eBay trash USB charger 2023 - with schematic

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  • čas přidán 21. 08. 2024
  • Much better than the last similar looking unit, and this one is easily hackable to your chosen current by swapping resistors. In this video I did a simple hack for a 24/7 trickle charge.
    This unit is worth buying just for the case alone for your own custom charger project.
    I get the feeling this is another clone of a clone - where a circuit has been modified without fully understanding the purpose of some of the components. In the case of the strange pair of differently sized parallel resistors, I think it may be based loosely on the previous unit which had a similar arrangement.
    As supplied, the unit works as a very simple charger, but the current is high enough to require that you remember to take the cells out of it after a suitable length of charging time. It's too easy to forget that cells are charging and a prolonged period of high current overcharging can be detrimental to cell lifespan.
    NiMH (Nickel Metal Hydride) and NiCd (Nickel Cadmium) cells are not like lithium cells, where there is a very decisive end of charge state (usually 4.2V). Instead the smart chargers have to detect a slight change in voltage when a cell is fully charged and bubbles start to form on its electrodes, or they may detect a rise in temperature or stationary voltage. When a NiMH or NiCd cell is fully charged it has a chemical reaction internally that converts the gas bubbles back into liquid, and during this there is heat generated and higher internal pressure.
    For fixed current charging at higher currents you do have to avoid overcharging as the chemical reaction that recombines gas to liquid is only capable of handling a low level of charge current.
    At very low trickle charge currents, the cells can be left charging continually without affecting their lifespan too much. However, the trade-off is the time taken to charge the cells. Not an issue if they're just being topped up or being kept on standby.
    The other advantage of a simple charger like this is that it will handle older cells or ones that have been accidentally over-discharged, where a smart charger will either not recognise their presence, misinterpret them as being non rechargeables and reject them, or terminate the charge far too early.
    In the case of accidental over-discharging, a seemingly dead cell can be brought back gently in this type of charger before being charged quickly in a smart charger.
    Because the charger doesn't do any tests it will also work with difficult cells like the low capacity ones used in solar lights.
    Aside from the hack/mod that I show in the video, you could also just fine tune the current by swapping the 18 ohm resistors for a higher value.
    If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- www.bigclive.co...
    This also keeps the channel independent of CZcams's algorithm quirks, allowing it to be a bit more dangerous and naughty.
    #ElectronicsCreators

Komentáře • 374

  • @stepheneyles2198
    @stepheneyles2198 Před rokem +187

    I can see Clive making a video in 5 years which shows that they've watched this and changed their design accordingly!

    • @frogz
      @frogz Před rokem +12

      @@Okurka. screws cost money, i bet they will evolve to a snap together or plastic welded case

    • @dcf476
      @dcf476 Před rokem +4

      ​@@frogz which will we get to see, the one, the only, the vice of knowledge 😁👍

    • @madworld.
      @madworld. Před rokem +1

      @@Okurka. 😆🤣🤣

    • @BrownEyePinch
      @BrownEyePinch Před rokem +1

      Not Amazon

    • @RonDogInTheHouse
      @RonDogInTheHouse Před rokem +2

      @@Okurka. They'll make 2 versions (1) for us mere mortals that will be impossible to open. (2) a Big Clive version that opens instantly upon arrival, so he can re-engineer their poor design.

  • @TopEndSpoonie
    @TopEndSpoonie Před rokem +51

    Hahaha. Take out 6 components, add 1 and make the whole thing better. Great work.

    • @Globaltalentgt
      @Globaltalentgt Před rokem +3

      ❤Top end

    • @Tim_Small
      @Tim_Small Před rokem +10

      Don't need to add the extra diode, or remove the pair of low value resistors tho' - with just the 18 ohm resistors removed, the LEDs will block the reverse current path.

  • @Ni5ei
    @Ni5ei Před rokem +142

    That beefy charge lead probably contains at least 4 strands of wire 😂

  • @EdgarsLS
    @EdgarsLS Před rokem +22

    you don't have to replace the 5.1 ohms with a diode if you cut out the 18 ohm resistors, because the reverse breakdown of the LED's will be higher than the battery voltage so the LED's will block current from flowing back into the charger and discharging the cells.

  • @UpLateGeek
    @UpLateGeek Před rokem +18

    I dreaded working with SMD components for a long time. Partly because they're so tiny and my hands are a bit shaky, but also because it meant I'd have to buy a whole lot more components. But then I saw a few projects on the Interwebs that I wanted to build, but they were all SMD. So I bit the bullet and ordered the boards and parts, and gave it a go.
    To my surprise, it wasn't nearly as difficult as I thought. It didn't take long to get used to the tiny components, even with my unsteady hands. I even built one of Rasteri's weeCee tiny PCs, which required aligning 1.25mm twin row SMD headers within a fraction of a mm on four sides to fit the processor module.
    Now I've designed my own projects that use SMD parts, designed the boards got them manufactured and everything. I've even printed and etched my own home made boards using the toner transfer method. Basically the only reason I'd go for through hole over SMD is if I wanted to use a specific through hole part (potentiometer, header pins, specific IC that I already had in through hole version), or if I wanted the circuit to look vintage (I'm currently designing a clock that uses a vintage VFD display, housed in a wood and acrylic case that shows off both the VFD and the PCB).

