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A nearly perfect USB cable tester

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Re: A nearly perfect USB cable tester

#61
post #59

I actually purchased one of these as this article has surfaced before. It’s well worth the hype, I used it to audit all my cables (both for home and work) and it’s amazing how many thick and unwieldy cables are actually terrible for data. For example I purchased a pair of B&W Px8 S2 noise cancelling headphones, which boast a DAC if you connect via USB-C directly, the cable it came with though was thick but only rated…

Is there any audio you might play that doesn't fit in 400Mbps?

Re: A nearly perfect USB cable tester

#62
What I'm looking for is a differential signal tester, where you can breakout any arbitrary cable or traces and test the properties of the wire with different frequencies. It should be able to measure interesting properties such as resistance, capacitance, inductance, phase/length difference, wire length, etc.

One of these devices for approximately $100 would sell all day long.

Re: A nearly perfect USB cable tester

#64
Similarly: Is there a USB-C power delivery adapter to force directionality? I needed to siphon off power from small batteries into a larger pack (that could supply more power out than the small packs) in a power outage. I absolutely could not force my larger power station to accept a charge and it kept pushing power back the wrong direction despite which ends of the cable I plugged in first.

Re: A nearly perfect USB cable tester

#65
post #3

The thing that has been bothering me for a while is that the USB spec allows for software detection of capabilities. You can read the emarker data and see the supported protocols, speeds, voltages, etc. But there is not standard for usb controllers to present this data to the OS. So it’s stuck in the low level firmware and never passed up. In theory we could have a popup box that tells you that both your computer and…

> But there is not standard for usb controllers to present this data to the OS. So it’s stuck in the low level firmware and never passed up. In theory we could have a popup box that tells you that both your computer and other device support higher speeds/more power, but your cable is limiting it. There is. I used to use a KVM with USB 2 ports connected to my PC's USB 3 port, to which I connected a monitor with integr…

I've used all manner of archaic usb cables for data transfer when in a pinch and windows has never shown me anything at all. Could it be the external device you were connecting to triggering the windows notification?

Re: A nearly perfect USB cable tester

#66
post #61
post #59

I actually purchased one of these as this article has surfaced before. It’s well worth the hype, I used it to audit all my cables (both for home and work) and it’s amazing how many thick and unwieldy cables are actually terrible for data. For example I purchased a pair of B&W Px8 S2 noise cancelling headphones, which boast a DAC if you connect via USB-C directly, the cable it came with though was thick but only rated…

Is there any audio you might play that doesn't fit in 400Mbps?

The point isn’t really about audio bandwidth; it’s about the cable being strangely overbuilt for what it actually does.

It’s rigid and thick, like a Thunderbolt 3 cable, yet only supports USB 2.0 speeds and fast charging for a device that doesn’t need fast charging.

Compare that to Apple’s iPhone USB-C cable which is thin, flexible, and supports the same features.

That matters because someone might grab that cable assuming it’s a “better cable”: it came with a £629 product, it’s thick and feels serious, so surely it’s capable. But it isn’t. And there’s nothing marked on it to tell you otherwise.

The whole system ends up relying on presumption, which is exactly the problem the device in the article is solving.

Re: A nearly perfect USB cable tester

#67
post #6
post #3

The thing that has been bothering me for a while is that the USB spec allows for software detection of capabilities. You can read the emarker data and see the supported protocols, speeds, voltages, etc. But there is not standard for usb controllers to present this data to the OS. So it’s stuck in the low level firmware and never passed up. In theory we could have a popup box that tells you that both your computer and…

> In theory we could have a popup box that tells you that both your computer and other device support higher speeds/more power, but your cable is limiting it. I'm pretty sure my old Dell XPS laptop with Windows 10 had pop-ups just like this. "This device can run faster" or something.

I strongly suspected my old xps had nonstandard things going on with its USB C charger

Re: A nearly perfect USB cable tester

#68

I wasn't surprised to learn that when Linus Tech Tips released those new usb-c cables, that they all sold out almost instantly. They put their entire reputation on the line to claim (and label) the exact capabilities of their usb cables. Isn't that all we really want?

The video: https://youtu.be/OT_iyvOy0Tk

Of course they are advertising their own new USB cable, but as someone who didn't know much about USB cables I find it quite interesting.

Re: A nearly perfect USB cable tester

#69
post #66
post #61

Earlier quoted context omitted.

Is there any audio you might play that doesn't fit in 400Mbps?

The point isn’t really about audio bandwidth; it’s about the cable being strangely overbuilt for what it actually does. It’s rigid and thick, like a Thunderbolt 3 cable, yet only supports USB 2.0 speeds and fast charging for a device that doesn’t need fast charging. Compare that to Apple’s iPhone USB-C cable which is thin, flexible, and supports the same features. That matters because someone might grab that cable as…

The reason it is thick is because it supports 65W charging. Apple did the same with the USB-C cables that shipped with the pre-MagSafe MacBooks. It was a thicker cable that supported 100w charging but was only USB 2.0.

Re: A nearly perfect USB cable tester

#70
post #66

Earlier quoted context omitted.

The point isn’t really about audio bandwidth; it’s about the cable being strangely overbuilt for what it actually does. It’s rigid and thick, like a Thunderbolt 3 cable, yet only supports USB 2.0 speeds and fast charging for a device that doesn’t need fast charging. Compare that to Apple’s iPhone USB-C cable which is thin, flexible, and supports the same features. That matters because someone might grab that cable as…

The reason it is thick is because it supports 65W charging. Apple did the same with the USB-C cables that shipped with the pre-MagSafe MacBooks. It was a thicker cable that supported 100w charging but was only USB 2.0.

Can you help me understand why that would be a reason to compromise the comfort of the cable that is supplied for a device which charges at 5w?

Or, why Apple manages the same in half the footprint?

Or, why someone would expect that a cable that came with a pair of headphones actually charges things at over 65w?

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