #68 - Why do I buy all this eBay stuff?

[@jankokert653]

Destroying the watch at 9:20 was not cool :-/ I feel a bit sad now. Something is wrong in this world - For such a tiny and complicated thing only 99 cent delivered - that is just crazy...

[@JoePCP]

With a very small amount of research you could have taken the watch apart without destroying it. As Jan said not at all cool, almost childish from such an intelligent man.

[@BlisAx]

The resistor in the LED light is actually 39 ohms. The first 2 digits are a value the third is a multiplier. A 390 ohm would be marked 391, 39 and 1 zero.

[@Milamberinx]

Glad I'm not the only one who spotted that.

[@haxxx0rz]

23:40 Same goes for the smd resistors on the super cap bank. Those shunt resistors are actually 10 ohms each (5 ohms with 2 in parallel). Those are probably for current sensing.

[@l0ckd0wn360]

OFCOURSE its going to be lower. the cable resistance is higher and you do have load on the cable to run the display and micro !!!

[@R4MP4G3RXD]

Under open circuit conditions it's impossible for a voltage drop to occur...

[@iPelaaja1]

Uhmm.. The current drawn by the display is absolutely tiny.. And so is the difference in resistances between the long and short wire. It has nothing to do with the voltage drop. As he said, its the accuracy that causes the measurements to differ..

[@Totsudon]

If that was the case shouldn't they account for it on the IC and calibrate it on the longer cable one?

[@JulianIlett]

Let's say the display draws 50mA. The volt drop on that extra length of cable was 100mV. That means the long cable has an extra 2 ohms of resistance. Is that likely?

[@emilcarr7190]

Why dont you measure it? Maybe they ae just using really thin wire :P

[@dexasdexas3784]

If you have Cap's connected in series, you increase the voltage, but capacitance goes down. It says its 120F, so if you have 6 capacirots in series, voltage will be 16.2V, but capacitance will be 120/6 = 20 Farads

[@mnelson10000]

...And that, kids, is why you don't drink and eBay!

[@elfujo6595]

Spot on. Got that in before i could say it.

[@Friendroid]

+El Fujo that's what she said!

[@jagardina]

Could have been worse... www.theonion.com/article/man-with-complete-mamas-family-video-library-never-1592

[@elfujo6595]

As somebody with countless packages on their way as we speak, I better remove myself from this conversation. (Looking at my orders, why I have 3 different boxes of 300 pieces of M3 nylon stand offs on order, no idea, but I suppose at least two of them are different colours)

[@ChaosGames101]

+jagardina You do realise the onion is a satirical site?

[@NathonDalton]

I noticed the values for SMD resistors are being incorrectly stated on this and another video (unless I'm missing something). The resistors with "100" on them are not 100Ω. The first two digits "10" indicate the initial value. The third digit "0" indicate the decimal shift. So, 10Ω with no decimal shift is 10Ω, which can be confirmed on any number of online SMD resistor code calculators. Therefore two 10Ω resistors in parallel (10*10/10+10) is 5Ω, not 50Ω.

[@TheUbuntuGuy]

On the USB hub, there is no diode between the DC jack and the PC USB input. That can damage a PC if you plug it in since it will backfeed 5V into the motherboard.

[@JulianIlett]

Yeah, that is nasty!

[@bigsmile542]

many thanks for the this info. I was just about to do this as I got one myself.

[@TheChipmunk2008]

That seems to be quite standard. Never had a PC that had an issue with it. Big Clive reviewed/destroyed one that broke macs though...

[@TheRealSasquatch]

The c73x looks like a 2.7v voltage detector - could be the same as the T53 from microchip

[@pcuser80]

Ebay is a addiction. Once started buying goodies you can never stop. Everyday looking in the mailbox is guilty pleasure......

[@PunakiviAddikti]

The motor works by alternating the polarity of the voltage going to the coil. The rotor is a magnet with a gear on it. When the polarity changes, it re-orients. The pulses change polarity every second (because it's a clock).

[@BertGrink]

I think they are just square-wave pulses to drive the escapement of the mechanical part of the watch. No polarity changes needed.

[@Bushougoma]

20:17 Wow the USB ports don't have the mechanical support clips soldered. So mechanical stress gets put on the 4 soldered pins each time you remove and install a device. Wonder how long it will last before a joint cracks? The solder looks so cruddy I almost want to say it was hand soldered but since there is solder on the unpopulated cap pads I guess it was reflow soldered. All that aside after properly soldering the USB ports not a bad USB power strip.