  • @cameradoctor205
    @cameradoctor205 Před rokem +78

    When digital point and shoot cameras used AA batteries, customers were often impatient and wanted their batteries to charge fast !! ... there were a lot of 'Fast Chargers' sold, and I am sure they Nuked the poor NiMH cells ... I tried to sell a slower charger and a spare set of cells, but not everybody could be taught ;)

    • @senorcapitandiogenes2068
      @senorcapitandiogenes2068 Před rokem +16

      Can confirm. I might or might not own a charger that charges AA Nimh cells at 8 amps

    • @jkobain
      @jkobain Před rokem +5

      I can recall Dave @EEVblog showcasing and investigating a fast charger. IIRC, 4A per cell, or even more, since it is said NiMH can withstand it when done right.

    • @sigmasquadleader
      @sigmasquadleader Před rokem +7

      Photographers aren't really known for their intellect or practical skills, so it's no surprise the general public exposed to technology would fail just as professional and amateur photographers would.

    • @jkobain
      @jkobain Před rokem +10

      @@sigmasquadleader what an interesting opinion based on facts. Thank you!

    • @pauldzim
      @pauldzim Před rokem +3

      @@sigmasquadleader photography slander!

  • @DrRChandra
    @DrRChandra Před rokem +10

    I guess the Schottky diode is belt and suspenders, because the "D" in "LED" is for "diode"; the current should only go in one direction through either.

    • @bigclivedotcom
      @bigclivedotcom  Před rokem +7

      It was to allow for a future parallel resistor addition.

  • @Alloverthecarpet1
    @Alloverthecarpet1 Před rokem +16

    Your NiMh trickle charger was one of the first projects I did getting back into electronics this last year. I use portable radios pretty heavily in my day to day and having a set of batteries ready to go at all times is really convenient. Thanks for doing what you do!

  • @RJHElias
    @RJHElias Před rokem +1

    That solering tip looks like a elephant foot for smd soldering. Never the less, you do a great job Clive. I am a fan forever!

  • @daveedee3626
    @daveedee3626 Před rokem +1

    I've been waiting for this video since I bought a bunch of these dirt cheap chargers sometime last year. Thanks Clive.

  • @grantrennie
    @grantrennie Před rokem +10

    Thank you for another great video Clive, have a nice day and be well everyone

  • @maltoNitho
    @maltoNitho Před rokem +3

    What a lovely follow up! Just last weekend I was thinking about building your previous trickle charger… but instead I just ordered one of these and will just remove the resistor. Thanks as always for the entertaining and educational watch!

  • @GizmosWorkshop
    @GizmosWorkshop Před rokem +1

    I was taught electronics when I educated as a Radio TV Repair tech in the late 90s, and SMD was just a side notice.. Got my certificate and there was no work so I went into telecoms instead.
    Been there in various jobs since then, until recently when I started working in an electronics factory and Oh sweet lord this stuff is tiny.. My glasses need glasses for some of the stuff :D
    What I learned pretty early though, is get yourself a syringe of flux paste, and just jab that on there before you solder the component down, and also a sharper tip helps. The flux will really help spreading the heat, and the sharp tip will make it less messy.

  • @chaos.corner
    @chaos.corner Před rokem +20

    It could also be turned into a handy power supply if you were looking for easy battery swaps.

  • @panthony1525
    @panthony1525 Před rokem +2

    Would very much like to see you do a dedicated video on how to reverse engineer a circuit board, from analysing the board to producing a schematic diagram.

  • @wimwiddershins
    @wimwiddershins Před rokem +63

    Gotta like NiMH for being less fussy and a bit tougher than Lithium cells.

    • @edwardfletcher7790
      @edwardfletcher7790 Před rokem +6

      Also for being the correct voltage for all our gadgets 👍

    • @jimurrata6785
      @jimurrata6785 Před rokem +5

      _Mostly_ for being compatible with devices intended for alkaline batteries. 👍

    • @user-zz4to5kq1q
      @user-zz4to5kq1q Před rokem

      If the charging current is no too large, the excess energy on overcharged NiMh battery will be dissipated out as heat. Not easy to explose.

    • @mos8541
      @mos8541 Před rokem +2

      No I don't, keep your 1.2 volts if ur lucky, next someone gonna tell me benefits of those horrible nicads

    •  Před rokem +3

      @@mos8541 NiCd -> high-power performance at very low temperature. Sorry, couldn't resist. XD

  • @segamanxero
    @segamanxero Před rokem +1

    Was excited for this, I ordered from eBay what I thought was the same charger, but I got something with a slightly different PCB on it. PCB has a model number "MQ B-04". Traces are slightly different two 1.1 or 1 ohm coming off positive, the resistors seem swapped 22ohm in series with led and 150 going to positive contact. Resistor groupings on the board is different from your example, where resistors outside the first ones on the positive side input are placed around each positive battery terminal and led. Interesting with the differences between your example, and the one I got from eBay.

