You can have a short, and the circuit can still work. Electricity doesn't take the path of least resistance, it takes all paths proportional to resistance.
When you short a circuit, you're creating a parallel path, but current will still flow through the other path. Sometimes the short limits the current on the intended path enough that the device doesn't function properly. Sometimes you have protection built into the system that opens the circuit in the event of a short. Sometimes the short causes something to let the magic smoke out.
But a short won't necessarily kill all circuits. They wired a battery to a USB cable using screws, so I think we can assume they don't have anything that will kill the circuit in the event of a short. It is entirely possible that this worked for testing purposes long enough for them to call it a proof of concept.
The device needs probably about 4.5v at least to function, so you would probaly loose over 500w at the housing to get to that voltage, and you would basivaly start a fire imedeatly
Thats not how circuits work though. When you create a short, you are creating a parallel path. Voltage is going to be the same across both paths by nature of being a parallel circuit, and is determined by how charged that 9V battery.
The device itself most likely accepts up to a 9V connecting and then internally regulates the voltage down to what it actually wants to use. The short has no such regulation and will just be operating under the full voltage the battery gives.
In theory a short is effectively a 0 ohm path, but this is shorting a USB housing through screws, you're going to have somewhere between 1-3 ohms of resistance for that path. The resistance gained from using a poorer conductor like the screws is exactly what makes it believable that they got this to work for a second as pictured. Really, worst case you'll have about 9A going through the short.
They posted a video of them doing the same thing with Allen keys attached to the battery and guess what? The lights turned on even though they were surely shorting the housing while using those as well. No magic smoke let out in the video. Yeah the lights weren't constantly on, but I'm willing to bet that was from opening the circuit while moving the Allen keys around rather than shorting it.
Most people in reddit have no concept of electronics, you're fine dude although I would have been easier just to strip the cables and connecting it to the power supply like that
Yes! This was my very strange proof of concept for a battery powered mini Christmas tree. My fiance had restrictions preventing her from plugging electronics in at work.
Why not just use a USB power bank? And connecting up a 9V battery as in your video will likely be overdriving the LEDs which can kill them quite quickly.
Not to say that this is impossible, but from this angle, it's hard to tell if it's legit or not. The USB shield is made of metal. If there isn't some price of insulating material keeping the screws from touching the metal, the two screws will be connected together. Electricity takes the shortest path, it would completely skip the device being powered if the two screws are directly connected by a piece of metal.
Edit:
Additionally their video of proof shows this exact issue in play, it only lights briefly, because the power leads are shorting against the metal most of the time
Also, they used thinner pieces of metal for the video. This leads me to believe the one shown in the posts picture would not work at all.
Geeeze guys. I didn't mean for this to be an attack on OP.
I just wanted to know how he kept the screws from shorting.
It's a very valid post to the subreddit.
Man, IDK what you want from me. Lucky I even had that video I made for a friend. This is a completed project from a year ago. Like, what, dude? I've decided to go REALLY out of my way to fake this???
No, just the particular iteration with the screws wouldn't work and you probably forgot. You then made it work properly, and the interim steps are remembered very vaguely.
Well, I won't rule out the possibility I'm recalling things incorrectly. But, I *feel* like I remember being happy the screws worked. I never tried hotwiring a USB and I was happy it proved I could use a battery.
One way or another, I apologize for the tone. You were respectful to me and deserve that in return.
idk if it's necessarily being too harsh or you just posting something you did in a sub about unnecessary/dangerous/dumb diy and expecting people not to see it that way
Would you mind going into more detail? I figured if I did something wrong the worst that would happen is a mild 5-9V shock. Was that incorrect? Could it have been worse?
Because two screws threaded into the metal box of a USB plug will cause a short. Your "proof" video uses two hex keys that you're holding. These are not the same.
Once, when I was homeless, my phone died because I forgot to charge it at work and the library was closed. So I bought a pack of 8 AA batteries.
I taped 2 sets of 4 together in series and then connected those two sets in parallel. So the output was about 6v.( I didn't wanna push my luck and damage my phone).
Then I stripped a USB cable and taped the +/- wires to their corresponding paperclip, and plugged my phone in. To my amazement, it actually worked. (Albiet quite slowly), but I was able to play on my phone and have my alarm wake me up the next day
How does this not short out the power through the connector housing?
my guess is that pic is actually concept. op's comment where they ended stripping the cable makes it true diy.