[@krisztianszirtes5414]

20:13 Those are resistors. Note how those black carbon tracks connect the leds straight up to 5 volts.

[@hyperion8008]

A watch, assembled by someone earning a pittence then shipped half way round the world and chucked in the bin...sad really.

[@thehappylittlefoxakabenji8154]

still got paid for it though

[@thewolfin]

The ethical/economic/environmental impacts of China's activities are not the focus of this channel... At least not directly

[@poopandfartjokes]

I look at it as job security

[@purge98]

It was crap and the assembler should be sacked.

[@RandomHacks]

At 20:09 I'm pretty sure those are printed carbon resistors for the LEDs.

[@DejcoDoesStuff]

Or sun reflection flashes from solar panels erased his memory.

[@Stjaernljus]

looks like things i would buy on ebay while in an intoxicated state

[@jammi__]

Probably not as much the accuracy of the circuit as much as the higher resistance of the longer wire.

[@iPelaaja1]

Such a tiny current would have no effect at all. Its all due tor poor accuracy with the cheap chips. That much of wire lenght would have no effect.

[@gordonlawrence3537]

Even with the really cheap and nasty USB cables you are only going to drop about 0.01V over that length with only 20mA flowing.

[@JunkTardis]

You also have to factor in that there IS a circuit, since the display itself draws a small fraction of power from the source too

[@gordonlawrence3537]

That is what I factored in with the 20mA.

[@binaryglitch64]

About volt/current meter cables; the monitor is a load... so there will be resistance... but one does seem broken.

[@piotrchec8156]

19:50 "weird tracks" is actually common technique from 80's to put additional jumpers or resistors on single side boards. It's just carbon track on epoxy resin. No cooper, no "black coating". Here it's serial resistors to LEDs.

[@BenRazvan]

You see a voltage difference because the measuring device is at the end of different length of cable, there is a small resistance on every cable but the bigger longer the distance the bigger the resistance ant thus the smaller voltage. OhMG

[@mayankb]

the C93X on the Supercap bank seems to be XC61CC2701MR Torex voltage detector for 2.7V.. you were right about that!

[@JulianIlett]

Well found, many thanks for that :)

[@theoisle]

Maybe you should call this "search and destroy".

[@ArlenMoulton2]

the screen and micro have enough of a load to make that small difference in the voltage on a longer cable. Thin cores and bad solder joints can do this, i have seen it many times.

[@ArlenMoulton2]

so you are saying that aluminium core cable doesnt have a voltage drop over a higher distance? wow...

[@ArlenMoulton2]

John Coops I never said anything about slow learner and it is very likely that these are aluminium core cables so yes, I was talking about them. I did pay attention and I am very familiar with Chinese electronics and ohm's law so don't say I am not.

[@ArlenMoulton2]

John Coops good points but they are almost certainly aluminium cored cables. If you don't believe me, look at Big Clive's videos, it is very common to see aluminium used now.

[@ArlenMoulton2]

John Coops condescending.

[@zaprodk]

Actually i think the circuit on the supercapacitor-board is not for over-voltage protection but to balance the charge. When you connect capacitors in series, any variance in values causes each one to charge at a different rate and to a different voltage. The circuit shunts a resistor in series when V-in in applied and so balances the voltage over the whole pack.

It is 10 ohm and not 100 ohm, the last digit is the number of missing tailing zeros

[@avejst]

supercapasitors; 100 is 10 ohms resistors.10, and 0 zerros efter the først ciffers: 10 ohms. mabe the sot23 is some sort of microcontroller ?

[@kardeef33317]

its reading at the meter.I have tested alot of cables ,depending on length and wire size the voltage drop can be significant.If you cut the longer cable to the length of the short one and measured at that point with a VOM you would see that the gauges are reading correctly.Heck just measure the voltage at the end of the cable with a meter, you might be surprised to notice the meter on the cable usually isn't that far off.

[@shlomsi2000]

Those strange tracks on the USB hub PCB are probably printed carbon resistors, and they are used to limit the current to the LEDs.

[@BertGrink]

You're probably right; when I saw them they seemed familiar, and your comment made it 'click'; they look just like the key contacts on a cheap calculator.

[@peterjones2411]

I think the circuitry on the back of the super caps is to prevent an uneven voltage due to capacitance variance. If one cap is smaller than the rest it will over volt. The circuitry will be to shunt over charge away and is calculated to the cap tolerance. It won't shunt much more than the cap variation.

