The green boxes are really nice. You're definitely paying for their intricate design and build but you get quality hinges, latches and springs. I firstly bought 50 of the mini "IC" blue boxes; I wish I didn't now, they're too small to be practical. I can fit about 10 8 pin DIPs in one at a squeeze. It's more worth using the size in the video despite price. I've ordered 40 so far to put resistors in, from SMD to 1W and 10 of the larger pink square ones for mixes of various components such as diodes and the like.
Running the ground through the DC input of the dummy load means you are putting a high current through a path designed for low current. You might blow a track on the pcb doing that.
I have that step up/down and pretty much like it. It can be recalibrated, has profiles and seems safe to short. But yours seems indeed a bit strange. Not bat for that price. But your noise measurements make me wonder if it is really safe to use on sensitive devices even when those huge spikes probably come from your load. I should probably get a scope now.
I have the same DC-DC converter in the shed. You may have seen it? I get inductor ringing at various points in its range but I've been pleased with it as a unit. There is a bit of noise on the output, but I think the two volts you were seeing (and frequency) was probably the DC load switching in and out don't you? Perhaps the Minghe was struggling with the transient response? I'll have a go with mine if you like and report back.
I have a whole ton of those little stepper motors, bought with the intention of playing around with some robotics, sadly they're not particularly powerful even with the gearing. If you're planning on getting more and doing some projects with them, I recommend getting the ULN2803 as a driver IC instead of the standard ULN2003 that's used on the typical driver modules that come with them on ebay. the ULN2803 has 8 output pins so can drive two motors from one chip, instead of the 7 pins on the ULN2003.
I have one of those buck boosts you opened at the start, and it works really well except when plugging I plug it in, the output spikes quite horribly high before realising it should be off :/
I wonder if the DC-DC converter could be improved by having an adjustable voltage regulator on the output instead. The voltage regulator would bring it down cleanly to the desired voltage and the boost converter would bring the input voltage up to just above what the regulator needs. That way, maybe, you could get the best of both worlds. Clean output with the efficiency of a switch mode power supply.
Bought the Boost Buck PSU myself a while back, on my unit the inductor noise is only noticable when pushing the output to 34v+ Didn't see many dodgy misaligned components as you do. No extra capacitor as well :p
Really interesting video! If you ever plan to use the boost/buck converter continuously the "squealing" might pose a rather big problem though, because it means the windings are moving slightly which will slowly rub off the isolating lacquer. In general this sound is a sign of bad design... Just to keep in mind.
These 28BYJ-48 stepper motors can be hacked to bipolar (they are unipolar) which adds alot of torque to them, I used them with this hack to build a 3d printer, feel free to test the hack out for a video if you want to.
On the Step-Up/Down converter: shouldn't there be a "voltage gap" in the middle, around the voltage of your input? So for example if you're putting in 13.5V (I can't remember the exact number you said), shouldn't it only be able to go down to do, let's say, 0-12.5V and 14.5V-max? Because there's always a minimum difference when it steps up or down? When you were scrolling through the voltages it didn't ever seem to jump, and it seemed to let you set the exact voltage you had coming in. But then maybe if you try to actually use that voltage it will change it?
When buying those boxes, make sure that you buy same brand as you have three, WenTai, they works well. There are others that looks exactly same, but are totally rubbish. (I think the one Adafruit also sells are wentai). But, ESD?, nah, only the black ones are antistatic I think.
I bought those component trays some time ago - for my resistors. There were sticky paper tags on some lids. When I tried to wash off the glue residue, I found that the plastic of the lids degrades and will easily shatter after being exposed to isopropyl alcohol. Please can you try this on you batch? Also, the fit of may containers is not the best. Do you share that experience?
I just bought 50 of the green ones, luckily they were all packaged seperately, without any stickers on them, except one. Isopropyl alcohol didn't have any effect on that one. The fit really isn't the best on some of them, but at least the fit is not too loose. Also, the opening mechanism on some of them seems to be stuck, did you experience that too?
maybe i got knock-offs, but they look exactly like the ones here. the clear part of mine gets brittle after contact with alcohol (and showing some fine cracquelure). yes, some mechanisms were stuck. the hinges do break off easily. i have the smaller version (third width) too. both combine well but the fit can be very firm.
