@@AndreasSpiess You could also say a few words about "wires" -- people have a lot of trouble with esp32 brownouts that seem to be caused by long thin wires -- either cheap usb cables, or breadboard wires -- coming from a decent battery or usb supply, but the wires can't handle the current.
Andreas, when it comes to USB Power Delivery, consider taking a look at the ZY12PDN. These use a button to select between 5, 9, 12, 15, and 20v. You can hold the button down when plugging it in to select the voltage it powers up at, which is really convenient.
@@AndreasSpiess No, but if you hold down the button when you first plug it in, it will start blinking. Pick the voltage, then long-press. It saves it to internal flash, so the next time it comes in, it has the right voltage. It's not as obvious as it should be.
Thank you Andreas, excellent video. Although it confirmed my assumption that recycling the usb power adapters in the house is the best methhod for powering my simple projects I learned 2 important lessons: 1- I have been wondering for YEARS why anyone would still choose a linear power adapter, when the newer switching models were so much smaller, efficient and cheaper. You answered this very clearly. 2- I also had bought a number of 7805's "just in case" I need them - since they seemed to be so commonly used in many projects - but I also read some people dismissing them as inferior compared to other regulators. Now I know what they are talking about. Finally: Yes please I would be very interested in a similar video about battery powering options.
Dear Andreas I'm happy to see that you are somehow using my parametric box designs to make your boxes I might be wrong though... but if I helped YOU I'm more than happy to help an hero of mine! LOL. Would like to love one of batteries and solar power!
Hello Andreas, sure we are interested in power supply with batteries. As you comment in the video please consider also to investigate how to avoid noises on PIR ans radar sensors with our loved esp modules. Battery powered with mqtt could be a great intrusion alarm system but the false positive now makes it poor realistic with the ESP modules.
Andreas, I agree with the compliments and appreciation expressed below. Also, when you discuss battery power options in a planned video, would you consider adding ideas for monitoring the battery voltage and using LoRa to send periodic measurements to the cloud? I want to show trend graphs and send low batt alerts for remote AREDN radio sites on 12v solar systems. Many thanks!!!
It would be very interesting to investigate rechargeable battery power in cold weather applications - lithium batteries are revolutionary but they can not be charged at temperatures below 0C. Lead based batteries seem to be the only viable alternative as far as I have read.
@@AndreasSpiess There are some solutions to lithium charging but warming the batteries does not lend itself well to small projects. I have heard promising things about some LiFe cells that claim to be rechargeable down to -20C but they do not seem to be commonly available.
Just one questio: Do all AC-DC adapter (with USB output) have a regulated and stable output voltage? If it's not, how can i ensure if i need some regolation after my adapter? In my case i need to power and arduino with a couple relay and a SIM module (which require up to 2A during network registration). Thaks a lot!
Voltage is constant in Swiss only....here it drops normally fron 220V to 170V or less expecially during summer when all air conditioners are on....besides it disappears 4 or 5 times for week..... this is something to take in consideration in proyects. 73 de ZP4KFX
@@AndreasSpiess right ! infact my old home made linear is almost useless here...not only the AT is low, but also the filaments remain cold.....now I own a SPE Expert 1.3K-FA which works fine even at 110V.....73
My RPi-4 didn't like running on a regular USB power brick, $ vcgencmd get_throttled returned that it throttled itself on a vanilla setup. Doesn't happen on a USB power supply that is marketed specifically for the RPi-4. I read that normal USB power bricks can't supply stable 5V voltage.
Andreas, I can't even begin to describe to you how indispensable you are to the maker community! Thank you for everything you do! I would love to see your explanation of battery powering devices. Keep up the great videos, as always!
Question: if I want to connect my phone to a buck converter ran by a battery, do I need to worry about the amp capacity of the battery frying my phone? Does a phone limit amperage used?
I love the "swiss guy" method of checking how hot the regulator gets , also as Cristi Istrate battery and solar charging for a remote weather station would be great to see, again thanks for the great info :)
This method is actually used planet-wide. It works as long the reaction time by the tester is quicker than a rapid temperature increase. Putting some water on a fingertip will give you little bit more time to react.
Yes battery vid probably now the most useful as most will use this type to power projects. Alsoand for an alternative update the UPS video and more boards about
Useful thanks and try not buy cheap no brand chargers I have seen one (a Samsung fake)and when I asked the amperage the guy said 270wats (?) and the brand name is “Orignal”. You might buy it and just forget it over time it dies and causes trouble. For small converters I keep some small heatsinks around.
If you do not have a basic knowledge about any products, you have to trust the supplier. Here is a good page: lygte-info.dk/info/ChargerIndex%20UK.html concerning power supplies
Sorry but I had to stop at 2:51 and go to video 244 where you gave me a revelation and now I am trying to make my powerbank output 12v!!! I will carry on with this video later :D
@Andreas Spiess Thank you I think the swiss guy method to check the heat sink temperature damage your finger ;-) To take an external adapter is for most hobbyist the best solution. No high voltage inside the system. Maybe also less EMC problems. To take one of the silver chassis power supplies a hint for earth connection seems recommended. Also if people take a more power full power supply for low power systems as ESP or Raspberry Pi an additional fuse on 5V side is also recommended. Otherwise a short circuit on DC could damage your application. A fire also could damage your room or house. Sometimes I saw on youtube that people take an adapter or silver chassis power supply --> psu inside a box without ventilation holes. Then you have to measure inside temperature and check datasheet of psu to find out at derating curve which power the psu will deliver at 50 or 60 degree. Attention! The power supply will not derate automatically. Good ventilation with fan or holes is also suggestet.
I always have to concentrate a lot to get videos short. So I cannot cover all aspects. Concerning fuses: There you can see the character of a person. I would check that aspect before marriage. My character tends to "fewer fuses" ;-)
Whatever valuable project you have, never buy chinese products from ebay/aliexpress. Always buy quality branded stuff from certified sellers like Farnell, RS, Digikey, TME, Pimoroni, Adafruit etc. Another thing make sure that if you use some DC-DC converter it is able to deal with reverse voltage input without outputting full 12-24V input voltage to your 5V/3V3 device. I had used one of these cheap ass buck converters for $1 to power RaspberryPi Zero W from 24V and accidentally applied voltage other way around, smoke went right out. But if you need high amperage PSU like 50A+ you can use PSUs from retired servers, those were maybe used for 5 years already but they were designed to work 10 years so you still have a lot of use from them most of the time, and they're dirt cheap, most of the time you just need to short pin or two to activate them. One of the popular one is DPS600PB, it is 12V 47A, it can even be adjusted up to 15V, or connected either in parallel or in series, best thin it can be bought for as low as $10.