    • @MrTomasssh
      @MrTomasssh Před rokem

      I got one from AliExpress and expected the same. The one I got had the exact schematic as Clive drew on the previous video (one R parallel with an R and an LED). Different PCB layout and values though (1k in series with the LED and parallel to a 24R). I removed the 24R and now I wonder if using a 1k and LED in series with the cell even charges it at all. There is current flowing because the LEDs light up (quite well, actually)

  • @AMDRADEONRUBY
    @AMDRADEONRUBY Před rokem +9

    Eneloop batteries are my favorite lasting long and being reliable this charger looks very cheaply made lol

  • @coverfrequency2305
    @coverfrequency2305 Před rokem

    I really enjoy these cheap electronics teardowns. I've integrated cheap circuits into prototypes.

  • @johnbrandolini2915
    @johnbrandolini2915 Před rokem

    I'm glad you brought up the point that the modified charger was intended to "top off" charged batteries. Basically the idea is to provide just enough current to overcome the cells internal resistance. That's actually called maintenance charging. I designed a 12.6v gel cell charger based on a 7815 series regulator that provides it's output based on the state of the battery. The charging current will be 1 amp when the battery is discharged and will taper off to about 8 ma at full charge. I chose the 8 ma value based on the data sheet for the battery. The charger and battery are in an emergency lighting system I built almost 10 years ago. The battery has lived well beyond it's natural life thanks to maintenance charging.
    With regards to surface mount components, I would recommend getting a microscope to assist in placement especially for the 0805 and 0603 parts. I have a Mustool microscope that has it's own display and can magnify up to 600x. It wasn't that expensive- under $50 USD (41 GBP) on Amazon. As a radio amateur I receive the ARRL's QST magazine and a couple of years back they ran an article about using a PC cam as an alternate to a microscope. I tried it and it's doable but it is cumbersome and the magnification is limited. Solder paste is a much better alternative to fluxed solid solder as a dab will hold the part in place until you put pressure on it with tweezers. Also you get better control of the amount of solder on the pad. As to the type of tweezers the ceramic tipped ones are ok for passive components but not so good for actives such as MMICs where they might be subject to static damage. For that reason I have a grounded mat on my bench and use conductive tweezers when I'm working with actives. My workspace is a scaled down version of what I used to use back before I retired.
    Finally, a schottky diode would have been my first choice since it has a forward voltage drop of about .1v as opposed to .6v for a standard PN junction diode. At 40ma the diode will dissipate only about 4mw. Later.

  • @simplygame5530
    @simplygame5530 Před rokem +1

    Saw the notification and I was like "oh this is going to be fun"!

  • @Neovo.Geesink
    @Neovo.Geesink Před rokem +1

    Yet another undocumented benefit: You can use it to balance cells which are to be used in series in an applience by just letting them in there after charging, and disconnect only the USB plug. After a few days a quick boost by topping them up, and they should be balanced.

  • @novids4938
    @novids4938 Před rokem +1

    I'd think the LED's would prevent discharge of the cells after removing the 18 ohm resistors. So the hack could be done with even less effort.

  • @DigitalIP
    @DigitalIP Před rokem +1

    I'm glad you mentioned the potential resistance of the USB cable. I'm also glad you mentioned reverse discharging because thats exactly what my TOMO M4 18650 power bank does that i got in 2019, so after charging 18650s with it if i dont plan on using the power bank i started removing them to stop that from happening.

  • @binaryguru
    @binaryguru Před rokem +18

    USB 2.0 can only support 500mA anyway so I think it makes sense that the charger does not go above that.

    • @jkobain
      @jkobain Před rokem +4

      And some dirty wall adapters can't even supply this much, eh.

    • @Globaltalentgt
      @Globaltalentgt Před rokem

      ninaryguru Hey What's up

    • @Tomlinsky
      @Tomlinsky Před rokem +3

      That's if the current to be passed from a 'Host' has been negotiated via protocol with an attached device. Most USB PSU's aren't designed as compliant USB Hosts and never enumerate with an attached device and will happily pass-thru whatever current is available depending on the design of whatever is attached.

  • @fluffyblue4006
    @fluffyblue4006 Před rokem +1

    I converted a GP 'overnight' charger for 2x2 cells into a 4x1 cells trickle charger. Mainly because the unit in its original shape could not charge 1 or 3 cells, but also because it slightly warmed up the cells when using it as a trickle charger.

  • @gregorythomas333
    @gregorythomas333 Před rokem +6

    I use Nitecore chargers...single, dual & quad...for my batteries...Eneloop AA & AAA...plus Samsung 18650's.
    They work great and have not failed to charge nor have they overcharged to date.

    • @Globaltalentgt
      @Globaltalentgt Před rokem

      Let's do this come on ❤❤

    • @pincombe
      @pincombe Před rokem

      my nitecore charger has a ton of coilwhine tho so much so I only pull it out when I really need to

  • @beefaroni4733
    @beefaroni4733 Před rokem

    all these weirdos telling me i need tweezers and a magnifying lens and a tiny soldering tip meanwhile you're out here rawdogging it with a standard tip and just wiping them off. well, guess i learned something today.

  • @steviejanssen
    @steviejanssen Před rokem

    Clive, you made my day, I also defied using smd´s for years😂
    Being an electronician since 1990... love your videos, you´re the best. 73´s.