You can have a short, and the circuit can still work. Electricity doesn't take the path of least resistance, it takes all paths proportional to resistance.
When you short a circuit, you're creating a parallel path, but current will still flow through the other path. Sometimes the short limits the current on the intended path enough that the device doesn't function properly. Sometimes you have protection built into the system that opens the circuit in the event of a short. Sometimes the short causes something to let the magic smoke out.
But a short won't necessarily kill all circuits. They wired a battery to a USB cable using screws, so I think we can assume they don't have anything that will kill the circuit in the event of a short. It is entirely possible that this worked for testing purposes long enough for them to call it a proof of concept.
The device needs probably about 4.5v at least to function, so you would probaly loose over 500w at the housing to get to that voltage, and you would basivaly start a fire imedeatly
Thats not how circuits work though. When you create a short, you are creating a parallel path. Voltage is going to be the same across both paths by nature of being a parallel circuit, and is determined by how charged that 9V battery.
The device itself most likely accepts up to a 9V connecting and then internally regulates the voltage down to what it actually wants to use. The short has no such regulation and will just be operating under the full voltage the battery gives.
In theory a short is effectively a 0 ohm path, but this is shorting a USB housing through screws, you're going to have somewhere between 1-3 ohms of resistance for that path. The resistance gained from using a poorer conductor like the screws is exactly what makes it believable that they got this to work for a second as pictured. Really, worst case you'll have about 9A going through the short.
They posted a video of them doing the same thing with Allen keys attached to the battery and guess what? The lights turned on even though they were surely shorting the housing while using those as well. No magic smoke let out in the video. Yeah the lights weren't constantly on, but I'm willing to bet that was from opening the circuit while moving the Allen keys around rather than shorting it.
Most people in reddit have no concept of electronics, you're fine dude although I would have been easier just to strip the cables and connecting it to the power supply like that
That is what I did in the end! I even integrated a little switch from an old fan. I seemed to have wired it backwards, but hey, it works!
https://i.imgur.com/zX1JtS0.png
So it sucks, doesn’t blow?
Sucks power and doesn't blow fuses... thankfully!
that’s what i’m sayinnn
I got shit on here once for wiring an old poopy pc mic to our baby monitor when its mic died. Somebody said it was dangerous lol.
does this work? asking for a friend
Yes! This was my very strange proof of concept for a battery powered mini Christmas tree. My fiance had restrictions preventing her from plugging electronics in at work.
Why not just use a USB power bank? And connecting up a 9V battery as in your video will likely be overdriving the LEDs which can kill them quite quickly.
Honestly, money is tight and I was just using the resources I had. A powerbank is a much better solution. I just didn't have one.
I don't believe you. Did you put something in the plug to keep the screws from shorting?
In case you didn't see the reply below, here is proof (Sorry it's so long. Very hard for me to film alone)
https://i.imgur.com/C1DRvSr.mp4
Dunno why people have such a hard time believing you.
IDK either. Like, I did something stupid. Why is that hard to believe, lol
I think they just have absolutely no understanding of how this stuff works. So they see something like this and just assume its fake.
No. It's more that I work with this stuff every day and know the screws will short if it's used the way it is in the picture.
Because it breaks the laws of physics? The screws are clearly shorted through the housing.
both are literally touching the metal, it will short out
Not to say that this is impossible, but from this angle, it's hard to tell if it's legit or not. The USB shield is made of metal. If there isn't some price of insulating material keeping the screws from touching the metal, the two screws will be connected together. Electricity takes the shortest path, it would completely skip the device being powered if the two screws are directly connected by a piece of metal.
Edit: Additionally their video of proof shows this exact issue in play, it only lights briefly, because the power leads are shorting against the metal most of the time
Also, they used thinner pieces of metal for the video. This leads me to believe the one shown in the posts picture would not work at all.
The screws will just short against the casing, hence my comment :P It's womderfully janky and worthy of the thread.
XD Thanks
Geeeze guys. I didn't mean for this to be an attack on OP. I just wanted to know how he kept the screws from shorting. It's a very valid post to the subreddit.
Believe what you want. I didn't put something in to keep the screws from shortening. It just worked.
Press x for doubt
Here's proof (Sorry it's so long. Very hard for me to film alone)
https://i.imgur.com/C1DRvSr.mp4
Video doesn't show screws. And, as expected, the light is not on when the red leaf is touching the metal body.