The tip for using server PS is a good one if oyu need around 12 volts and lots of ampere. Most of my products are "made in china" (as well as most products you get from Digikey or other distributors). I have no problem with that.
@@AndreasSpiess Made in china is not the problem, it's low quality or fakes that you usually end up with buy choosing ebay/aliexpress/wish. It's about trusted source. Some of these server PSU come with 50V outputs as well for example 226519-001 which is 3kW for $50, asbolute steal.
Using your calibrated finger as a thermal sensor brings back memories from my old power supply design days. We would touch a hot device and if you could say 'supercalifragilisticexpialidocious' without removing your hand its ok. An approach that proved surprisingly accurate when confirmed with more sophisticated thermal instrumentation.
Does a buck converter count as a switching regulator? I use them all to time to divide a mains transformer into various voltages to run my project on one plug. They seem very efficient and are cheap off ebay.
Yes. I use those modules all the time and I prefer them over 78xx regulators in almost any case. (in the past I usually used several 78xx regulators in a project but these new buck converter modules are really nice to use, no cooling required)
@@Rob2 Thanks. Some of the really cheap ones tend to have problems though where the trimpot doesn't exceed a certain range after a couple of uses, but a replacement of the same spec bought somewhere else works. Ah the minefield of Chinese manufacturing.
Can I power (only) my ESP32 with a 5v 1a (5w) usb power supply? Or do I need theese other strange components? So the problem I am facing here is that I would like to upload code via micro USB and the Arduino IDE to my ESP32 and then be able to run it and turn off my pc. So I would have to upload the code, somehow run the code and change the micro USB plug from the one that runs to the Pc to the one that is connected to the power supply (5v 1a 5w) at the same time, so it is running with the power of the power supply. I don’t need the searial monitor for this project. Thanks
If you know of a good buck-boost chip that is easy to calculate and design for, I would be interested. I have my references saved for the MC34063 and UC3842. I've used the MC34063 several times. I've modified circuits with the UC3842, but still haven't built anything from scratch. The inability to measure inductors accurately makes me hesitate to build something over 10-20 watts from scratch. I would rather use a working mains power brick design and modify it to suit my needs. I would probably need something like a component calculator for a buck-boost topology. This is how I got started with the MC34063 and UC3842. The key for me was a calculator that allowed me to change values on the fly. For instance, I can input the frequency, voltage, current, and acceptable ripple noise, and things like the inductance and component values are given. Lots of tools can do this, but the most effective ones can reverse the calculation. Meaning, I can modify the initial results to change the inductance value and see the way it influences voltage/current/noise. This allows me to design something based on what I already have laying around. Ultimately, I need either a thorough breakdown of the topology and application, or I need a way to plug my values into the simplest possible equations to get started. I have salvaged a couple of buck-boost circuits from old wireless computer mice, but the datasheets for the chips I've seen are not very good, usually not in English either. I don't have a go-to example I am confident I can replicate. Thanks for the upload. -Jake
I once started to watch some videos about the construction of power supplies and decided not to start with this "science". So I do not know particular chips. I buy them on boards. BTW you get reasonably priced LCR meters (I have a DE-5000) and even the cheap transistor testers were quite accurate when I did a few comparisons.
I get the general idea of the "Swiss Guy" method, but exactly what is the range of good versus bad in this test? And, since you are using a gloved hand in the video, how does that change the perceived result? We used to use a USA Underwriter's Lab (UL) standard for the maximum allowable temperature for the cases of our office equipment. The number is 137 degrees F (58 C). It is, according to UL, the maximum temperature on a surface that a human can touch for an extended period of time without having to say "ouch". Is that what you have in mind? And how do you deal with it when you are wearing gloves? ----Maybe I am just nit-picking?
I assume our sensors are similar here, just calibrated in degrees centigrade ;-) 60 degrees centigrade is usually not bad because most parts are rated higher. So you the risk is mitigated.
I want to use 5 V from PC usb for my RF-converter for rtl-sdr. What actions should I take against noise in the power line? Would simple LC-filter works OK? Or maybe I don't need anything to do?
Thanks a million. I am still playing with my web radio. I recently rebuilt it, trying to use my 12 volt cell built from an old Apple Laptop battery. What used to be a very clear, wonderful sounding radio now has a horrid hum playing behind the music or talk. I hope that when you get to the battery part of this series the answer to my problem will come up. Oh my mind needs the distraction now, you see we met with the doctor Friday and were told that my good wife of 51 years has a rare version of cancer in her stomach and liver. They can't tell yet, how aggressive it is because it has been known to be nearly benine to very aggressive. Right now they put her in the mid scale. She is home from hospital right now on very strong pain meds, and going through hell. It breaks my heart to see her like this but I guess it's all part of getting old. We should be hearing from the specialist that has been assigned her case next week so we know what treatments are available, and, well, how aggressive we can expect it to be.
I'm having a power supply problem that is driving me crazy, because it seems so simple: I have an ESP8266 with BME280 temperature/humidity/pressure sensor, a radar motion detector, and an LDR with some resistors to measure light. I have a 1,000uF capacitor on the 5V pin. It works fine when powered from my laptop USB. But when I put it on a USB power supply, the BME280 sensor returns bad values (temperature -145.10, pressure 1238.77, humidity 0), but everything else works. I started with my usual very cheap 1A USB power supplies, then tried cheap 2A supplies, then an official Raspberry Pi 2.5A supply, then a 3A powered USB hub, with the same result. It has been working fine from my laptop for a week now, but that means I have to leave my laptop on and I can't take it anywhere! Is there a design difference between a laptop USB and a USB power supply? Am I overlooking something obvious? I plan to put some of these outside, using solar powered powerbanks, so I hope you will cover those next...
As always many thanks. My current project is an environmental sensor using the LoRa technology (TTGO LORA32, BME280 plus an analog temp sensor, LiPO 1S battery, maybe solar charger). For use in lobster and mussel farming. Working on the electrical requirements now (i.e. voltage supervisor?, regulator needed?, anything else?). Hoping to get 2 years maintenance free. Looking forward to your next video.
