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A nearly perfect USB cable tester

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Re: A nearly perfect USB cable tester

#141

Post by Telaneo »

ben_w wrote: post #139
Telaneo wrote: post #135

Earlier quoted context omitted.

Now imagine if that error said 'Error 11: A memory error occurred. Your program may be faulty or misbehaving. Contact your software vendor." That's miles better than what most things provide. That one's a good example of why these things are hard. The user could have been running 5 different programs, any one of which caused this error, and MacOS can't point the finger at anyone. Not to mention that the problem could…

This was 30 years ago, it was Mac OS classic with co-operative multitasking and zero inter-process memory protection, when the error comes up the only option was "restart" (the computer, not the task).

I know.

Re: A nearly perfect USB cable tester

#142

Post by dijit »

ssl-3 wrote: post #91
dijit wrote: 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 headphones have equivalent performance whether a USB 2 cable is connected, or a USB 3 cable is connected. The headphones themselves are not USB 3 devices; the addition of USB 3 cabling instead of USB 2 cabling would change absolutely nothing about how they work. So, no: I wouldn't expect the cable for a pair of headphones (of any price) to support USB 3. That represents extra complexity (literally more wires insi…

The Litz wire point is pretty spot on, traditional headphone manufacturers understood that cable ergonomics mattered. Somewhere in the transition to USB-C, that institutional knowledge just evaporated.

Your last paragraph is depressingly accurate though. I think that's exactly why devices like the Treedix exist: the standards bodies and manufacturers clearly aren't going to fix the marking problem, so now we need test equipment to figure out what our own cables do.

Re: A nearly perfect USB cable tester

#143

Post by [deleted] »

Retr0id wrote: post #109
dijit wrote: post #94

Earlier quoted context omitted.

I think that's being a bit uncharitable to B&W specifically; they're one of the few headphone companies where the engineering does back up the price. The cable is the odd one out.

I don't have an informed opinion of B&W either way, but are you sure it's not an instance of Gell-Mann amnesia?

[deleted]

Re: A nearly perfect USB cable tester

#144

Post by dceddia »

tetromino_ wrote: post #119

Attempting to access treedix.com (the advertised product) gives me > Access Denied > Sorry, you do not currently have the necessary permissions to access this site, or this site may not be available in your region. Are they geoblocking the USA from even viewing their site for some reason?

I was connected to a VPN and saw the same. Went away once I disconnected.

(Must say I'm not a fan of how, increasingly, taking any steps to preserve privacy is seen as deviant, or justified because bots)

Re: A nearly perfect USB cable tester

#145

Post by throwpoaster »

> The only downside of the USB cable tester is that I would love to support more plugs on the B side: USB-A (for my Frankencables) and USB B (which everyone but seems to think extinct).

Music production peripherals, until the recent USB C transition, commonly used USB B for some reason. Anyone know why?

Re: A nearly perfect USB cable tester

#146

Post by koyote »

sokoloff wrote: post #106
mrandish wrote: post #92

Earlier quoted context omitted.

> that's just when plugging in a USB 3 device into a USB 2 port Dell XPS laptops (and some others) can also warn if the charger isn't providing the full wattage the laptop is rated for. This warning is an option that can be turned off in the BIOS settings. I usually turn it off because I sometimes intentionally do day trips with a smaller/lighter portable charger which delivers 45w to my laptop which can need up to 6…

Just this morning, my old Latitude failed to boot with a “this charger is only giving 20W and that’s not enough to boot this laptop” error. (I was testing a new USB-C charger that’s obviously going back.) Weirdest part was it was 100% charged, so could have booted with 0 Watts of charger but decided not to boot with 20 Watts more.

Interesting that it refused to boot.

If I have a lower wattage charger connected on booth it shows me that information but I can just press enter to continue. It's just a warning.

Maybe it's a bios setting?

Workaround is of course to boot without a charger connected and then connect it later :)

Re: A nearly perfect USB cable tester

#148

Post by bennysaurus »

marcosscriven wrote: post #147

I haven’t yet worked out why cheap 100W PD cables partially fail after about 6 months. They can still provide some power, but between a MacBook and official Apple power supply, they’ll keep flicking between charging and not charging.

Likely the emarker chip in the cable is reporting higher power capabilities than the cable can support long term. It'll work initially but then can't maintain that after resistance in the wires increase with wear.

Re: A nearly perfect USB cable tester

#149

Post by HDBaseT »

the_biot wrote: post #52
amelius wrote: post #7

I want one that sends a pseudorandom data stream and tells me the bit error rate.

Yup, that's the sort of thing that's typically missing from cable testers. I have a USB cable that normally works fine, but introduces errors when doing full blast USB 2.0 bulk transfers. I keep it around just in case I ever come across a tester that can show me this in hard numbers.

Products that do exactly that do exist, although are prohibitively expensive. [0]

It is difficult to send 10Gbps, 20Gbps, 40Gbps or even 80Gbps, then receive it, then validate it.

[0] - https://www.totalphase.com/products/advanced-cable-tester-v2...

Re: A nearly perfect USB cable tester

#150

Post by SAI_Peregrinus »

ChrisMarshallNY wrote: post #72
mwexler wrote: post #71

Earlier quoted context omitted.

Wasn't aware of this level of testing. $1300 for a Beagle is a big step up.

That's a cheap one. Some of the analyzers can go into 5 figures. Don't forget the speeds at which modern serial interfaces go. Being able to look at the data, at that speed, requires some serious kit.

And the Beagles only do digital-domain stuff, they won't get you an eye diagram or a bit error rate. Even for USB 2.0 that's quite expensive, the test fixture from Keysight¹ is about $800, the differential probe they recommend is the $11,000 N2752A², the oscilloscope in the minimum configuration that meets the >1.5GHz bandwidth requirement they sell is the DSOX6002A³ for $24,000, and you'll also need a software option license for the eye diagram testing option. Not to mention a PC to run the USB-IF compliance test software, but that's pocket change at this point in the spending.

Keep in mind that's just for the 480Mib/s USB 2.0. If you want to test USB 5Gbps, USB 10Gbps, USB 20Gbps, USB 40Gbps, or USB 80Gbps you'll be spending much more money. The USB4 V2 GEN4 Electrical Compliance Test Specification⁴ requires a 25GHz bandwidth realtime oscilloscope with ≥80Gs/s sample rate or better. Not to mention a ≥25.6Gbps pattern generator/BERT, 20GHz network analyzer, & RF signal generator, all of which are "call for quote" but likely to be in the 6-digit price range. You're easily looking at the better part of half a million dollars to test the 80Gbps cables fully.

¹https://www.keysight.com/us/en/product/E2667B/usb-2-0-hi-spe...

²https://www.keysight.com/us/en/product/N2752A/infiniimode-ac...

³https://www.keysight.com/us/en/products/oscilloscopes/bencht...

⁴https://www.usb.org/document-library/usb4-electrical-complia...

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