[@poptartmcjelly7054]

The devices on that supercap board are most likely a TL431 and a NPN transistor, a MOSFET would need a gate discharge resistor and a higher voltage to run. Also you might find that the protection kicks in at 2.5V since that's the reference voltage of the TL431.

[@alancordwell9759]

"I reckon I could draw A LOT more than 500mA".... sounding worryingly like photonic induction there Julian!!!

[@pauls0416]

Well I think the "500 mA protection" that the Chinese company indicated simply meant that one of the metal traces on the board would fuse over 500 mA and the current would stop flowing...BRILLIANT !!!! :)

[@koloec94]

probably just took what standard usb is rated at for current draw

[@3butalcomp3]

I say the manufacturer should fuse that land, & make fuse accessible. The land shouldn't **burn up** as the land's orig dimensions and properties is critical for accuracy. Burn that land by mistake and jumping it will restore operation but your accuracy is probably now off a bit especially if a component's value has changed. I don't know if there's a calibration control on the pcb but if so you're lucky if you have the prior readings. -Just a suggestion-

[@-yeme-]

16:00 Ive got loads of those little lights, basic ones, touch switch ones, dimmable ones, different LED packages etc I love them every time I see a new kind I order some one thing, isnt that resistor 39 Ohms? I thought the last digit on surface mount resistors was like the last band on through-hole resistors, a power-of-ten thing, how any 0s to add. if it was 390 Ohms it would say 391

[@0410paddy]

It is a 39ohm, you are correct 😀

[@rondlh20]

39 x 10^0=39 ohm. The resistors on the super capacitor board are 10 ohms, not 100 ohms.

[@Landrew0]

I think you're wrong at 21:27. I have one of these, and it cuts out on overload. Resets itself after a few seconds when you unplug the power.

[@PhattyMo]

The longer USB cable might show a lower voltage because of the voltage drop across the longer wire. There must be some kind of small current flow,since it's powering the LED meter bits.

[@torqued666]

I bought 35 of the USB lights six weeks ago for $7. Thanks for showing me what they will look like -- if they ever arrive!

[@Th3Su8]

The closest I could find on the small SOT-23 (C73X) device is a XC61C series voltage detector from Torex Semiconductor. The other one I cannot find anything on so I presume that it is a transistor of some type like you describe. According to the data sheet I found on the voltage detector the pin out looks correct for that application.

[@RAAFtiger]

The 500mA on the USB hub packaging is the maximum output of a USB 2.0 port on a standard computer. USB 3.0 has a cap of 900mA as far as I know. The power port on the side of the hub itself allows it to become a powered USB hub meaning that current can be drawn from a place other than the port it is plugged in to.

[@bzoli5706]

For lightning or variable load you can buy 1.1 HUB much cheaper with white LEDs inside.

[@bobbybiggs4348]

the extra black traces could be printed resistors. I work with washing machines and take care of the components level PCB repairs, a lot of them (particularly Bosch) have them. they're a pain. would make sense since they seem to be running to the blue LEDs.

[@Zodliness]

Good video! A classic case of 'Chinesium Landfill' at it's very finest. LOL - It actually looks like a useful in-line meter. It's never going to be accurate, but should prove useful as a 'quick test' power assessment, if you can acquire one that functions properly. PS. At 12:20 you questioned why the battery would not power the watch, I believe the steel backplate (removed 11:10) also functioned as a 'positive earth' terminal for the battery.

[@Zapp3012]

Isn't that a 39ohm resistor? 3-9-0(no of zeros being 0).

[@JulianIlett]

Yep, you're right

[@Ohm7111]

And LEDs are not is series.

[@fpgamemearray]

they are usually running 3 LEDs in parallel, giving them 20mA each to work on. there's simply not enough voltage to drive 3 LEDs (i guess 2835 type) in series while limiting the current via resistor.

[@jamesmdeluca]

Watch runs from a mainspring partially wound by that solenoid coil via a switch when the mainspring is almost out of torque. I assume the ticking is by the conventional balance wheel/escapement system. I do not know how the xtal is used. Maybe the tick is simulated audio by a chip using the crystal.

[@Graham_Langley]

USB LEDs: Let's have another go at that resistor, shall we. 39 x 10^0 is? And the LEDs are connected in what arrangement, bearing in mind their Vf is around 3V and the USB supply is 5V? (Repost as original deleted in error)

[@JulianIlett]

Hands up! My Bad! Schoolboy errors :(

[@Graham_Langley]

+Julian Ilett Always wondered why they went with a numeric version of the colour codes instead of just printing the value.