I have a project in which I have an Arduino Nano which needs to power a NEMA 17 stepper motor via a A4988 driver. I have a 12V/2A DC adapter. The question is... Can I connect this supply both to the Vin pin on the arduino AND the Vmotor pin on the A4988 and power both of them at the same time (without using an additional 5V power supply for the arduino)? Note that I would like to use the Vin pin because it accepts 12V as well, so I don't even need a buck converter... Thanks!
I would not power the Arduino with 12 volts. The AMS1117 voltage regulator probably gets quite hot. But maybe you try and put your finger on the voltage regulator.
Funny that I have been info seekning voltage regulators for MCU:s all day, then you release this video today. Great content and clear explainations as always! I was almost ready to order some LM2596 based boards, but a commenter mentioned that ripple could be as high as 300mV peak-to-peak on those. Is that tolerable for e.g. an ESP32? Can we filter it with a capacitor? What are some good buck converters with low noise?
I fully agree with Daily Cake Slice. Among the Development Board drawings I sent you, there is a new idea for battery power or main power. For batteries you can use a good size 6V, charged by solar and then go to MCP 73123 charger to a 3.3V Lifepo4 Battery to run the ESP WiFi. It hasn't been tested.
There are only a few chargers which also handle LiFePo. If I remember right, the TP5000 uses the MCP 73123. And you are right, LiFePos are a good choice for ESP projects...
Laptop power supplies are great if you need a bit more power. They are mostly well-built, safe, compact, widely available and their typical 19V output is easy to buck down at the point of load as many switchers accept up to 24V. For OCD sufferers who don't want to cut off the nicely molded original plug it can be a challenge to find the matching input jack :-)
Thank you for all your work. Only a small problem in this one : the arrow showing voltage are strangely oriented (input, output, drop voltage, ...) we generaly use the arrow head to point the more positive wire : en.wikipedia.org/wiki/Passive_sign_convention . - comparing riple and other EMC parameters between switching and linear could give more acurate choice parameter - batery properties (Nixx or Lixx or Pbxx) and charging/discharging is well documented (in french) on ni-cd.net
I'd love to work on creating reference schematics with simulation to help people find the right Battery Supply for their project in Flux (www.flux.ai). When do you think a battery supply video will come out?
A current project I'm working on requires 5 V to power the MCU and various software controlled outputs via USB as well as switching mains on and off via an isolated relay board. I may also need to add some fans for air circulation, also software controlled, which will need a 12 V supply. This video couldn't have come at a better time. Current plan is to hack a socket mount power adapter with built in USB outputs, add a fused power socket with switch, and mount a 240 V socket with switch on the back so mains devices don't need to be butchered to make them compatible. Will be able to add a ground connection too, something that is frequently absent in cheap products even if it would be desirable to have such a thing installed. And yes, a battery version would be grand too! Many thanks.
I am very elementary to this power supply stuff and don't know a thing really. I know I need to watch what I am up to with my 3.3v and 5v sensors with my Arduino's and such - barely. But... ...a coverage on batteries would be good because with people looking for green/renewable energy resources, rechargeable battery power supplies might be of interest to some. Such very thorough work as always Andreas - thank you.
Andreas your brain is like a black hole soaking up all knowledge then firing it out like a beam of inspiration across the network... thank you for sharing
yes yes yes, please do a video about battery powering devices. I always have difficulties to find good booster, and if I should try to get an all-in-one board (charger & battery protection &booster), or if it is better to have everything separated. Also interesting would be a discussion in very low power devices, i.e. I have an arduino and RFM22 sending data every 5 minutes working on a single AA battery for 4 to 5 years!
I'd be interested to see if the linear regulator is actually (electrically) quieter than a buck converter. The linear will propagate the ESP32's noise over the 12V line in addition to the keyboard power line. A switcher will usually be filtered a bit more, and might just reduce the ESP's noise more than a linear.
I actually expected something about power supply shown on top left corner at 0:16, but it is none the less very informative! What about powering multiple loads from single power source? I'm working on replacing dozen of power supplies 12v in network rack with single power supply which I also can keep multiple spares
Again another great video :) I’m building a large 16^3 led cube with pl9823 leds. If you calculate the power i need -> 60mA x 4096 x 5v = 1200 watt... So i bought 4 60A, 5V powersupplies, thick wire for 15A, per 256 leds. The proof of concept works. But i also want a kind of standby mode. Leds that are powered, but off, use arround 1mA... Thats 20 watt when off.... So how i was thinking using mosfets to turn all power off (need to switch the 5v, not ground, according to adafruit guide) but with 240A total those mosfet resistances RDSon will also have a huge impact. There is some overlap with battery powered project here (minimize quiescence current). Always something to learn... I’ll think i’ll go read in my electrical engineering book and figure out what to do with those huge current, but watching your youtube video’s is so much more fun ;-)
This should not be too complex. You just have to find a stable and capable 5V supply according to the rules shown here. Probably a switcher in this case.
I would have loved to get some information on power loss when project is in idle for always connected projects. Is there something which should be observed for such an case. For example a µC controlling multiple light outputs and most of the time standing by until lights get turned on. What's efficiency on such low power or is that something which does not matter at all?
It depends on your view if it matters. If you build one project, the grey energy inside the project is factors bigger than the standby current. And if you drive to the next supermarket you waste more energy than your project for the next 5 years... It might be different if you sell a million devices of your project.
I am trying to make a temperature sensor but it seems to work fine with a lithium ion battery but I want to use it with mains power supply and the temperature keeps jumping while I use a 2AMP power brick.any solutions???😞
Any chance you could do an episode on spread spectrum switching converters? They vary the frequency randomly around the center frequency. This lowers peak power at the center frequency and makes it easier to filter out switching noise. I've been keeping my eye out for such a project, but haven't seen anyone do a video on one yet.
An IR temperature sensor will give more accurate results and kill off fewer of your subscribers. Seriously, most people are much less detail oriented than you are...
I keep reading on the rasberry pi forums that you should use proper power supplies rather than mobile phone chargers. Supposedly mobile phone chargers not designed to provide constant power over time. Sound bogus to me and people trying to justify the official pi psu.
All voltage regulators now have thermal protection, you do no need sophisticated Swiss method. If your device turns off for several seconds and then turns on again - your voltage regulator needs a heatsink.
Thanks for your video, Andreas! Do you have some tests of the USB-C PD power outlets? Thinking of using a big USB-C power bank to drive my High-End DAC. But what is the quality of the USB-C outputs of a power bank?