Hey julian, you're videos are boss, i was wondering if you fancied doing a themed post bag on wireless arduino interfaces? I'm in the process of building a painfully complex arduino/stepper thing and trying to settle on BT or 433 or other options ? cheers
The resistor storage box look much better then the crap i purchased from China. Obviously the unit was quite cheap but its locking mechanism was so flimsy that the doors will open by a modrate shake spilling all the components. Can anyone suggest better options available in 2022 for resistor/chip storage ?
Do you get many faulty products from Banggood? My first purchase (a LiPo Battery) is faulty, only a couple of quid, but asked for a refund, taken 3 weeks so far. A bit reluctant to buy anything more expensive...like over 3 quid :-)
You aren't using the DC Load correctly. It is a "4-wire unit", and you need to connect the other 2 (voltage) cables to the small white connector in front of the load (amperage) connectors on the right side.
Hey Julian, I just found a power bank, and I wonder if you have heard of it. It is the Luxa2 41600mah power bank and it is "the largest power bank in the world", and I'm curious if the 41,600mah is a complete lie or if it is true. It has good reviews and people say it lasts forever charging their phones but this thing only measures 3.9'' square.
+Keagan Knapp It looks genuine enough, but with all that stored energy it's a shame it only has USB outputs. A multi-voltage output would be useful on that thing.
+Julian Ilett I was thinking the same thing. I'm going to parallel up a couple (if not all 3) of the 2A ports and see if I can run a small boost converter off of it, and while I'm at it replace the blue leds with a few warm white ones if I can get the case open.
+Ray Kent I wish I could tell you I knew, but I do remember using a high powered usb device, what it was exactly I do not recall, but it used 2 male usb cords for power. I will take the power bank apart when I get it to make sure nothing is out the ordinary on the 2A ports.
Quick google search says they use 16 LG cells in there, and another search points to LGs 18650 powerbank-ey type cells to be around 2600mah. So yeah seems legit. Like Julian said though, shame it's only got USB. E: Seems like they use these www.batteryspace.com/lg-lithium-nmc-18650-rechargeable-cell-3-7v-2600mah-9-62wh---icr18650b4-un38-3-passed.aspx
+Adam Stewardson Several reasons: much bigger range of stuff on eBay.com - Patreon donations are in dollars - US audience is probably bigger than UK audience.
+Adam Stewardson Julian has additional reasons, but... You can get any item from any of the country specific pages, they are (finally) pretty much identical in functionality. The main difference is that sellers can select on which pages to list their items and you won't find items on the country pages even when you know the exact item name, if the seller didn't list it for that country. But you can enter any item id (found on ebay.com for example) into the search bar of a country page and it will get you to the specific item even if the item isn't listed for that country and show the according currency, if you don't want to convert it yourself. I think ebay.com is the page where all items are always listed. There's really not much point in using your "local" page (in fact many of the chinese seller's shops are totally empty on the ebay.de page for example, while having 1000s of items on ebay.com).
Quality control does not exists in most of these places, unfortunately. Often, one needs to resolder/realign components. Then , there is piss-poor packaging , items arrive damaged or unusable. Great shame though, China is yet to learn importance of product quality.
they thrive off cutting all corners to lower costs, we would not be able to buy half the cheap electronics if they suddenly decided to implement quality control
+Suraj Grewal Actually a preety cool idea, I think I have to save my tic tac boxes from now on. But man, 15 cents?! where I live it's more like 1 buck 15 ....
+Chris Ellingson I once had a solid capacitor exploded very close to my eye from a cheap DC to DC converter!! It starting making a weird noise so I held it into be face to hear it better, then BANG!!
I will make sure I don't buy one of those DC Converters lol - not unless I need extra parts and want to practice resoldering - that's just horrible quality even from China.
+Digger D Can someone start posting video's of item's like this that are better quality and not made in China, but at similar same prices. On UA-cam there's so much hate for cheap non big brand Chinese made stuff, It's time for someone to show us a long welcomed alternative :-)
That component in the inducter probably was to reduce the squealing. :D
Nah. Just a Freebie! :-)
The green boxes are really nice. You're definitely paying for their intricate design and build but you get quality hinges, latches and springs.