  • @ziginox
    @ziginox Před rokem +3

    Clive, I appreciate the recommendation on the ceramic tweezers. I grabbed some a while back after you mentioned them in another video, and they're great! They work nicely for hot air soldering of SMD stuff, too. Mine use black ceramic, supposedly ESD-safe, but I don't know if I trust that.

  • @DirkFedermann
    @DirkFedermann Před rokem +1

    that is funny that you bring out a NIMH charger video again.
    I recently made a charger using one of your videos. Only things that I changed was USB-C compatible with the 5.1k resistors and I made one bay fast(er) charging with a lower resistor value.
    With shipping and making only one, it still came to about the same price as a cheap charger on amazon.

  • @PaulSteMarie
    @PaulSteMarie Před rokem +11

    I would assume that the current draw had been limited to 500mA, which is the default limit for USB in the absence of shorted data lines, weird resistor combinations, or current negotiation.

    • @andygozzo72
      @andygozzo72 Před rokem +1

      there is no 'negotiation', is just a straight resistive current limit circuit, similar to most mains powered nicad/nimh chargers although one i have is more like the previous 'rougher' one, relying on the resistance of the transformer secondary wire to limit current !! you could even use a small bulb as current limiter, i've done a few times, for this a 6v 0.04a in each channel would do nicely , although not easy to find, 0.06a ones bit easier

    • @demef758
      @demef758 Před rokem

      The original USB spec was 100 mA (the pre-negotiated value) and 500 mA (the post negotiated value). The problem with that is that SOMETHING had to be able to limit the currents, and that semiconductor was $$$. Most of the Asian-supplied PCs were focused on low cost, so they omitted the current-limiting circuitry to save money. You often had the PC's raw 5V supply wired directly to the VBUS leads on the USB ports. In time, most PC guys threw up their hands and said "why bother?" and current was no longer limited. Now you have little 5V 1A and 2A wall warts that have no real current limiting to them.
      I recall long ago when the PC guys inquired of Apple what it would cost to add Apple's Firewire ports on their machines. Apple's reply was $1/port. They were outraged, saying that a USB port's cost was about 1/4th of that. Apple then tried to backpeddle and lower the licensing price, but the damage was done. How many PCs did you see with Firewire ports (before Apple killed Firewire)? My point being that PC manufacturers are extremely cost-conscious.

  • @jkobain
    @jkobain Před rokem +8

    By the way, they sell 8W rechargeable soldering irons based on a similar to EVOD devices design and 510 screw-on soldering pieces (those you showcased before). They aren't very powerful and don't last much off of full charge; yet, they can save you in the field / during a power outage.
    Moreover, they started to sell like more powerful soldering pieces with a set of changeable tips and spare heating elements, and bigger announced heating power, which could make them a better solutions for owners of more powerful battery mods. Have you tried these ones yet? I'm asking because even these eight-watts things are not as bad as I expected, and if you ever happen to get yourself the newer version, it'd be quite interesting to hear your review.

    • @bigclivedotcom
      @bigclivedotcom  Před rokem +5

      I have made a couple of videos about the vape based soldering irons.

  • @ejonesss
    @ejonesss Před rokem +1

    for nicd and nimh that circuitry is not bad at all .
    in the 80s often the dc from the power supply could just go to the cells and that was fine for charging nicd and nimh.
    today's lithium even the lifepo4 and lto variants require more advanced circuitry than a simple resistor to limit current.

  • @elk3909
    @elk3909 Před rokem +1

    im so glad im ultra near sighted. ive never needed a magnify glass since my eyes have a focal distance of 1.5 inches. in electronics class i was the only one able to do smd chips and ics without a microscope. so the teachers had to debate how to grade me since i had a advantage over all the other students.

    • @TravisTev
      @TravisTev Před rokem

      My eyesight is the same way. I think my main concern if I got into electronics would just be protecting my eyes when working with tools at such close distances.

    • @johnbrandolini2915
      @johnbrandolini2915 Před rokem

      Being near sighted myself I have always had an advantage when working with small parts but take it from me when you get down to 0402 pitch and smaller parts you will need a microscope. The 01005 parts are not much bigger than a grain of sand.

  • @zomgsako
    @zomgsako Před rokem

    Back in the days then I was young and naive I "hacked" one of those spring loaded chargers, basically threw out all the circuitry and just added a connector to hook it to a RC battery charger. I needed to charge 4 eneloop at a time (for Tamiya mini4wd models). Turns out the springs can't bear a 2A charge, they get super hot and melt. Lesson learned!

  • @nickolaswilliams935
    @nickolaswilliams935 Před rokem

    The schottky diode is actually superfluous, the LED’s will provide reverse protection on their own. Solder bridge the schottky, you’ll get a slight bump in charge current to boot.

  • @NaturallyCuriousUK
    @NaturallyCuriousUK Před rokem

    Delightful. Good to see that surface mount is not so scary, and a nice tool tip about the tweezers at the end. I have actually built a 3 board version of the Simple NiMH battery charger (with PCB files) Big Clive showed us how to make. 👍🙂👍

  • @PeterShipley1
    @PeterShipley1 Před rokem +2

    I'm with you about Surface Mount, if it's a simple circuit I prefer the larger traditional components

  • @u.e.u.e.
    @u.e.u.e. Před rokem +2

    It's *amazing* , how you recognise with your knowledge a faulty/not ideal product, analyse the manufacturer's mistake(s) and improve the product to your needs with just some touches with the soldering iron and one available component out of the box! 😃👍

    • @jkobain
      @jkobain Před rokem +1

      Clive is a gem.