Switching regulators and high end audio is probably not a marriage made in heaven... But no, so far I did not do any tests other than using one for my portable radio station. Works quite well at 15 volts and so far I did not have issues with RFI. But I use much higher frequencies...
@@AndreasSpiess thanks for your response. You are right regarding switch mode psu. But if running on battery from a power bank? I see some high end equipment doing that. I can't find any measurements on the quality from the power bank outlets. Br 🙂
Grüezi Andreas, many thanks (again) for this video - while I “somehow” knew how to power my projects I do now have a very structured approach to it. I’d love to see the battery video - greetings ausm großen Kanton ;-)
Lol, the swiss guy method was the 60 degrees rule during my electronics class. If you could put your finger on for 5 seconds the temperature is less than 60 degrees.
Sunday morning: sun, croissant, coffee & Andreas answering my project questions. A good way to start the day. Thanks andreas ! Ps. From across the room my gf says you sound way younger.
Hi, I ordered a switching powersupply kinda similar to the powersupply you have shown in the vid. It has 12V 5A specs. I wanted to power arduino nano using it. Of course, i would lower it to 5V using buck converter, but i'm concerned with the "5A" specs on the psu. Would it burn my arduino? P.S. The reason i used this because I'm also about to use motor that needs 12V instead of just using USB to power arduino
Hi Andreas, I have a P-Touch H107. Since I do not like batteries in things that I use on my desk, I have drilled a hole and connected a wall adaptor plug to the red and black cables that come from the battery compartment. I have also soldered a schottky between the red cable and the plug. The printer goes with 6xAAA batteries so I have plugged a 9v transformer and nothing happened. Whith some batteries I had around it worked and I could read 7.5v at the input. So I tried a 7.5v transformer, and a 12v and a 5v. Nothing, and the meter reads weird values at the board (like 11-15v). But the curious fact is, that with a power board (from ebay), set to 7.5v, connected to the plug, it works perfectly!! What could be going on?
Andreas Spiess: I have tried with a variable (“universal”) adaptor ad it works fine too. In the end, I guess that I must have a significant number of broken transformers in that box 🤣🤣
Useful, battery supplies next please 👍
Noted!
@@AndreasSpiess You could also say a few words about "wires" -- people have a lot of trouble with esp32 brownouts that seem to be caused by long thin wires -- either cheap usb cables, or breadboard wires -- coming from a decent battery or usb supply, but the wires can't handle the current.
Andreas, when it comes to USB Power Delivery, consider taking a look at the ZY12PDN. These use a button to select between 5, 9, 12, 15, and 20v. You can hold the button down when plugging it in to select the voltage it powers up at, which is really convenient.
I have soch a PCB. Would you like to push buttons every time you start your project?
@@AndreasSpiess No, but if you hold down the button when you first plug it in, it will start blinking. Pick the voltage, then long-press. It saves it to internal flash, so the next time it comes in, it has the right voltage.
It's not as obvious as it should be.
Thank you for the tip!
Thank you Andreas, excellent video. Although it confirmed my assumption that recycling the usb power adapters in the house is the best methhod for powering my simple projects I learned 2 important lessons: 1- I have been wondering for YEARS why anyone would still choose a linear power adapter, when the newer switching models were so much smaller, efficient and cheaper. You answered this very clearly. 2- I also had bought a number of 7805's "just in case" I need them - since they seemed to be so commonly used in many projects - but I also read some people dismissing them as inferior compared to other regulators. Now I know what they are talking about. Finally: Yes please I would be very interested in a similar video about battery powering options.
The 78XX are nearly as old as I am. So for sure you get better ones these day. But they work for mains powered projects and are cheap...
Dear Andreas I'm happy to see that you are somehow using my parametric box designs to make your boxes I might be wrong though... but if I helped YOU I'm more than happy to help an hero of mine! LOL. Would like to love one of batteries and solar power!
I use my own design in Fusion360 (I showed it once in a video). I like this aproache because I alsways need some special cases...
Hello Andreas, sure we are interested in power supply with batteries.
As you comment in the video please consider also to investigate how to avoid noises on PIR ans radar sensors with our loved esp modules. Battery powered with mqtt could be a great intrusion alarm system but the false positive now makes it poor realistic with the ESP modules.
I made some remarks about the topic in one of my last videos. I think it was a mailbag.
Great video. Please kindly make one about Battery Supplies for makers.
Noted
Andreas, I agree with the compliments and appreciation expressed below. Also, when you discuss battery power options in a planned video, would you consider adding ideas for monitoring the battery voltage and using LoRa to send periodic measurements to the cloud? I want to show trend graphs and send low batt alerts for remote AREDN radio sites on 12v solar systems. Many thanks!!!
Usually you can build your particular project with parts of my videos...
Thank you for this. And yes please do one for battery powered projects.
Noted!
It would be very interesting to investigate rechargeable battery power in cold weather applications - lithium batteries are revolutionary but they can not be charged at temperatures below 0C. Lead based batteries seem to be the only viable alternative as far as I have read.
We had big discussions about that in another video. Maybe you watch this video: ua-cam.com/video/y5STYw0BnBg/v-deo.html
@@AndreasSpiess There are some solutions to lithium charging but warming the batteries does not lend itself well to small projects. I have heard promising things about some LiFe cells that claim to be rechargeable down to -20C but they do not seem to be commonly available.
This is the video i was looking for! Thanks!
Just one questio: Do all AC-DC adapter (with USB output) have a regulated and stable output voltage? If it's not, how can i ensure if i need some regolation after my adapter? In my case i need to power and arduino with a couple relay and a SIM module (which require up to 2A during network registration). Thaks a lot!
Just consult the datasheet (or the marking on the device) and you should see if they are regulated. USB connectors always have regulated voltages.
@@AndreasSpiess thanks a lot!
Voltage is constant in Swiss only....here it drops normally fron 220V to 170V or less expecially during summer when all air conditioners are on....besides it disappears 4 or 5 times for week..... this is something to take in consideration in proyects. 73 de ZP4KFX
That is not good. Probably not for our small projects, but for sure for your Linear Amplifier...
@@AndreasSpiess right ! infact my old home made linear is almost useless here...not only the AT is low, but also the filaments remain cold.....now I own a SPE Expert 1.3K-FA which works fine even at 110V.....73
long awaited. thank you
You are welcome!
My RPi-4 didn't like running on a regular USB power brick, $ vcgencmd get_throttled returned that it throttled itself on a vanilla setup. Doesn't happen on a USB power supply that is marketed specifically for the RPi-4. I read that normal USB power bricks can't supply stable 5V voltage.
