YOJOCK USB C Tester USB Power Meter 2 in 1 Digital Multimeter 3.6-32V 0-8.0A Voltage and Current Tester, Type C Voltmeter Battery Capacity Volt Ammeter Power Bank USB Cable Charger Detector

I've used this a hundred times to sort out various USB issues, like compatibility problems that prevent charging at 9V. Simple to use, clear display, and compact to fit my tool kit.

I juggle a ridiculous number of gadgets that all want to charge at different voltages, speeds, and cable types — plus a whole ecosystem of motorcycle gear (helmet comms, heated vest and glove batteries, the works). Some of the newer devices even negotiate up to 10V instead of the usual 5V, which makes guessing what’s happening behind the scenes a losing game. This little tester has been a lifesaver. It lets me see exactly what’s being pulled, what voltage a device is negotiating, and whether something is actually charging the way it claims. At home or on the road, it’s made managing the chaos a whole lot easier.

Works just as it should and has helped me tremendously since I got it. So if you need to check usb voltage or amperage this is a handy tool for you to have. Save you tons of time and money on the cords and chargers foe your usb powered electronics.

I've used this device thus far to measure current going to my USB device. Very interesting. May want to get some short USB extension cables to avoid plugging this directly into your computer's USB ports (unless you really need to.)

Love this. Any tinkerer or anyone who enjoys having a little more info will enjoy this. I installed new USB ports in my car and it wouldn't charge our Nintendo Switch. With this tool, I was was able to determine that thsoe USB ports were pushing out ~5.5V, unstable at that. The phone and tablet charged fine, but the Switch is fickle about charging. I have found it works great, but I can't get the micro-USB to show AMPS. The video shows the unstable, high voltage on this cheap panel-mount usb port.

This is my first time using a USB power meter, and I was pleasantly surprised that 1) the built in color display provides a wealth of info, and the tester includes the most popular USB connectors. I am seriously impressed.

I used this tester to check a bunch of USB chargers I had. Several were outputting overvoltage or undervoltage, and a couple had large amounts of ripple current. This allowed me to get rid of a few that were under-performing, as well as separate the high-ripple units from sensitive applications, like powering audio gear. The mini-oscilloscope function is great - a picture is worth a thousand words, and this is a huge time-saver.

This was delivered on time. I misunderstood a few things in my testing and the manufacturer was quick to respond to my questions. I believe that I tested every J7-c configuration. While I cannot vouch for the accuracy - it did what I needed - I can state that everything worked. There are some limitations in the device, but more on that below. Most of the limitations seem to be due to destination plug standards. USB to J7-c to USB to lightning Input - I tested this with both a powerpack and plugged into the wall charger Output - to a magnetic charger for an Apple Watch Result - perfect USB to J7-c to Type-C to lightning Input - I tested this with both a powerpack and plugged into the wall charger Output - to a iPad Result - perfect Type-C to J7-c to USB to Apple magnetic charger Input - I tested this plugged into the wall charger Output - to a magnetic charger for an Apple Watch Result - no output, however, the manufacturer told me of this limitation: "Apple devices don't support charging like this because Apple’s charging system is strict, it with a charging identification chip. If you use this usb tester to test Apple devices, it only supports Type C-Type C-lightning or USB-USB-lightning or USB-Type C-lightning." Type-C to J7-c to USB to mini Input - I tested this plugged into the wall charger Output - to a Garmin Result - same as last test, probably due to same "standards" limitation Type-C to J7-c to USB to micro Input - I tested this plugged into the wall charger Output - to a powerpack Result - same as last test, probably due to same "standards" limitation Type-C to J7-c to Type-C Input - I tested this plugged into the wall charger Output - to a iPad Result - perfect MicroUSB to J7-c to USB to USB micro to a powerpack Input - I tested this plugged into the wall charger Output - to a powerpack Results - Success MicroUSB to J7-c to USB to Type-C to a magnetic charger for an Apple Watch Input - I tested this plugged into the wall charger Output - to a magnetic charger for an Apple Watch Results - Success MicroUSB to J7-c to USB to USB mini to a Garmin Input - I tested this plugged into the wall charger Output - to a Garmin Results - Success MicroUSB to J7-c to USB to USB mini to a magnetic charger for an Apple Watch Input - I tested this plugged into the wall charger Output - to a Garmin Results - J7-c showed input power level, but no output power created In summary, a) the J7-c with USB input worked great for all output types I tested b) the J7-c with Type-C input worked fine when the output was Type-C c) the J7-c with MicroUSB input d) J7-c use with Apple Lightning can be problematic This fits my needs now that I know the limitations and I recommend this to other users.

Funciona a la perfeccion, para saber la carga de diferentes cargadores que tenia por casa y en la oficina, asi puedes comprobar si realmente cargan a la potencia que dicen. Da mas informacion de la que necesito, es muy completo y esta hecho con calidad, buena compra.

Gebruiksvriendelijk, nuttige informatie over laadstroom, lader capaciteit en over ondeugdelijke kabels!

Purchased this to test the USB-C ports on my Mac and phone after experiencing charging problems. The tester provides clear voltage and current readings, which made it easy to identify whether the fault was with the cable, charger, or device port. Having both USB-C and USB-A support is very helpful as it works across all my chargers. Straightforward to use and very informative. A useful diagnostic tool for anyone troubleshooting charging issues.

Underbar sak som gör sitt jobb väl. Där ser man om det drar någon ström eller inte laddar alls. Bra verktyg.

It is working now, it looks very good, for how many days the display and device work well ❤️‍🩹