    • @u.e.u.e.
      @u.e.u.e. Před rokem +1

      @@jkobain Yesss! 😃👍

    • @jkobain
      @jkobain Před rokem

      @@u.e.u.e. he taught me a lot, while simply doing things he himself enjoys and talking whatever he likes. The way he presents knowledge and technicalities is just priceless and easy.

    • @bigclivedotcom
      @bigclivedotcom  Před rokem +1

      I'm just feeling awkward and humble now.

  • @Richardincancale
    @Richardincancale Před rokem +3

    6:28 If you snipped out the 20 ohm resistors the LEDs would act as diodes and stop the discharge anyway wouldn’t they?

  • @graemebrumfitt6668
    @graemebrumfitt6668 Před rokem

    Rite Big Dude, Neat little hack. I was using my ceramic tweezers the other day and thought, wonder if Clive still uses his as I haven't seen them for a while! Love mine so thanks for pointing them out. TFS, GB :)

  • @thaphreak
    @thaphreak Před rokem +3

    They totally saw your video and made a revision 😂

  • @Nono-hk3is
    @Nono-hk3is Před rokem +1

    As someone who did the same a few years ago, I've enjoyed watching you come to terms with surface mount over the past few years.

  • @craignehring
    @craignehring Před rokem +2

    Rightyo? Trying to sound cool... Nice work there master Clive

  • @jkobain
    @jkobain Před rokem +1

    I do have some NiMH AA and AAA cells. For instance, I've been using NiMH AA ones in my wireless mouse every day for more than ten years already; and I can't really tell how many days or weeks it takes to discharge one cell. The mouse has a boost circuit in it, so it drains the cell quicker, but doesn't require two (thus neither weighs significantly more, nor falls to using two AAAs).
    Those cells I bought before switching to this wireless mouse are still with me, and I honestly can't really even tell which of them all were bought a bit later; maybe only by date codes, or measuring their capacity degradation. I used to think NiCd cells are better for low-current applications: I've been told they have smaller self-discharge current. But, again, after more than ten years of using NiMH cells every day, I can't complain.
    Initially, I didn't really like Lithium cells when they started appearing here and there, I was even more dumb and incompetent than I am now (surprisingly, it was possible!), plus they weren't as good as they can be today. Nowadays, I still like NiMH cells, already like Lithium cells (recently found three discarded POD units, one of them is rechargeable and supports cartridges with e-liquid and mesh heater), but my observations show that NiCd cells are leaving us: they suffer from memory effects similar to those of NiMH ones, they chemically degrade like faster, and their capacity per weight and per volume haven't been improved lately by the manufacturers.
    I may be wrong (and I often tend to be), but this is my personal experience.

  • @edwardfletcher7790
    @edwardfletcher7790 Před rokem +5

    Those L shaped sliding contacts are the only way to do reliable charging. A simple spring always heats up and fails.

    • @rogierius
      @rogierius Před rokem

      Noob here, but the L-shape battery holding mechanism has a spring as well. Or am I missing something obvious here?

    • @edwardfletcher7790
      @edwardfletcher7790 Před rokem +1

      @@rogierius The standard battery holder springs tend to act as induction loops (like your stove).
      This heavy L shape plate & "spring" is designed to accept multiple battery sizes and avoid heating.

  • @Nozinbonsai
    @Nozinbonsai Před rokem

    Ahh Clive turns something I can't understand into something I can't understand.
    I feel relieved from my own stupidity.

  • @plageran
    @plageran Před rokem

    a skill i have yet to master, it's fun to play around on old phone chargers

  • @JohnClulow
    @JohnClulow Před rokem +2

    Many useful tips (as usual). Thanks!

  • @joystickmusic
    @joystickmusic Před rokem +1

    The schottky diode is not so needed, because the LEDs also are in series with the batteries, unless you do not trust them to block the back flow. And in your drawing, you did not cross out the two 5Ω1 resistors

  • @spinb
    @spinb Před rokem +1

    That USB Buck Booster sure looks interesting.

  • @Mr.Unacceptable
    @Mr.Unacceptable Před rokem +4

    I would rather use surface mount than through hole. Much easier to work with once you have a system.

  • @Megamannen
    @Megamannen Před rokem +1

    USB2 spec only allows 500mA current draw. Probably that's why it's limited to 450

  • @nicolassales8679
    @nicolassales8679 Před rokem

    Clive, thanks for the regular reminders to never fly in a Chinese built aircraft!

  • @CBitsTech
    @CBitsTech Před rokem +5

    Links to things like your flux and tweezers would be handy please. They might earn you a few pennies too if they're Amazon or eBay affiliate links.

  • @aharkness5657
    @aharkness5657 Před rokem

    My first thought about the big and little resistor in parallel is that the design was meant to be used with one or the other depending on if you need extra dissipation or can go with one size of resistor. Someone just decided to populate both in the end and maybe double the value to end up with the 2.something ohms.