As said, many new PS can do it without problems. And tthe USB-C cables seem to be good. Just do not use a too long one....
@@AndreasSpiess Oh, thanks for that! So cable length plays into stable voltage?
Maybe you watch my video about serial cables
Andreas, I can't even begin to describe to you how indispensable you are to the maker community! Thank you for everything you do!
I would love to see your explanation of battery powering devices. Keep up the great videos, as always!
Well put on both counts, I fully agree.
Thank you for your very nice words!
Question: if I want to connect my phone to a buck converter ran by a battery, do I need to worry about the amp capacity of the battery frying my phone?
Does a phone limit amperage used?
Nice overview ... and yes do it for battery solutions too (please) - 73 from Berlin
Thank you! Maybe I should include all videos already done by me for batteries...
Battery powered and solar charging, for a external weather station will be nice to discuss.
Thank you for your feedback!
Really, there were a couple of videos from Andreas concerning this specific subject, the series was abruptly interrupted due to lack of sun
I agree!
@@AndreasSpiess I really want to know about this!!!
I agree!
I love the "swiss guy" method of checking how hot the regulator gets , also as Cristi Istrate battery and solar charging for a remote weather station would be great to see, again thanks for the great info :)
This method is actually used planet-wide. It works as long the reaction time by the tester is quicker than a rapid temperature increase. Putting some water on a fingertip will give you little bit more time to react.
Noted!
Andreas, A useful follow-up video should be on smoothing, de-coupling, ripple, noise , etc. Are there some "Swiss Guy" solutions here too?
This is a rather special area, maybe not too interesting for many subscribers :-(
whitefields5595 EEVBlog has good videos for that.
Andreas Spiess I would still love to see your video on it. Your videos are always very straightforward without much laber rhabarber.
@@AndreasSpiess Haha, you are right. Also EMC is a big problem for hobbyist to solve. I will say impossible!
I'm definitely interested in those topics, especially if illuminated the "Swiss Guy" way!
Yes battery vid probably now the most useful as most will use this type to power projects. Alsoand for an alternative update the UPS video and more boards about
I have some boards in the mail. Since quite a long time :-(
Powercap Supercaps (12×500F )×3 Accu Battery 2,7V Farad ➡️ ua-cam.com/video/ihSc7Bj_oQk/v-deo.html
Solar PV Limiter Inverter
8 years in switzerland and is the first time I heard of such a swiss precision thermometer!
only the watches are more precies ;-)
You see, it is worthwhile to sit in the first row ;-)
Yes. Please do a battery video. I make esp32 /arduino robots and need to supply 3.3 for the mpu and 6-12 volts for the motors.
Thank you for your feedback!
Thanks Andreas. I'm looking for the next episode regarding battery supplies.
Thank you for your feedback!
Useful thanks and try not buy cheap no brand chargers I have seen one (a Samsung fake)and when I asked the amperage the guy said 270wats (?) and the brand name is “Orignal”. You might buy it and just forget it over time it dies and causes trouble. For small converters I keep some small heatsinks around.
If you do not have a basic knowledge about any products, you have to trust the supplier. Here is a good page: lygte-info.dk/info/ChargerIndex%20UK.html concerning power supplies
Sorry but I had to stop at 2:51 and go to video 244 where you gave me a revelation and now I am trying to make my powerbank output 12v!!! I will carry on with this video later :D
Take your time!
@Andreas Spiess
Thank you
I think the swiss guy method to check the heat sink temperature damage your finger ;-)
To take an external adapter is for most hobbyist the best solution. No high voltage inside the system. Maybe also less EMC problems.
To take one of the silver chassis power supplies a hint for earth connection seems recommended.
Also if people take a more power full power supply for low power systems as ESP or Raspberry Pi an additional fuse on 5V side is also recommended.
Otherwise a short circuit on DC could damage your application. A fire also could damage your room or house.
Sometimes I saw on youtube that people take an adapter or silver chassis power supply --> psu inside a box without ventilation holes. Then you have to measure inside temperature and check datasheet of psu to find out at derating curve which power the psu will deliver at 50 or 60 degree. Attention! The power supply will not derate automatically.
Good ventilation with fan or holes is also suggestet.
I think my grandmother used a similar method for checking the flat iron was up to temperature :)
I always have to concentrate a lot to get videos short. So I cannot cover all aspects. Concerning fuses: There you can see the character of a person. I would check that aspect before marriage. My character tends to "fewer fuses" ;-)
As a noob into ESP32 projects I approve this video! Thank you very much for making these!
Glad it was helpful!
I would enjoy a video on battery supply. ...and one on solar charged battery supply. =)
Thank you for your feedback!
Whatever valuable project you have, never buy chinese products from ebay/aliexpress.
Always buy quality branded stuff from certified sellers like Farnell, RS, Digikey, TME, Pimoroni, Adafruit etc.
Another thing make sure that if you use some DC-DC converter it is able to deal with reverse voltage input without outputting full 12-24V input voltage to your 5V/3V3 device.
I had used one of these cheap ass buck converters for $1 to power RaspberryPi Zero W from 24V and accidentally applied voltage other way around, smoke went right out.
But if you need high amperage PSU like 50A+ you can use PSUs from retired servers, those were maybe used for 5 years already but they were designed to work 10 years so you still have a lot of use from them most of the time, and they're dirt cheap, most of the time you just need to short pin or two to activate them.
One of the popular one is DPS600PB, it is 12V 47A, it can even be adjusted up to 15V, or connected either in parallel or in series, best thin it can be bought for as low as $10.
The tip for using server PS is a good one if oyu need around 12 volts and lots of ampere.
Most of my products are "made in china" (as well as most products you get from Digikey or other distributors). I have no problem with that.
@@AndreasSpiess Made in china is not the problem, it's low quality or fakes that you usually end up with buy choosing ebay/aliexpress/wish.
It's about trusted source.
Some of these server PSU come with 50V outputs as well for example 226519-001 which is 3kW for $50, asbolute steal.
13:42 FULL BRIDGE RECTIFIER
are you referring to the electro boom? :)
He did not invent it, he just made a joke of it ;-)
Thankx. Very useful info. Yes please, do a video on battery powered devices.
Thank you for your feedback!
Please make a video how to provide a solar/ battery powered power supply for outdoor projects.
Thank you for your feedback!
Thanks Andreas, yes, battery supplies next....
Noted!
Yes, please. A battery’s focused one would be much appreciated.