Man, IDK what you want from me. Lucky I even had that video I made for a friend. This is a completed project from a year ago. Like, what, dude? I've decided to go REALLY out of my way to fake this???
No, just the particular iteration with the screws wouldn't work and you probably forgot. You then made it work properly, and the interim steps are remembered very vaguely.
Well, I won't rule out the possibility I'm recalling things incorrectly. But, I *feel* like I remember being happy the screws worked. I never tried hotwiring a USB and I was happy it proved I could use a battery.
One way or another, I apologize for the tone. You were respectful to me and deserve that in return.
Jeeze, man. I didn't expect this sub to be so harsh. Yeah, I'm gonna go out of my way to make a fake post on this niche sub /s
idk if it's necessarily being too harsh or you just posting something you did in a sub about unnecessary/dangerous/dumb diy and expecting people not to see it that way
DC current is not "dangerous" at that voltage/wattage. Not even remotely.
Ah yes 5 volts very dangerous
Tbf It can be at 1000 amps. Don't ask me how I know.
Would you mind going into more detail? I figured if I did something wrong the worst that would happen is a mild 5-9V shock. Was that incorrect? Could it have been worse?
That's fine. I too think what I did was dangerous and dumb. This is clearly reckless. I just don't know why everyone is calling me a liar.
Because two screws threaded into the metal box of a USB plug will cause a short. Your "proof" video uses two hex keys that you're holding. These are not the same.
Screws and hex keys are both metal, they can both pass current
The shape of the metal doesn't matter, the electrons don't care
Don't worry, people are just dumb N coming from someone who does equally janky shit sometimes. Lol
Why do you guys not believe this? I do junky shit like this a lot of low power devices. It's reasonable
because the metal screws are touching the metal on the usb and would be sorted together.
Respect
Once, when I was homeless, my phone died because I forgot to charge it at work and the library was closed. So I bought a pack of 8 AA batteries.
I taped 2 sets of 4 together in series and then connected those two sets in parallel. So the output was about 6v.( I didn't wanna push my luck and damage my phone).
Then I stripped a USB cable and taped the +/- wires to their corresponding paperclip, and plugged my phone in. To my amazement, it actually worked. (Albiet quite slowly), but I was able to play on my phone and have my alarm wake me up the next day
Your phone survived because of the batteries’ high internal resistance. The voltage likely dropped below 5V.
Wow, actual DIWHY and not some stupid ragebait bullshit from tiktok.
THIS is what this sub is SUPPOSED to be.
Thank you, OP.
Thank you!
Looks unhinged. Well done!
Lol thank you!
Hey, 5 V is 5 V…
It's not 5V though they connected it to a 9V battery
i wish r/doohickeycorporation allowed cross pisting
Feel free to repost 😁
Bungler-level 9000. Love it!
I recommend you buy this and then wire it to the 9v battery lol. Just to be fire safe 😅
https://www.amazon.com/Cigarette-Replacement-Voltmeter-Waterproof-Motorcycle/dp/B0CTD84F3P/ref=sr_1_17?crid=217GX6RLCGVNI&dib=eyJ2IjoiMSJ9.GYRKQ6BGsWIZX0GQ4KXNfjovZRqAceXALofbLn2Qu9nL0a-tbKdiBMg0jqQWmiKn--GUYJSX8xsVs1F3OUKmQ3jZthTzUaHXG561tjrZDfPRd7OX-neVwNU0cVhfCCEddTGF518-T4lyWw9K2b4MnpmNqDhZRBhmBjB7WqTcj251DjzqxQzNr7I3r_PNE5uncEMUh2A3zrttefqEKkt2dKRLn4xJuOl7WLB1mrLX5Js.qxVlPGoqWApzUz4lGRXcPaYHC9fUDOL9qENzfKvXJEI&dib_tag=se&keywords=usb%2Bcar%2Bplug&qid=1765148083&sprefix=usb%2Bcar%2B%2Caps%2C315&sr=8-17&th=1
I'm guessing not in pictures is the homemade USB to 120V plug?
Assuming you're using USB 2.x for this as 3.x would have the risk of shorting pins 1 and 7.
Yeah. There were only 4 pins.
i guess it's better than chopping the cable?
Not really, lol
In fact, that is what I wound up doing