  • @Zools_tube
    @Zools_tube Před rokem

    I'll share my tip for surface mount components, you need a stick of paper glue and a cocktail stick.
    Put a tiny bit of glue in the middle of the component with one end of the stick & place it on the pcb. Then using the other end apply a little pressure to keep it there while you solder it.

  • @jkobain
    @jkobain Před rokem

    I was going to mention it will do its best at revitalizing «dead» NiMH cells your smart chargers won't agree to recognize, and it will recover them in the safest manner possible.
    But you said it right away.

  • @martinclemesha4794
    @martinclemesha4794 Před rokem

    Just the everyday kind of project I find very interesting.

  • @johnsonlam
    @johnsonlam Před rokem +5

    Nice hack, thanks.

  • @phonotical
    @phonotical Před rokem

    Whoever designed that cardboard box was clearly a doctor who fan...

  • @acmefixer1
    @acmefixer1 Před rokem +4

    Clive, why don't you do a video on this? Please do!
    I thought about modifying the cheap one like this that holds 3 cells. Instead of 3 in parallel, change them to 3 in series, so it would take maybe 50 mA total. The idea was to charge them using a small 5V solar panel, and leave them in a window, constantly trickle charging. Whenever a cell was needed, just pull it out and it will *always* be fully charged.
    Yes, I thought about the empty cell holder would prevent the remaining cells from being charged. There could be more than one solution to this. One is to connect two 1N4003 rectifier diodes in series across each cell holder, so if the voltage is greater than 1.2V it will bypass around the cell. It might need a third Schottky diode in series to make the voltage 1.5V. or it might be better to use the LEDs on the charger, and a resistor in parallel.
    Another solution if you don't want the diodes inside is to cut a length of 1/2" or 13mm wood dowel to the length of a AA cell, drill holes in the ends and screw small sheet metal screws in. Then connect the diodes across the screws. Mark the ends plus and minus and now you have a dummy battery that will pass current to the remaining cells. The only downside is that it's something that might be misplaced if it's left out most of the time.
    The idea is to make a few of these that will keep the dozen or more Ni-MH cells that I have, that will always be trickle charged using solar cells.

    • @eone2345
      @eone2345 Před rokem +1

      Charger in series will be much more complicated and expensive compared to parallel for removable battery. For example you will need more complicated circuit like BMS that will balance the voltage of batteries and additional solar panel for much higher voltage and buck circuit to stabilize the output voltage.
      I took this into consideration when designing solar light for my night light. Instead of using series connection that will requires me to add additonal solar panel, I simply design them in parallel then boost out the output to 12volt using boost converter. By doing that, I save money on additional solar panel as well as BMS.
      Why additional solar panel? Because solar panel output is variable throughout the day. You need higher voltage for reliable charging operation.

    • @andygozzo72
      @andygozzo72 Před rokem +1

      i have a cheapo one like that, its series 'as is', clive reviewed one some years back, circuit is not surprisingly rather nasty and relies partially on the resistance of the copper covered aluminium cable to limit the current 😁 current 'regulator' plus indicator is in the usb plug

  • @Sazoji
    @Sazoji Před rokem +3

    I have a NiZn charger that's pretty advanced, has some form of monitoring or a fake way with dual-color LEDs

    • @jkobain
      @jkobain Před rokem +1

      They usually have red and green in parallel, but green LED has higher forward voltage drop and lights up only when the current going into the battery drops low. They either connect such an indicator in parallel with the cell, or through a transistor, or control it via some IC.

  • @twocvbloke
    @twocvbloke Před rokem +1

    The other issue with letting batteries sit at a higher current is the rapid expulsion of electrolyte, when they go bang, cos someone tried charging a battery on the wrong supply and soiled themselves when said battery went pop... :P

  • @Njazmo
    @Njazmo Před rokem

    Maybe the first resistors was a voltage divider, so you don't push something like 4 volts into a 1.2V cell, but you can easily measure things, or calculate.

  • @h-leath6339
    @h-leath6339 Před rokem

    Ghhaaaaahhhh! I hate SMC. Inappropriately small. You are a master Mr. Clive!

  • @PsiQ
    @PsiQ Před rokem

    Never checked how those springcontacts worked. A lot simpler than i expected.
    This is one of those products were a bit more thought into the components, without any higher cost, would make it a good product.

  • @jkobain
    @jkobain Před rokem +3

    After watching some of your videos, I decided to try simple kits (or suites, as they call it); and initially I didn't feel good about those with SMD components, but I decided that if you said trying will help learning, one should try and see for themselves, right? After a very brief period, I came to a conclusion that if you solder manually and use lead-based solder with a low melting point, you can do and undo like 0805 or 0603, or SOT-23 quite easily, even with a «traditional» soldering iron. Since then, I don't fear SMD that much. Thank you a lot, again!
    SMD components are also cheaper and more compact. ^_^

    • @Globaltalentgt
      @Globaltalentgt Před rokem +1

      Janus Kobain hey What's up bro

    • @jimmybrad156
      @jimmybrad156 Před rokem +2

      I get 1206 size SMD components where I can; manages to fit on 0.1" (2.54mm) veroboard hole spacing not too bad.