Cheers!
Thank you for your feedback!
"Battery powered devices video" - Yes, please!
Noted!
Helpful video 👍 I liked it
Thanks for liking
Thank you, very useful and interesting. Also, yes please for the battery version. I would also like to see solar + battery. Thank you
Noted!
Battery powered.
And explain buck boost converter
Noted!
Using your calibrated finger as a thermal sensor brings back memories from my old power supply design days. We would touch a hot device and if you could say 'supercalifragilisticexpialidocious' without removing your hand its ok. An approach that proved surprisingly accurate when confirmed with more sophisticated thermal instrumentation.
Humans have excellent sensors, I think. And many survived over the centuries without sophisticated instruments...
Does a buck converter count as a switching regulator? I use them all to time to divide a mains transformer into various voltages to run my project on one plug. They seem very efficient and are cheap off ebay.
Yes. I use those modules all the time and I prefer them over 78xx regulators in almost any case.
(in the past I usually used several 78xx regulators in a project but these new buck converter modules are really nice to use, no cooling required)
Buck and boost converters are both switching.
@@Rob2 Thanks. Some of the really cheap ones tend to have problems though where the trimpot doesn't exceed a certain range after a couple of uses, but a replacement of the same spec bought somewhere else works. Ah the minefield of Chinese manufacturing.
@@AndreasSpiess Thanks
Can I power (only) my ESP32 with a 5v 1a (5w) usb power supply? Or do I need theese other strange components?
So the problem I am facing here is that I would like to upload code via micro USB and the Arduino IDE to my ESP32 and then be able to run it and turn off my pc. So I would have to upload the code, somehow run the code and change the micro USB plug from the one that runs to the Pc to the one that is connected to the power supply (5v 1a 5w) at the same time, so it is running with the power of the power supply. I don’t need the searial monitor for this project. Thanks
If you know of a good buck-boost chip that is easy to calculate and design for, I would be interested.
I have my references saved for the MC34063 and UC3842. I've used the MC34063 several times. I've modified circuits with the UC3842, but still haven't built anything from scratch. The inability to measure inductors accurately makes me hesitate to build something over 10-20 watts from scratch. I would rather use a working mains power brick design and modify it to suit my needs.
I would probably need something like a component calculator for a buck-boost topology. This is how I got started with the MC34063 and UC3842. The key for me was a calculator that allowed me to change values on the fly. For instance, I can input the frequency, voltage, current, and acceptable ripple noise, and things like the inductance and component values are given. Lots of tools can do this, but the most effective ones can reverse the calculation. Meaning, I can modify the initial results to change the inductance value and see the way it influences voltage/current/noise. This allows me to design something based on what I already have laying around.
Ultimately, I need either a thorough breakdown of the topology and application, or I need a way to plug my values into the simplest possible equations to get started. I have salvaged a couple of buck-boost circuits from old wireless computer mice, but the datasheets for the chips I've seen are not very good, usually not in English either. I don't have a go-to example I am confident I can replicate.
Thanks for the upload.
-Jake
I once started to watch some videos about the construction of power supplies and decided not to start with this "science". So I do not know particular chips. I buy them on boards. BTW you get reasonably priced LCR meters (I have a DE-5000) and even the cheap transistor testers were quite accurate when I did a few comparisons.
I get the general idea of the "Swiss Guy" method, but exactly what is the range of good versus bad in this test? And, since you are using a gloved hand in the video, how does that change the perceived result? We used to use a USA Underwriter's Lab (UL) standard for the maximum allowable temperature for the cases of our office equipment. The number is 137 degrees F (58 C). It is, according to UL, the maximum temperature on a surface that a human can touch for an extended period of time without having to say "ouch". Is that what you have in mind? And how do you deal with it when you are wearing gloves? ----Maybe I am just nit-picking?
I assume our sensors are similar here, just calibrated in degrees centigrade ;-) 60 degrees centigrade is usually not bad because most parts are rated higher. So you the risk is mitigated.
+1 for battery powered supplies, consider to include pmic's
Thank you for your feedback!
Would like to see a video on battery supply options. That's knowledge I am seriously lacking.
Noted!
Excellent! Another one for batteries please...
Noted!
I want to use 5 V from PC usb for my RF-converter for rtl-sdr. What actions should I take against noise in the power line? Would simple LC-filter works OK? Or maybe I don't need anything to do?
I think most people plug the SDR dongles in their USB connectors. These dongles are not very sensitive anyway.
Thanks a million. I am still playing with my web radio. I recently rebuilt it, trying to use my 12 volt cell built from an old Apple Laptop battery. What used to be a very clear, wonderful sounding radio now has a horrid hum playing behind the music or talk. I hope that when you get to the battery part of this series the answer to my problem will come up. Oh my mind needs the distraction now, you see we met with the doctor Friday and were told that my good wife of 51 years has a rare version of cancer in her stomach and liver. They can't tell yet, how aggressive it is because it has been known to be nearly benine to very aggressive. Right now they put her in the mid scale. She is home from hospital right now on very strong pain meds, and going through hell. It breaks my heart to see her like this but I guess it's all part of getting old. We should be hearing from the specialist that has been assigned her case next week so we know what treatments are available, and, well, how aggressive we can expect it to be.
I wish you a lot of luck. My wife was also extremely ill and now she is well again. I hope the same for your wife!
very handy summary. thanks! and please prepare the battery related one:)
Will do!
I'm having a power supply problem that is driving me crazy, because it seems so simple: I have an ESP8266 with BME280 temperature/humidity/pressure sensor, a radar motion detector, and an LDR with some resistors to measure light. I have a 1,000uF capacitor on the 5V pin. It works fine when powered from my laptop USB. But when I put it on a USB power supply, the BME280 sensor returns bad values (temperature -145.10, pressure 1238.77, humidity 0), but everything else works. I started with my usual very cheap 1A USB power supplies, then tried cheap 2A supplies, then an official Raspberry Pi 2.5A supply, then a 3A powered USB hub, with the same result. It has been working fine from my laptop for a week now, but that means I have to leave my laptop on and I can't take it anywhere! Is there a design difference between a laptop USB and a USB power supply? Am I overlooking something obvious?
I plan to put some of these outside, using solar powered powerbanks, so I hope you will cover those next...
These problems are not easy to hunt down. With a battery it should be better.