I firstly bought 50 of the mini "IC" blue boxes; I wish I didn't now, they're too small to be practical. I can fit about 10 8 pin DIPs in one at a squeeze. It's more worth using the size in the video despite price. I've ordered 40 so far to put resistors in, from SMD to 1W and 10 of the larger pink square ones for mixes of various components such as diodes and the like.
the spring mechanism on the boxes are for fast opening with tweezers when working with smt
Running the ground through the DC input of the dummy load means you are putting a high current through a path designed for low current. You might blow a track on the pcb doing that.
I have that step up/down and pretty much like it. It can be recalibrated, has profiles and seems safe to short.
But yours seems indeed a bit strange. Not bat for that price. But your noise measurements make me wonder if it is really safe to use on sensitive devices even when those huge spikes probably come from your load. I should probably get a scope now.
I have the same DC-DC converter in the shed. You may have seen it? I get inductor ringing at various points in its range but I've been pleased with it as a unit. There is a bit of noise on the output, but I think the two volts you were seeing (and frequency) was probably the DC load switching in and out don't you? Perhaps the Minghe was struggling with the transient response? I'll have a go with mine if you like and report back.
I have a whole ton of those little stepper motors, bought with the intention of playing around with some robotics, sadly they're not particularly powerful even with the gearing. If you're planning on getting more and doing some projects with them, I recommend getting the ULN2803 as a driver IC instead of the standard ULN2003 that's used on the typical driver modules that come with them on ebay. the ULN2803 has 8 output pins so can drive two motors from one chip, instead of the 7 pins on the ULN2003.
The buck/boost converter will supply the requested voltage OR current if I remember correctly. :)
Meanwhile in china:
Boss: "Where da fuck is the blue capacitor"
Employe= "On youtube xD"
Boos: "UR FIRED !"
I have one of those buck boosts you opened at the start, and it works really well except when plugging I plug it in, the output spikes quite horribly high before realising it should be off :/
Those little green boxes are perfect for storing low-wattage resistors regardless of the fact that the ones I've found say that they're for SMDs.
I think Dave Jones would say that boost buck converter is a little dodgy.
How rude. That converter with its squealing inductor was only trying to match Jones' screechy voice.
i'd say the DC load is oscillating AND the DC-DC has terrible transient response.
another great postbag!! thanks Julian.
Cool, a free capacitor. Those boxes look real nice, especially lid opening mechanism.
im voting for dac/headphone amplifier diy build series! :D would be superfun!
I wonder if the DC-DC converter could be improved by having an adjustable voltage regulator on the output instead. The voltage regulator would bring it down cleanly to the desired voltage and the boost converter would bring the input voltage up to just above what the regulator needs. That way, maybe, you could get the best of both worlds. Clean output with the efficiency of a switch mode power supply.
Bought the Boost Buck PSU myself a while back, on my unit the inductor noise is only noticable when pushing the output to 34v+
Didn't see many dodgy misaligned components as you do.
No extra capacitor as well :p
i use plastic test tubes for my resistor collection..works great.
I think that it was jumping between cc and cv mode... just up current limit on the psu
Really interesting video! If you ever plan to use the boost/buck converter continuously the "squealing" might pose a rather big problem though, because it means the windings are moving slightly which will slowly rub off the isolating lacquer. In general this sound is a sign of bad design... Just to keep in mind.
Hey it looks like your step up step down module has a UART. Wouldn't it be cool if it had test functionality on that?
+BoltActionPiano I've checked it on other models - it doesn't seem to be active :(
These 28BYJ-48 stepper motors can be hacked to bipolar (they are unipolar) which adds alot of torque to them, I used them with this hack to build a 3d printer, feel free to test the hack out for a video if you want to.
On the Step-Up/Down converter: shouldn't there be a "voltage gap" in the middle, around the voltage of your input? So for example if you're putting in 13.5V (I can't remember the exact number you said), shouldn't it only be able to go down to do, let's say, 0-12.5V and 14.5V-max? Because there's always a minimum difference when it steps up or down? When you were scrolling through the voltages it didn't ever seem to jump, and it seemed to let you set the exact voltage you had coming in. But then maybe if you try to actually use that voltage it will change it?