    • @jkobain
      @jkobain Před rokem +2

      @@jimmybrad156 I prefer 0805 ans 0603, since they fit right across the edges of the contact pads around the holes. And I chose to tombstone several 0805 resistors on one board - only because I decided it will fit even better this way.

    • @jimmybrad156
      @jimmybrad156 Před rokem +2

      @@jkobain What I really meant is that 1206's are a little easier to keep a hold of lol

    • @jkobain
      @jkobain Před rokem +1

      @@jimmybrad156 and the numbers are bigger to read, lol. ;D
      Although caps are blank anyway…

  • @maltoNitho
    @maltoNitho Před rokem

    11:47 “a very very long time” is between eight and nine days. Adding here since I did the math.
    2000mAh / 9mA = 222.22 hours (9.2 days)
    2000mAh / 10mA = 200 hours (8.3 days)

  • @mikepanchaud1
    @mikepanchaud1 Před rokem

    The diode at 6:28 should be in series, not in parallel to the 2 resistors. Reverse current will still flow through the 2 parallel resistors. As others have said if the 18 ohm resistors are removed the extra diode isn't needed at all as the LEDs will do the job.

    • @bigclivedotcom
      @bigclivedotcom  Před rokem +1

      I should have scribbled over the resistors in the schematic. I was just showing where it would go in the circuit to replace them.

  • @nucleochemist
    @nucleochemist Před rokem

    Anyone who wants a good multipurpose and multifunction charger just get a BT-C3100 or newer and you won't have to solder, modify, or reverse engineer anything. I use it for testing battery capacities and topping Ni-MH and Li-ion daily.

  • @joshwalker5605
    @joshwalker5605 Před rokem

    Content free comment to drive engagement for my favorite channels

  • @1kreature
    @1kreature Před rokem

    By using the LED's as the only current path it effectively adds a diode for each cell as well, making a fully charged cell not able to "charge" the other cells when inserted. All charge must come from the supply.

    • @artok3897
      @artok3897 Před rokem

      Hence, changing the resistors for the scottky diode was unnecessary.

  • @alldave
    @alldave Před rokem +1

    So the back feed is actually a secret feature to drain the batteries for storage 😮

  • @Bleats_Sinodai
    @Bleats_Sinodai Před rokem +1

    The resistor in parallel with the resistor and LED is an old trick, I've seen it used a few times for charging batteries in various equipments from my time working maintenance at the local hospital.

    • @Mark1024MAK
      @Mark1024MAK Před rokem

      Yeah, I’ve seen that arrangement used in domestic and industrial Ni-Cad chargers from the 1980s onwards.

  • @Netties8266
    @Netties8266 Před rokem +2

    That bottle of flux looks like my urine sample I gave to the doctor today.

    • @brucepickess8097
      @brucepickess8097 Před rokem +1

      Have you checked to see if it's suitable for soldering ?although if it is I'm not sure that you could stand the stench.😏

    • @Netties8266
      @Netties8266 Před rokem +2

      I wear an old ww2 mask when using it. Come back after a day and the joint is corroded. Gives it an antique finish and Tom cats around. That way the project also gets a cat scan at the same time. Win win all around.

    • @brucepickess8097
      @brucepickess8097 Před rokem

      @@Netties8266 Ok, so urine is fine, however let's not use it all of the time. 👍😏

  • @LoftechUK
    @LoftechUK Před rokem

    It’s not rocket science but you do make it clear.

  • @d.t.4523
    @d.t.4523 Před rokem +1

    Cool. Great improvement. Are they available from Big Clive Industrial Electronics Corporation yet? I'll take 2. Keep working. Good luck! 👍

  • @piconano
    @piconano Před rokem

    I'd be very interested to see the guts of an Ikea charger that looks like this one.
    This one looks like it was made by one dude in his basement!

  • @jmr
    @jmr Před rokem +1

    I "Rescue" cells with an alligator clip and another cell in parallel for a few seconds. Just enough to trick my smart charger. 😂

  • @davebrooks69
    @davebrooks69 Před rokem +2

    3DQF... added to approved suppliers list.

  • @nomusicrc
    @nomusicrc Před rokem +1

    I have an 8 cell GE charger and a four cell GE charger I have so many nickel metal hydride batteries that I bought another eight and four cell off of eBay

  • @sarkybugger5009
    @sarkybugger5009 Před rokem +1

    I'll put you down for another revisit in 2028, Clive. We'll see if they have incorporated your latest improvements. 😃

    • @bigclivedotcom
      @bigclivedotcom  Před rokem +3

      There's a revisit coming up that managed to reduce the component count to 4 including the charge LED.

  • @berntolovhellstrom8891
    @berntolovhellstrom8891 Před rokem +1

    None of the common chargers can charge Li-ion for storage as they shouldn't be charged too high and not discharged too low. This is an ignored feature, also in expensive chargers.

  • @merwindor
    @merwindor Před rokem +2

    The case looks so trashy I half expected a fake ioniser to be stuffed in there just for old times sake.

  • @cerulyse
    @cerulyse Před rokem

    I've collected several from car boot sales 50p and that show you when people buying essentially unserviceable products containing lithium ion

  • @DogsLife12
    @DogsLife12 Před rokem

    Through hole is the new point to point.