As always many thanks. My current project is an environmental sensor using the LoRa technology (TTGO LORA32, BME280 plus an analog temp sensor, LiPO 1S battery, maybe solar charger). For use in lobster and mussel farming. Working on the electrical requirements now (i.e. voltage supervisor?, regulator needed?, anything else?). Hoping to get 2 years maintenance free. Looking forward to your next video.
Always good if projects create a real value!
I have a project in which I have an Arduino Nano which needs to power a NEMA 17 stepper motor via a A4988 driver. I have a 12V/2A DC adapter. The question is... Can I connect this supply both to the Vin pin on the arduino AND the Vmotor pin on the A4988 and power both of them at the same time (without using an additional 5V power supply for the arduino)? Note that I would like to use the Vin pin because it accepts 12V as well, so I don't even need a buck converter... Thanks!
I would not power the Arduino with 12 volts. The AMS1117 voltage regulator probably gets quite hot. But maybe you try and put your finger on the voltage regulator.
Spring is shining outside, robins (or rotkerlchen) sing looking for adventure, the projects migrate outside to sun. Solar!
Noted!
Funny that I have been info seekning voltage regulators for MCU:s all day, then you release this video today. Great content and clear explainations as always!
I was almost ready to order some LM2596 based boards, but a commenter mentioned that ripple could be as high as 300mV peak-to-peak on those. Is that tolerable for e.g. an ESP32? Can we filter it with a capacitor? What are some good buck converters with low noise?
These are quite old boards. Maybe you decide on one I showed in the video...
I fully agree with Daily Cake Slice. Among the Development Board drawings I sent you, there is a new idea for battery power or main power. For batteries you can use a good size 6V, charged by solar and then go to MCP 73123 charger to a 3.3V Lifepo4 Battery to run the ESP WiFi. It hasn't been tested.
There are only a few chargers which also handle LiFePo. If I remember right, the TP5000 uses the MCP 73123. And you are right, LiFePos are a good choice for ESP projects...
Laptop power supplies are great if you need a bit more power. They are mostly well-built, safe, compact, widely available and their typical 19V output is easy to buck down at the point of load as many switchers accept up to 24V.
For OCD sufferers who don't want to cut off the nicely molded original plug it can be a challenge to find the matching input jack :-)
You are right. I also use one to power a small bench power supply. They are also quite strong...
Thank you for all your work. Only a small problem in this one : the arrow showing voltage are strangely oriented (input, output, drop voltage, ...) we generaly use the arrow head to point the more positive wire : en.wikipedia.org/wiki/Passive_sign_convention .
- comparing riple and other EMC parameters between switching and linear could give more acurate choice parameter
- batery properties (Nixx or Lixx or Pbxx) and charging/discharging is well documented (in french) on ni-cd.net
Thank you for the link to teh french site. I do not like this voltage notion, so I use mine. And everybody knows what I mean ;-)
I'd love to work on creating reference schematics with simulation to help people find the right Battery Supply for their project in Flux (www.flux.ai). When do you think a battery supply video will come out?
I do not know when the project team will release the designs.
A current project I'm working on requires 5 V to power the MCU and various software controlled outputs via USB as well as switching mains on and off via an isolated relay board. I may also need to add some fans for air circulation, also software controlled, which will need a 12 V supply. This video couldn't have come at a better time. Current plan is to hack a socket mount power adapter with built in USB outputs, add a fused power socket with switch, and mount a 240 V socket with switch on the back so mains devices don't need to be butchered to make them compatible. Will be able to add a ground connection too, something that is frequently absent in cheap products even if it would be desirable to have such a thing installed.
And yes, a battery version would be grand too! Many thanks.
Nice project you have!
I am very elementary to this power supply stuff and don't know a thing really. I know I need to watch what I am up to with my 3.3v and 5v sensors with my Arduino's and such - barely. But... ...a coverage on batteries would be good because with people looking for green/renewable energy resources, rechargeable battery power supplies might be of interest to some. Such very thorough work as always Andreas - thank you.
Thank you for your feedback!
Andreas your brain is like a black hole soaking up all knowledge then firing it out like a beam of inspiration across the network... thank you for sharing
Thank you for your nice words!
yes yes yes, please do a video about battery powering devices. I always have difficulties to find good booster, and if I should try to get an all-in-one board (charger & battery protection &booster), or if it is better to have everything separated. Also interesting would be a discussion in very low power devices, i.e. I have an arduino and RFM22 sending data every 5 minutes working on a single AA battery for 4 to 5 years!
Noted!
I'd be interested to see if the linear regulator is actually (electrically) quieter than a buck converter. The linear will propagate the ESP32's noise over the 12V line in addition to the keyboard power line. A switcher will usually be filtered a bit more, and might just reduce the ESP's noise more than a linear.
Maybe. I do not know.
I never knew the name of the "sophisticated Swiss guy" method! Been using that all my life. Makes things exciting, especially when I'm not looking. 😁
If you are fast you do not need to look...
I actually expected something about power supply shown on top left corner at 0:16, but it is none the less very informative!
What about powering multiple loads from single power source? I'm working on replacing dozen of power supplies 12v in network rack with single power supply which I also can keep multiple spares
If the loads need the same voltage you connect them to one supply and make sure it delivers enough current.
Awesome. Please post the batteries series and how to program esp8266 using embedded c. Thank you. Please consider my request.
Will do (not the embedded c)
Again another great video :) I’m building a large 16^3 led cube with pl9823 leds. If you calculate the power i need -> 60mA x 4096 x 5v = 1200 watt... So i bought 4 60A, 5V powersupplies, thick wire for 15A, per 256 leds. The proof of concept works. But i also want a kind of standby mode. Leds that are powered, but off, use arround 1mA... Thats 20 watt when off.... So how i was thinking using mosfets to turn all power off (need to switch the 5v, not ground, according to adafruit guide) but with 240A total those mosfet resistances RDSon will also have a huge impact. There is some overlap with battery powered project here (minimize quiescence current). Always something to learn... I’ll think i’ll go read in my electrical engineering book and figure out what to do with those huge current, but watching your youtube video’s is so much more fun ;-)
You probably need one FET per power line. Then currents are a little lower...
Battery /12volt power solutions for Raspberry pi4 would be greatly appreciated. I have already fried one pi4 😥
This should not be too complex. You just have to find a stable and capable 5V supply according to the rules shown here. Probably a switcher in this case.
I would have loved to get some information on power loss when project is in idle for always connected projects. Is there something which should be observed for such an case. For example a µC controlling multiple light outputs and most of the time standing by until lights get turned on. What's efficiency on such low power or is that something which does not matter at all?