[@woooweee]

usb socket leds + hub + powerbank makes for a decent work light because its self standing and the light is directed to the side and of course massive run time.

[@BeezyKing99]

That dual port power bank, I used to have one, one side was 1A, the other was 2A... that may also be the likely culprit behind the difference between the two ports... mine hated having both ports used at the same time so more power went to the 2A port than the 1A port.

[@wuzongye]

One mistake you made, the number on smd resistor is 390, its not 390 ohms, it is 39 ohms. The first two numbers will indicate the significant digits, and the third will be the multiplier. So a 390 ohms will be actually marked with number 391 on smd resistor, and, 392 for 3.9k ohms, like so on.

[@cwgreenley]

Also those LEDs can't possibly be in series, 5 volts wouldn't be enough voltage to overcome the required voltage drop

[@jeffflowers5489]

I have some of those USB lamps. They're nice but the resistors are a little undervalued and get hot. Also, the end opposite the contacts has a solid metal strip which will probably short out your USB port is you plug it in backwards.

[@Aslyuriel]

As a jeweller and watch repairer, I can inform you that to open the circular back watches properly you require a jig, Some twist off, others pop off. Generally the circular ones twist off and the square/rectangular ones pop off.

[@Q_Branch]

It may be that the longer wired unit just has more of a voltage drop, it is measuring the voltage at the end of the extension, not the beginning after all...

[@gazzaka]

actually there is a load , if only the measuring device, so cable length might affect it

[@JerryEricsson]

I purchased one of these after watching this video. You see it looked like the real deal for charging our devices in our Motor Home, where we spend our winters, and as much of our summers as we can. It did the job rather well to be honest, I really love it. I hooked it to a massive 12 -> 5 volt step down transformer, and it charges everything I plug into her. This makes two charging stations no in our rig, this one works when we are on the road without shore power, and I have another multi 2 amp charger that handles most of our stuff when we are tethered to the 120 volt world.

[@mplabs23]

I actually bought one of these magnetic levitation things in Chicago at the Adler-Planetarium, 15 years ago. So much for new, by the way. Mine also has some LED lights that turn on and off while it spins and does look kinda cool. Thanks for the happy memories :)

[@chrismitchell6478]

go to the store and purchase a half a dozen extension cords plug them all in end to end and check the voltage at the outlet and at the end of the chain, the voltage will be lower on the end of the long cable. There's resistance in the cable that is what is causing the drop. it's not a lot but it's there.

[@jameslamb4573]

I'm confused, I thought 390 on an SMD resistor meant 39 Ohms, similarly 100 meant 10 Ohms, mmmm?

[@jakp8777]

Those stickers on the board are jumpers. Under the ends there is no solder mask on the pcb and the black part is conductive.

[@MegaDjsmithy]

there is a .1 voltage drop in the cable due to the length, and there is a current draw front the lights on the voltmeter!

[@colepdx187]

I think the watch might be broken. I've noticed with my power-banks that any port can be used for supply or charging. Connecting two together just equalizes the charge between the two. If I leave it plugged into my car charger, it tries to power my cars electrical system when I shut the car off.

[@_Piers_]

I think Julian may have been trying Clive's booze recipes...

[@Saxie81]

Lol. I love Clive

[@TheHirade]

yesh but Clive is knowing what he's doing...

[@demonkey123]

TheHirade your rude!

[@mshahabas]

Julian My one cell aluminum power bank, exact one that u have here charges/overcharges to 4.3V and some batteries are not happy with that fact and get extremely hot!

[@_Piers_]

I'd pop it in the bin and get a different one, lithium batteries shouldn't get hot when charging.

[@jayls5]

On your USB light, those LED's are actually wired in parallel - not series like you said. If the only thing on the board is a resistor and your source voltage is ~5v from the USB, then the LED's wouldn't even be able to turn on if wired in series. They would need to have an impossibly low forward voltage of 1.66v, so we can conclude they are actually wired in a parallel arrangement.

[@adabraakman6343]

The black streaks are probably carbon printed resistors which is essentially similar to pencil lead in which it conducts electricity but still offers resistance

[@StonyRC]

Julian, we are all delighted that you buy the stuff that you do because it makes for an amazing and informative channel ... but sometimes you really do buy some crappy stuff. Please never stop!

[@vgamesx1]

I'm not sure but it looked like your little power bank was drawing current but it was so low that the meter couldn't count it, because there was a voltage drop when you plugged it in, if it wasn't charging then surely it wouldn't have dropped right?