  • @legionofanon
    @legionofanon Před rokem

    If you dont mind spending a little bit of cash, I really like the Nitecore battery chargers. they have a much longer spring contact so its capable of charging AA, AAA, and 18650 batteries. I think I charged a slightly larger battery cell than the 18650 for one vape I had, but I dont recall whats its number is.
    The nitecore has 2 and 4 battery bay options and the one I have has a nice lcd screen for showing charge rate and battery voltage and estimated charge level of 0 to 4 bars

  • @pintokitkat
    @pintokitkat Před rokem

    I resisted smc for years to until I realised they did away with drilling and I could do all the soldering at once on a home made heat pad. Forehead slap followed.

  • @ThatJay283
    @ThatJay283 Před rokem

    maybe the manufacturers will see this video, and change the circuit to be like this. except without an extra diode, just LEDs as the discharge protection

  • @andyhill242
    @andyhill242 Před rokem +1

    I think they stole your design there Clive!

  • @Sentinel-1
    @Sentinel-1 Před rokem +1

    Considering that a typical 2500 mAh AA NiMH cell will take charge for more than 10 days at 10 mA, this is not a very reasonable hack. 😅
    It definitely needs some digital or analog circuit to change the charging current from high to low when nearly charged voltage threshold will be reached. This could be an interesting project, by the way.

    • @brucepickess8097
      @brucepickess8097 Před rokem +1

      Hi, yes my thought as well.😏👍

    • @bigclivedotcom
      @bigclivedotcom  Před rokem +1

      It's for where you have applications using NiMh cells that need changed every few weeks or more, so that a fully charged set is always available.

  • @finger351
    @finger351 Před rokem

    I bought the same ceramic tipped tweezers when I tried surface mount witchcraft, then realised I'm not a witch when it took 45 minutes to solder 6 resistors. Bollocks to that, I'll stick with through hole.

  • @Mike-H_UK
    @Mike-H_UK Před rokem

    There are some studies out there (which CZcams won't let me link) that shows that even for very low trickle charge currents (the study went down to 20mA) there is a reduction in cell capacity after 100+ cycles with the low self-discharge NiMH cells. I imagine that 10mA will be less stressful than these tests, but not perfect. I charge AA cells at 25-30mA because I built my charger before I knew this, and and this is a compromise between damaging cells and charging them in a reasonable timescale.

    • @johnbrandolini2915
      @johnbrandolini2915 Před rokem +1

      Depending on what your intended use is a maintenance charging system will extend the life of the cell. When I designed my 12.6v gel cell emergency lighting system I went to the battery manufacturer's and looked up the battery's specs. Basically a maintenance charge is the amount of current needed to overcome the internal resistance of the battery thus balancing out the battery's propensity to self-discharge. In my case the maintenance charge current worked out to around 8 ma which was just enough to keep the battery fully charged. After the battery kicked in during a power outage and the power was restored the charger would kick in at about 800ma until the charge was restored and taper off to the maintenance level. I built my system about 8 years ago and the battery is still performing as if it was new.

    • @Mike-H_UK
      @Mike-H_UK Před rokem

      @@johnbrandolini2915 Yes. I think that the problem is with the very low leakage NiMH cells, the safe maintenance charge level is so low (

  • @1kreature
    @1kreature Před rokem

    Wooooh! Ceramic tweezers! Nice!

  • @jimmybrad156
    @jimmybrad156 Před rokem +1

    Just got a BT-C3100; not bad for the price, but it trickles my LSD eneloops after charging whether I like it or not. It should give the option to disable trickle charging.

  • @mattclement4548
    @mattclement4548 Před rokem +1

    I bought the exact same sh@t heap usb charging is useless and I don’t find the light changes yet. But I used google translate on the manual u get more specs and it even says charging via USB can get hot! And I think in English it say but also says to run at DC only at 5v 1amp DC plug like a small I phone charger I been using quicker results but still stupid cause u still have to check with multimeter! It’s LATE Matt here from Australia and I’ve been watching for ages just very late again on subscribing I’ve done that now thanks for doing this video

    • @mattclement4548
      @mattclement4548 Před rokem

      Mind turn out probably was the first heap u bought mine has some dumb gap between 2nd an 3rd battery positions but now I reckon I mod mine! Cheers mate

    • @andygozzo72
      @andygozzo72 Před rokem

      sounds like it needs checking/modding

    • @mattclement4548
      @mattclement4548 Před rokem

      Sorry I lied just a different and urs looked lots of English I have lot Chinese and a tiny bit of info in English more but not much in instructions

  • @robinsattahip2376
    @robinsattahip2376 Před rokem +1

    I got the urge to take mine apart while watching the video, it has 240vac input but has a full wave rectifier and even a fuse. Who can ask for anything more for about $5? It works well.

    • @bigclivedotcom
      @bigclivedotcom  Před rokem +2

      Be aware that the cheap mains voltage ones can sometimes have poor electrical isolation.

    • @jimmybrad156
      @jimmybrad156 Před rokem +1

      The $10 ikea ones are safer for you and your cells :)

  • @richardbriansmith8562

    Awesome Video big clive