202: Power Adapters. Finding the right one for your device. Voltage, Plug, Polarity & Power
ฝัง
- เผยแพร่เมื่อ 5 ก.พ. 2025
- In this episode, we look at low voltage power adapters of all sorts. What they are used for, and how to find the right one to match your device.
Also why you shouldn't throw out working power adapters.
Voltage: What voltage is the output
Plug: what size and shape plug does it have
Polarity: Positive or Negative Tip
Power: How many Amps?
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Finally found the right doctor for my my hobby and just being creative thank you very much.
Sir, Great video. Keep up the good work. Best wishes.
I may be mistaken, and I realize this video is edited well but I swear, I did not see homie blink ONCE in this entire video.... like damn, lubricate them eyes once in awhile bro, everybody's doing it.. lol, thnx for the info homie I appreciate cha
Maybe that’s why I keep failing those “am I human” tests… 🤣🤣🤣
I do like to edit things to keep it tight, and I guess that gets added to the unintended consequences!
Maybe I have a look on the cutting room floor and see if I can make a blink video.
2:41
No. 70th like, and a new sub... Yeaaah! Nice video. I'm also have a lot of hardware and electronics. And slowly trying to sort it out by their category of cause. And now with external power adapters. I take note of it's info printed on the power adapter. And roll the cord around it to be more compact. And then put in small to medium sealed plastic bags, and with a marker I write those info on the bag with kind of big letters. When in my age, my sight has been better in earlier years like most older folks. Plus sometime the font the use almost seems a micro-film size. Thankfully not that often. But the print can be a bit worn down, from rubbing against other electronics in my basement etc. So if really unlucky, there both micro-font used, and also a bit worn down surface. Then I can be lucky sometimes using my mobile phones camera, and zoom in. Either remember the info or take a photo. Having most of the info with volt, amps, it were nice to also get the classification of the plugs from their sizes. Having found an adaptor with the right volt, and amps, it's a bummer to get the stuff out, and then realize the plug doesn't fit (what she said 😀) . Easy to just cut the cord, and connect another plug for what you need. I did that back in the days (when I were a rebel 🙂), but also a bit stupid, if suddenly you eg. found that laptop, that has been gone for a while, and now it's right adaptor has another kind of plug connected. Better in my mind, to just sort out ones mess. And there's also the possibility to find adaptor-tips/adaptor-plugs online, and simply connect those. And disconnect easy again, since it's not hard-wired connected (or what the right word for it?!? manually spliced together?!?)
BTW: Sorry, English are a bit broken. Danish guy from Denmark.
Regards from Krusty in Denmark
Good Stuff
Thankx
FYI
Things Not mentioned, that I've learned from some experiences:
1. If you don't have a caliper. Drill bits can be used to measure the plug size your trying to determine for purchase, if you know the size of your drill bits which is labeled in the bits storage box.
2. I've had success wiring in/connecting the DC stripped end of an old transformer to a traditional disposable battery device which as no plug for a transformer. Making the battery device, battery less for some items which needed it. Connected usually where the battery ends connect. Of course if the batteries were in series then the voltage is added all together. Often the DV voltage was a bit more than the batteries so the device runs a bit faster/stronger now which is often also nice. No longer wasting batteries and our environment and wasting your $$. I see thrift stores have old transformers for sale that could be used for this.
Examples I remember, come to mind:
Cat spinning in a circle under cloth chase toy, because cat would play for hours and hours and wear batteries out fast.
Fuzz Balls remover shaver, because it was too slow especially as the batteries got weaker and batteries didn't last long and I had a whole sofa to go over!
A table light display, because it was a cheap received xmas gift that was cute but we would never turn it on because in a few days the batteries were dead.
3. If the replacement transformer is recharging internal batteries in the device it's plugging into, you better make sure the new transformer is a perfect match and has any internal regulating electronics inside it. Also you don't want it to be overpowering and recharge the batteries too fast. This could all be a safety hazard with lithium batteries catching fire these days.
Take care
Thank you for your great comment. Drill bits for sizing is one I’d never have thought of!
I did do an episode on replacing batteries here: 203: Upgrading from Batteries to Mains or USB Power
th-cam.com/video/RQoIdQ_lgKg/w-d-xo.html
Thanks for this video explanation. I have a question I am hoping you can answer. I have a Grundig Yachtboy 400 radio and have lost the power adapter. The socket is a negative tip (plus on the outside) and 9 volt, however it does not say what milliamp or amps the power supply should be. Do you have a suggestion/warning you can help me with. This radio is a good tool for long distance sailors such as myself. I also need to find the shortwave external antennae. Thanks for any help you can provide.
Googling Grundig Yachtboy 400 manual lead me to find this on page 28:
AC ADAPTOR:
Output of 9 volts DC, negative polarity (tip negative); 300
millampere current capability; coaxial plug outer diameter of 5.5
millimeter, inner diameter of 2.1 millimeter. NOTE: Using a plug
tip diameter smaller than 5.5 millimeter may not cut off voltage to
the battery compartment and can cause batteries to overheat,
leak and destroy circuits. This will void the warranty.
Thank you for that info. I happened upon the manual for the Yachtboy soon after asking you my question. It provided the info that you hjave provided. Much appreciate your help. I have a power supply on order now. All the best to you.@@TechDoctorTV
Hi, I have British model railways. I bought a Hornby controller but now need the power cord . I have had a problem locating a suitable one here in Canada. The factory cord would be this DCC Controller PU100US with the power in to the unit being 15 V
I will need to watch this over again and imagine my solution will be in here.
Is this an uncommon type?
Cheers and thanks
Charlie
I watched your video and have read up on this a bit. It's all getting clearer but I just need a little clarification. I bought a used modem/router combo (used) that had the wrong adapter cord with it - didn't fit in the port. I thought I'd try and find a replacement to test it out.
So I know I need 12V and + polarity. As far as Amps, it says 2.5A. Do I need that exact amount, a range or ? Is there a good min./max. to shoot for? Secondly, is the polarity in the tip/plug part the same as what is marked on the brick or are those two different things?
Thanks so much!!
2A might be close enough, anything over 3 might be too much. Polarity is almost always positive tip so that shouldn’t be an issue.
Hi. I lost my original ac adapter (30V output) i have one that is 32V. Do you think it will damage my device? Tks
It’s pretty unlikely! What sort of device?
@@TechDoctorTV this is the XBlue X16 digital phone system server.
My device says DC in 8.4v, and my choices on universal adapter is 9 or 7.5. Any idea which I should choose?
@@miguellasala5765 I’d try at 7.5 first and if it doesn’t work, go up to 9V
How do u find out the polarity of the device if not listed the volts and amp is listed then it has a solid line with a dotted line underneath
You really can’t. You’ll probably be safe to assume positive tip.
That symbol denotes DC Power.