[@waterskierjohn]

the long one would drop voltage over the lengh of the cable as the display does draw some current which is not shown on the display

[@Mr.Unacceptable]

I've had to put up the window mount air conditioning every summer for the month it's way to hot for me. This year it's still in storage. First week in July it usually goes up but it rained for the entire month with the exception of 4 days. Hasn't gotten above 27C yet. I'm in B.C. Canada.

[@jamesmorgan7699]

The black track is a carbon printed resistor on the hub

[@jammi__]

I got a a few of those "7 port" USB hubs in the past. The configuration is supposedly two 4-port hubs connected "in series", the last port of the first hub connects to the other hub, but only the three ports next to the USB lead works for data, so it's basically worse than a cheap 4-port one. The switches also just cut the 5V, leaving the data connected, which messes most devices up requiring an unplug and replug to get them going again. IMHO they shouldn't have bothered with the hub stuff, because it's not working properly like one.

[@blaser80]

Those Volt/Amp meter cables look great, I'll have to pick a few up. Cheers

[@frac]

I'm guessing those are carbon film "jumper" stickers. Neat concept. Cheaper than wire jumpers I suppose. They won't carry much current, so they'd be doubling as fuses... intentionally or not.

[@garagatza]

You had higher voltage on the short USB volt-amper-meter USB cable because of length of cable which adds resistance.

[@uN1Qu3DZ]

The resistor on the LED lights was 39 ohm not 390. The last digit on SMD resistors is the amount of zeros you put in after the first two digits.

[@neilbarnett3046]

If they are both 5.1V, then no current should flow, no PD. The point about charging a phone is that you "push" from 5V to the 3.6V Lithium cell in the phone. Odds are that the ports on your 2-port charger are connected together.

[@dawn1berlitz]

Julian that 0ohm resistor is may be what is acting as a fuse since some manufactures use a 0ohm resistor as a fuse with Dell being one of them on some motherboards

[@eirikmurito]

its incredibly addictive. every day i get at least one package. 3 today. i especially like when they send it in those little paper bubble wrap packages, i think thats what causin my addiction..

[@OliNorwell]

same for me this summer from aliexpress - 74 parcels in just over a month! the postman hates me

[@lizardofoz5329]

My cardboard sign will say "Arduinoholic Need money for ebay

[@3zuli]

The weird black tracks on that USB hub PCB run from the power switch towards the LED. I can't see any resistors on the video, so maybe these tracks are made out of carbon and form resistors for the LEDs?

[@moth.monster]

I have one of those USB hubs myself, it's quite nice. Especially with an external power supply, it works pretty well.

[@mikegravgaard340]

There is a load on both. How do you think the display is powered? Magic? Also longer cable will have high resistance due to length of the cable length.

[@thepituk]

@ 17:15 I bought one of them hubs and it stopped working after 3 days they are rubbish if you are going to us it on a computer for webcams.

[@jeffflowers5489]

on the first cables you compared, the readout difference may be due to the longer cable having more resistance.

[@sebastianjones7589]

no

[@AdammP]

for anybody interested in charging current of mobile phones or android devices there's a nifty app in the store called ampere, i use it quite often to determine the quality of aftermarket cables. using a z3 compact the standard charger gives out a peak of around 1300ma a two meter length one i purchased of ebay only supplied around 300ma. which isn't surprising given the length but interesting non the less

[@huwbishop6995]

I am very interested to see you play with the supercaps. I have 6 of the maxwell 350f caps starting my car at the moment. They were the best part of £60 for a total of 50 odd farads useable capacitance. These may have some merit.

[@Shadow-rl8cu]

4:50 "There is no load so there is no voltage drop" SO... the screen lights by itself and microprocessor works on black energy from space... Nice products you have there

[@johnb8753]

I have been looking at those banks of 6 supercaps for a while now, wondering if they would make a good replacement for a burglar alarm battery. I was also wondering if there would be enough energy to help start a car that has a poorly charged battery. Someone on KZbin has done this but his supercaps were somewhat bigger than the ones in Julian's bank. I just thought these suggestions would be good ideas to include in the upcoming video dedicated to the supercap bank.

[@SomeMorganSomewhere]

Looks like the USB hub is using printed carbon resistors for the LEDs not sure what the two at the end are though.

[@Cisco8484]

That supercapacitor module will look like a dead short when it's empty. You might want to put a low value high wattage resistor in series initially. Too bad they aren't Maxwell brand.

