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I want to feed USB data through a glovebox, using binding posts seen in the first picture. My thinking was that, in theory, the USB cord is just made of four wires (one for power, 1 ground, two for data). I tried cutting the cable, and soldering the four wires to banana plugs as seen in the first picture. These plugs can be plugged into the binding posts to make contact with the other side of the post and connect to the usb.

So, when I plug my cable into my computer, it gives me USB malfunction. Although this may be a stupid question, what is potentially the issue causing this malfunction?

Other than my lack of knowledge about how a USB actually works, two obvious issues include using different banana plugs on each wire, and horrendous soldering skills.

enter image description here I realize that this isnt the best picture. When I plug this cord in, I have used electrical tape to isolate the wires from one another.

enter image description here

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This is a all-around bad idea. For one thing, it will mess up the impedance of the cable. You might be able to get away with that at "full speed" 12 Mbit/s and short distances, but will likely cause trouble with "high speed" USB.

You only have 4 wires. Using only two wire colors is asking for trouble.

It looks like the bottom pair of red and black wires in the top picture are shorted together.

The bottom picture looks like you only have 3 wires connected. USB can work without the power connected if the device is self-powered, but you have to know that, and you have to know which one the power wire is.

Why not feed the USB cable thru a small hole, instead of feeding large lugs thru 4 separate holes?

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  • $\begingroup$ What is the important of the impedance? With the wires, I used what I have available. I agree its not idea. But as I said below the picture, I use electrical tape to separate the wires so they dont short. I also have all four connected but the green wire is a bit hard to see. I avoid the USB cable feed through because I wanted to avoid using an extra flange, and am nervous about leakage. $\endgroup$ – User2341 Jul 28 '17 at 17:21
  • $\begingroup$ Matching up the impedances either side of a joint in the cable correctly is what makes the signal actually travel across the joint, rather than being reflected back to where it came from. The type of construction in your pictures would work fine for connecting up a light bulb, a switch, and a battery, but it's completely inappropriate for high speed digital data transmission like a USB cable. $\endgroup$ – alephzero Jul 30 '17 at 9:05
  • $\begingroup$ "The bottom picture looks like you only have 3 wires connected." I think there are four, but the green wire is harder to see than the others. $\endgroup$ – alephzero Jul 30 '17 at 9:12
  • $\begingroup$ "I avoid the USB cable feed through because I wanted to avoid using an extra flange, and am nervous about leakage" - Just put a rubber grommet in the hole(s) to avoid any chance of physically damaging the cable. $\endgroup$ – alephzero Jul 30 '17 at 9:14

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