When the input and output voltages are close together, both the step-up and step-down circuits are active. The voltage between them will be higher.
Nice things. Too bad almost all of them have the "Does not ship to Mexico" in the description. :(
When buying those boxes, make sure that you buy same brand as you have three, WenTai, they works well. There are others that looks exactly same, but are totally rubbish. (I think the one Adafruit also sells are wentai). But, ESD?, nah, only the black ones are antistatic I think.
I bought those component trays some time ago - for my resistors. There were sticky paper tags on some lids. When I tried to wash off the glue residue, I found that the plastic of the lids degrades and will easily shatter after being exposed to isopropyl alcohol. Please can you try this on you batch? Also, the fit of may containers is not the best. Do you share that experience?
I just bought 50 of the green ones, luckily they were all packaged seperately, without any stickers on them, except one. Isopropyl alcohol didn't have any effect on that one. The fit really isn't the best on some of them, but at least the fit is not too loose. Also, the opening mechanism on some of them seems to be stuck, did you experience that too?
maybe i got knock-offs, but they look exactly like the ones here. the clear part of mine gets brittle after contact with alcohol (and showing some fine cracquelure). yes, some mechanisms were stuck. the hinges do break off easily. i have the smaller version (third width) too. both combine well but the fit can be very firm.
Those component boxes look great and a good price - might just order.
I just bought 50 of the green ones to store resistors and a few of the other sizes. They are great.
power the load separatly from a floating supply. add some capacitance at the load dut socket.
Hey julian, you're videos are boss, i was wondering if you fancied doing a themed post bag on wireless arduino interfaces? I'm in the process of building a painfully complex arduino/stepper thing and trying to settle on BT or 433 or other options ? cheers
The input wire connector is installed backwards. LOL!
My guess is the six-pin knob was not a pot but a digital incremental encoder.
What range of current, DC-DC converter supports? I mean the min current, to play with leds for example
Thank you Julian. Great info!
The resistor storage box look much better then the crap i purchased from China. Obviously the unit was quite cheap but its locking mechanism was so flimsy that the doors will open by a modrate shake spilling all the components. Can anyone suggest better options available in 2022 for resistor/chip storage ?
cheap AND you get a free bonus capacitor? man things just keep getting better
You have a fire extinguisher at hand right?
Good video
That dummy load set up may not work due to ground currents.
Do you get many faulty products from Banggood? My first purchase (a LiPo Battery) is faulty, only a couple of quid, but asked for a refund, taken 3 weeks so far. A bit reluctant to buy anything more expensive...like over 3 quid :-)
You aren't using the DC Load correctly. It is a "4-wire unit", and you need to connect the other 2 (voltage) cables to the small white connector in front of the load (amperage) connectors on the right side.
neat, you just love the power stuff :)
It would be cool if they added 3d case maps so we could 3d print a case at home for these electronics :)
It'd be somewhat simple to model one in CAD
If you're still interested in that I could throw a model together for you
Awesome my friend.
Is it harder to find ac to dc converters,I no you seem to use ,a lot of DC to DC converters..
Hey Julian, I just found a power bank, and I wonder if you have heard of it. It is the Luxa2 41600mah power bank and it is "the largest power bank in the world", and I'm curious if the 41,600mah is a complete lie or if it is true. It has good reviews and people say it lasts forever charging their phones but this thing only measures 3.9'' square.
+Keagan Knapp It looks genuine enough, but with all that stored energy it's a shame it only has USB outputs. A multi-voltage output would be useful on that thing.
+Julian Ilett I was thinking the same thing. I'm going to parallel up a couple (if not all 3) of the 2A ports and see if I can run a small boost converter off of it, and while I'm at it replace the blue leds with a few warm white ones if I can get the case open.
+Keagan Knapp I wonder if it's safe to connect the outputs in parallel. Maybe you know it is, or someone else can advise.
