USB Tester 4-28V 7A LCD USB A&C Voltage Current Power Tester Multimeter, Fast Charge Detection Trigger Capacity Ripple Measurement, PD2.0/PD3.0,QC2.0/QC3.0

Pros:1) Nice metal case with easy to use controls2) Excellent, bright and clear display, with auto-rotate3) Loads of technical capabilities4) Nice storage box to keep the unit protected5) Companion Windows app (NOT macOS) is nicely done, and turns this into a capable testing and measurement device.The only con is the documentation, which is a bit lacking. I had to go to YouTube to learn how to upgrade the firmware (which was necessary because the unit displayed incorrect temperature readings).All in all though, if you're reasonably technically savvy, there won't be any significant issues.Recommended!The manual and firmware are available at the FNIRSI website.

It's not perfect.. it has bugs, quirks, and inexplicable interactions, but --- once you figure out how to test the things that matter to you, it's very repeatable and clear.Specifically, it can read the Chip ID in USB-C cables, and show all the available power modes in USB-C PD, on a nice color built-in screen. That's nice. You can see the finer details of PD packet exchange as well, but this was less reliable.For testing batteries and other sources, it has a convenient "Trigger" function that can request any voltage or current from your supply, with a nice physical Switch that engages or disengages the "active" part. Switched off, the device is pass-through only and zero risk. Switched ON, you have a lot of direct control over voltage, and of course, risk. You want to put 20v on a USB-A socket? You can!I find the device is best to use when it's plugged into its own independent Micro-USB power source (5v, low current), because then it's not constantly turning off and on with your devices under test.It's easy to crash the device when messing with USB-PD packets, or even have it just beep nonstop until you pull power. The firmware could use some work. Some functions are duplicated or confusing (how many different trigger menus do you need?) but hey, it's affordable for DIY hobby work and comes in a nice well-made housing with an excellent screen for cheap.Unfortunately, the company web site is terrible, hosted on some Mediaflare thing that runs out of bandwidth, so downloading the firmware updates is way more hassle than it should be. They need to up their game, put up a professional site, and host their own files.

First, this is a very capable little tester. For testing USB-A stuff, no complaints at all. Does what it says on the box and then some. There are even Python libraries that can read the data over the USB port so you don't necessarily have to use an app downloaded from a strange place to access the data.My only complaint - and it may not be the device's fault - is the situation with two USB-C cables. It can be difficult and require some trial and error to actually get a proper USB-C PD connection passing through the device. As I understand it, this is because despite common belief, USB-C cables *aren't* 100% reversible (i.e. flipping the connector 180 degrees doesn't always "just work" because some pins are only connected on one side of the connector) and this is one case. It might take you up to 16 tries (four connection points, two possible orientations) to actually get USB-C PD passing through the device even with the device's own PD negotiation turned off. At best you'll get 0 volts, in the middle you'll get plain 5v/2a power, and in a couple cases I saw the device crash or fully shut down even with external power provided via the PC port.In short, you need two full-function USBC-to-USBC cables to be able to passively measure charging between a USB-C charger and device, and you might have to play with reversing the connectors multiple times before you actually get a successful PD negotiation.I'd love to see a USB-C native version of this, with a USB-C port or cable directly attached to the device so you never have to worry about the two-cable pass-through situation. I do have a TC66 USB-C tester which works well but its UI leaves much to be desired compared to this one!

My experience with scopes is pretty limited, so take this as the opinion of a FW/SW dev.I love this little guy. Power consumption measurement of MCUs has been elusive until now. The sampling resolution doesn't blow me away, but it is good enough for my needs. Very easy to read and use. I found the menu system on the intuitive side, which surprised me.A like its size as well. At first I was wishing for a bigger screen. After using it for a while, I found that the smallish size is great because now I can leave it connected all the time without hogging up desk space. Excellent. And for the record, I've seen no evidence of interference with MCU D+/D- signals.Wish I'd picked this up a long time ago.

Exactly what I needed

Bright easy to read display. I have already found defective cables using this meter. It solved my slow charging problem. Has many functions that I probably won't use, but they are there if I need them.

Llegó rapidisimo en perfecto estado...funciona bien