[@JulianIlett]

That's ok if the charge source is constant current

[@tmdcbass]

Well Elna's not too bad either, is it? (provided of course they're real, haha)

[@nissimzur1]

capacitors in parallel with have same voltage. So only 2.7V can be pulled out of the super capacitors. Not 12V.

[@linksmith1057]

Best method for getting the backs of those cheap watches are the double sided utility blades, and the battery will be an SR626 or a 377.

[@kevinbyrne4538]

25:12 -- *C73X* = Torex low voltage detector of the XC61C series in an SOT-23 package Here's the data sheet -- www.semiconductorstore.com/pages/asp/DownloadDirect.asp?sid=1496097767367 The markings are explained on page 4 -- C = 2 (first digit of detected voltage) 7 = 0.7 (second digit of detected voltage) so C7 = 2.7 volts 3 = no delay time X = production lot

[@Edu_RJR]

are those on track resistors for the leds? 20:00

[@FaradayVest]

You lose voltage on long 5V lines... My 5m long cable drop from 5V to 4V ;(

[@mikapirinen2403]

(20:00)They skipped usb protection, because usb output port need be protection .

[@sim6680]

actually the leds on the usb lights are in parallel and the resistor is 39 ohms ;)

[@Raducki]

i bought the same 19:06 with less ports and i was disappointed to discover it does not come with an external power for the socket. even the seller could not tell me what socket i could buy and use ! did you found out ?

[@Raducki]

any toughts ?

[@TheRAZZITEAK]

No current? No load? Surely the LED display doesn't run on air ;)

[@iPelaaja1]

The display would take a tiny amount of current, no way that affects the voltage at all.

[@robertcartier5088]

Correct. The tiny draw would not affect much, but that was not the point. The narrator dismissed the length of the cables as being the source of the voltage discrepancy by saying there was no load. Well, obviously there IS a load, and the difference in length of the cable does indeed factor into the reading because of its resistance. I don't claim to have calculated if this is enough to drop 0.1 volts in a 1 meter cable, but I wouldn't be surprised if it was. Cheers!

[@GadgetBoy]

The protection circuit is under one of the blobs.

[@Psychlist1972]

What the hell did I just watch? Did I really just see someone buy a crapload of cheap junk, break it, and then throw it away? :)

[@Psychlist1972]

Ok. I kept watching. It got more interesting. :)

[@BoxOfSnoo]

Well, basically yes :D Better that Julian does it than you and I. Sometimes he finds cheap junk that is really worthwhile though. Or at least educational.

[@uN1Qu3DZ]

On the USB 2.0 hub: They put extra tracks in for a capacitor they didn't populate. That's quite some design! :D

[@renxula]

Those aren't 100-ohm resistors, rather 10 ohms

[@uN1Qu3DZ]

Same for the resistors on the cap bank: 10 ohm each, not 100.

[@ElectronicCreations]

It is accurate but voltage is lost because of the length of the wire and internal resistance.

[@8bpspfreak2]

Oi, I've got m charger doctor showing me 5,09V from a USB power supply. When I plug in 3 USB Extensions in it without any load and only the charger doctor connected, it shows around 5,01V. So there seems to be an effect by cable length. Or cable quality. And if I plug in a load with those 3 extensions, it some times drops to 4,3V, some times to 4,1V :DD I guess I should change the 3 USB extensions with one 230V euro extension cable and then just plug it in with either one or no USB extension c: Edit: I've got the exact same 7 port USB hub last week!!! :000 It is utter bullshit. USB 2.0 my ass, 1,2MB/s transfer rate for all 7 ports combined xD And the USB lead only let's through about 300-400mA, then each device gets less and less the more you plug in/turn on. BUT if you use the power plug (AND NOT insert the USB lead ANYWHERE cause i've heard it might kill your PC/port/power bank) you can get up to 800 or 900mA of power without problems! And of course the same current-limiting-per-port-due-to-shitness starts again. I would recommend to use two-sided USB lights, so the switches and the blue LEDs (which consume about 30-35mA when all are turned on) are on the "dark" side and the USB LED cards can actually shine around without having the switches and the hub's surface AND the blue-ness of the LEDs in front of them. ...bought it because absurdness and plugging in exactly these kinds of LED cards for no good reason whatsoever \o/

[@LeoTheHuman]

Well, there's load. The meter (at least the LCD) is a load! And I bet it adjusts for a current it draws itself, or it just measures the current on the other side.