+Ray Kent I wish I could tell you I knew, but I do remember using a high powered usb device, what it was exactly I do not recall, but it used 2 male usb cords for power. I will take the power bank apart when I get it to make sure nothing is out the ordinary on the 2A ports.
Quick google search says they use 16 LG cells in there, and another search points to LGs 18650 powerbank-ey type cells to be around 2600mah. So yeah seems legit.
Like Julian said though, shame it's only got USB.
E: Seems like they use these www.batteryspace.com/lg-lithium-nmc-18650-rechargeable-cell-3-7v-2600mah-9-62wh---icr18650b4-un38-3-passed.aspx
is it just me or do those parts look removed from other units?
Unless you use potting compound on the inductors, you'll have to get used to the squealing. ;)
I'll have to check all inductors for freebies from now on lol
Love these vids btw
Great containers ..
Cool stuff.
Why do you get all your stuff from eBay.com and not eBay.co.uk?
+Adam Stewardson Several reasons: much bigger range of stuff on eBay.com - Patreon donations are in dollars - US audience is probably bigger than UK audience.
+Adam Stewardson
Julian has additional reasons, but...
You can get any item from any of the country specific pages, they are (finally) pretty much identical in functionality. The main difference is that sellers can select on which pages to list their items and you won't find items on the country pages even when you know the exact item name, if the seller didn't list it for that country. But you can enter any item id (found on ebay.com for example) into the search bar of a country page and it will get you to the specific item even if the item isn't listed for that country and show the according currency, if you don't want to convert it yourself.
I think ebay.com is the page where all items are always listed. There's really not much point in using your "local" page (in fact many of the chinese seller's shops are totally empty on the ebay.de page for example, while having 1000s of items on ebay.com).
Prices are usually cheaper(some times by a lot) on the US site, than the various country domains. Some items are also not listed on the local sites.
Sorry mate, you need to brush-up on DC theory!
Good thing though, you have curiosity and that will help.
Yay! Free capacitor :D
1:22 free extra capacitor. What a bargain.
That loose Q-apacitor means Q-uality.
Quality control does not exists in most of these places, unfortunately. Often, one needs to resolder/realign components.
Then , there is piss-poor packaging , items arrive damaged or unusable. Great shame though, China is yet to learn importance of product quality.
they thrive off cutting all corners to lower costs, we would not be able to buy half the cheap electronics if they suddenly decided to implement quality control
Though those boxes are nice, they can be overkill.
Eat some tic tac and store resistors in their box...that's how I do it
My dad used to make paper bag using staples for same purpose
Don't know about tour country but a box of tictac costs me 10 inr or 15 cents
+Suraj Grewal
Actually a preety cool idea, I think I have to save my tic tac boxes from now on.
But man, 15 cents?!
where I live it's more like 1 buck 15 ....
if it gets too expensive,then its time to learn origami and make some out of card-paper
+Suraj Grewal
haha, that probably is an even greater idea :)
I don't know if I would like playing around with something that makes weird noises.
I would not point those electrolytics at my face if I was you!
+Chris Ellingson Probably sensible, although I am wearing reading glasses.
+Chris Ellingson I once had a solid capacitor exploded very close to my eye from a cheap DC to DC converter!! It starting making a weird noise so I held it into be face to hear it better, then BANG!!
maybe they are PWMing the mosfet in the load xD
Can't complain about a free capacitor. lol
Julian!! Sorry. Sir Julian Ilett.
I will make sure I don't buy one of those DC Converters lol - not unless I need extra parts and want to practice resoldering - that's just horrible quality even from China.
+Digger D
Quality? China?
+jpalm32 China can do decent quality, but if you will buy the cheapest product available...
Samuel Doye Look at the price - for a dc converter it wasn't that cheap - you can get cheaper ones that actually work ;)
+Digger D Fair enough, I didn't look at the price. I assumed something this questionable would be rather cheap.
+Digger D Can someone start posting video's of item's like this that are better quality and not made in China, but at similar same prices. On UA-cam there's so much hate for cheap non big brand Chinese made stuff, It's time for someone to show us a long welcomed alternative :-)
separated power supplys!!!!
thanks npw my ears hurt
firsted!