It depends on your view if it matters. If you build one project, the grey energy inside the project is factors bigger than the standby current. And if you drive to the next supermarket you waste more energy than your project for the next 5 years... It might be different if you sell a million devices of your project.
I am trying to make a temperature sensor but it seems to work fine with a lithium ion battery but I want to use it with mains power supply and the temperature keeps jumping while I use a 2AMP power brick.any solutions???😞
Unfortunately I cannot do remote debugging :-( Maybe you check all the voltages?
Any chance you could do an episode on spread spectrum switching converters? They vary the frequency randomly around the center frequency. This lowers peak power at the center frequency and makes it easier to filter out switching noise. I've been keeping my eye out for such a project, but haven't seen anyone do a video on one yet.
I think this is too specialized for my channel and I also have no particular knowledge in this area. So somebody else has to do it.
An IR temperature sensor will give more accurate results and kill off fewer of your subscribers. Seriously, most people are much less detail oriented than you are...
I do what I love to do. And last month I got 9000 new subscribers net. So some survived...
Is it ok to use 1 amper phone charger to power ESP32 or NodeMcu directly from mains voltage?
Yes
What mobile powersupply should I choose for two of "33gb-520 12 V DC" motors?
I do not know. I would check the current requirements of the motors.
Gday Andreas. Yeah mate. Batteries next. Lipo vs li ion vs life and solar or USB charger circuits to go with them.
Lipo and Li-ion are the same, just a different name. I did already did a few videos about batteries like LiFePo4...
I keep reading on the rasberry pi forums that you should use proper power supplies rather than mobile phone chargers. Supposedly mobile phone chargers not designed to provide constant power over time. Sound bogus to me and people trying to justify the official pi psu.
These days Smartphones need much more current than a Pi. So this was probably true a few years ago. I would rather look at the max ampere.
Great review, 👍for batteries, thank you.
Noted!
All voltage regulators now have thermal protection, you do no need sophisticated Swiss method. If your device turns off for several seconds and then turns on again - your voltage regulator needs a heatsink.
Also a possibility. A little slower...
Thanks for your video, Andreas! Do you have some tests of the USB-C PD power outlets? Thinking of using a big USB-C power bank to drive my High-End DAC. But what is the quality of the USB-C outputs of a power bank?
Switching regulators and high end audio is probably not a marriage made in heaven... But no, so far I did not do any tests other than using one for my portable radio station. Works quite well at 15 volts and so far I did not have issues with RFI. But I use much higher frequencies...
@@AndreasSpiess thanks for your response. You are right regarding switch mode psu. But if running on battery from a power bank? I see some high end equipment doing that. I can't find any measurements on the quality from the power bank outlets. Br 🙂
Grüezi Andreas, many thanks (again) for this video - while I “somehow” knew how to power my projects I do now have a very structured approach to it. I’d love to see the battery video - greetings ausm großen Kanton ;-)
You are welcome. And your vote is noted.
Now we know that the finger injury was not from an accident, but from Swiss Guy temperature probing!
:-))
Lol, the swiss guy method was the 60 degrees rule during my electronics class. If you could put your finger on for 5 seconds the temperature is less than 60 degrees.
That is even more precise tahn mine ;-)
I would really really love to hear about outside battery powered projects!!!!!
Noted!
If you do the battery solutions please do one with battery backup. Power from mains if available and from the battery if power is lost.
Might be one aspect...
Very useful! Please cover the battery case. Thank you.
Noted!
thanks. I need a small hand with a white glove and an infrared sensor to check the heat for the tension regulator.
I am not sure that this modified method works ;-)
The real question is, how do you power a Raspberry Pi 4. This thing keeps nagging about low power.
I thought it is specified? If it "nags" you probably did not fulfill this requirement.
Sunday morning: sun, croissant, coffee & Andreas answering my project questions. A good way to start the day.
Thanks andreas !
Ps. From across the room my gf says you sound way younger.
Thank you for the compliment! So the investment in a good microphone was worth the money ;-)
i bought a pcb supply from a mains240 to 12v for my arduino nano. input VIN
Probably a little high. Don’t forget the Swiss Guy test ;-)
You should see Great Scott video about usb c. He explained how to create all available voltages in power delivery protocol.
I know that video and I have such boards. But I do not want to press 3 times everytime when I power my board...
A really informative video! I'd love to see you cover the other methods for power supply as well.
Noted!
What happens if I apply more than 5V volts to 5V pin. Which components can be damage?
Often, the whole MCU is destroyed. If you are happy, only the pin you maltreated.
Thanks for those hints, Battery and Solarpower would be really nice...
Noted!
A battery power supply video would be great along with another decision tree. Thanks
Noted!
Batterypowerd and solar charging. For sure! Thats still a makerproblem at all.
There are already some videos on teh channel concerning those things. Maybe a summary would be a good thing...
Meanwell makes a great range of Mains PSU's and DC to DC converters
You are right.
Hi, I ordered a switching powersupply kinda similar to the powersupply you have shown in the vid. It has 12V 5A specs. I wanted to power arduino nano using it. Of course, i would lower it to 5V using buck converter, but i'm concerned with the "5A" specs on the psu. Would it burn my arduino?
P.S. The reason i used this because I'm also about to use motor that needs 12V instead of just using USB to power arduino
Your Nano will only take the current it needs (as long as you feed it with 5 volts). No problem there.
@@AndreasSpiess I see thank you so much sir!!
I would love to see the battery (and solar) powering solutions!
Noted!
Hi Andreas, I have a P-Touch H107. Since I do not like batteries in things that I use on my desk, I have drilled a hole and connected a wall adaptor plug to the red and black cables that come from the battery compartment. I have also soldered a schottky between the red cable and the plug. The printer goes with 6xAAA batteries so I have plugged a 9v transformer and nothing happened. Whith some batteries I had around it worked and I could read 7.5v at the input. So I tried a 7.5v transformer, and a 12v and a 5v. Nothing, and the meter reads weird values at the board (like 11-15v). But the curious fact is, that with a power board (from ebay), set to 7.5v, connected to the plug, it works perfectly!! What could be going on?
I have no idea :-( But if it works it is ok, I think.
Andreas Spiess: I have tried with a variable (“universal”) adaptor ad it works fine too. In the end, I guess that I must have a significant number of broken transformers in that box 🤣🤣
Extremely helpful for this newbie!!
Subscribed!
Welcome aboard the channel!