I just want one that tells me the maximum voltage and current supported by a USB C cable.
there are several: one that is moderately priced and which I consider myself to buy is the JOY-IT UM120
Thanks, why do you prefer that particular model?
A nearly perfect USB cable tester
11–20 of 181 posts
Re: A nearly perfect USB cable tester
#12I just want one that tells me the maximum voltage and current supported by a USB C cable.
Got this recently for USD$3 on sale: https://www.aliexpress.com/item/1005006848187940.html
Re: A nearly perfect USB cable tester
#13The 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…
I suspect most users do not even realise things are slow.
Re: A nearly perfect USB cable tester
#14One thing to realize is that especially for high resolution video cables these cheap testers can't really deliver. The way to test them is a eye diagram (see: https://incompliancemag.com/eye-diagram-part2/ ) and testers with that capsbility cost upwards of 10.000 Eurodollars.
So you're saying there is something to audiophile grade HDMI cables?
Re: A nearly perfect USB cable tester
#15Hopefully they used connectors with a high mating cycle rating.
Re: A nearly perfect USB cable tester
#16The 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.
AFAIK that's just when plugging in a USB 3 device into a USB 2 port or using a USB 2 cable.
Re: A nearly perfect USB cable tester
#17One thing to realize is that especially for high resolution video cables these cheap testers can't really deliver. The way to test them is a eye diagram (see: https://incompliancemag.com/eye-diagram-part2/ ) and testers with that capsbility cost upwards of 10.000 Eurodollars.
So you're saying there is something to audiophile grade HDMI cables?
With digital signals and ECC, the cable need only be "good enough" to get perfect data transfer through the system.
Re: A nearly perfect USB cable tester
#18One thing to realize is that especially for high resolution video cables these cheap testers can't really deliver. The way to test them is a eye diagram (see: https://incompliancemag.com/eye-diagram-part2/ ) and testers with that capsbility cost upwards of 10.000 Eurodollars.
So you're saying there is something to audiophile grade HDMI cables?
No. What it can affect though is the bandwidth of the cable, meaning e.g. for HDMI cables, they might not support higher resolutions or framerates. If it's on the border you might see random disconnects or screen blanks.
The quality degrading is not something you will see, as it's a digital protocol.
"Audiophile grade" HDMI cables are likely to just be a Shenzhen bargain-bin special with some fancy looking sheathing and connectors. I would trust them less than an Amazon Basics cable.
Re: A nearly perfect USB cable tester
#19One thing to realize is that especially for high resolution video cables these cheap testers can't really deliver. The way to test them is a eye diagram (see: https://incompliancemag.com/eye-diagram-part2/ ) and testers with that capsbility cost upwards of 10.000 Eurodollars.
So you're saying there is something to audiophile grade HDMI cables?
No. What I am saying is that it is hard to test the quality of a 8K 240Hz 4444 video cable without having a device that can send and receive this or even higher.
If you send bits across a line fast enough you're grtting into the territory of RF electronics, with wrong connector or conductor geometry you will get echos on the line and all kind of signal loss. A good digital protocol should keep this at bay with error correction and similar mechanisms, but if you want to know what the good cable is on a better than binary scale of works/does not, you need to look at these things.
Re: A nearly perfect USB cable tester
#20I 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?