YOJOCK J7-C USB-C Tester & Power Meter Review

I recently reviewed the superb Anker 737 Power Bank, which is the only power bank that has 140W PD 3.1, making it suitable for the Macbook Pro 16”. I have also reviewed many new power delivery plugs that claim to do 65W, 100W or 140W power delivery and a few portable power stations with 100W PD input/output.

So being able to measure the input/output of these devices is quite important. USB power meters are handy little tools for anyone that needs to check the power delivery performance of electronics.

In the past, I was using an Innovateking USB-C Tester, which was UBS-C only and claimed to measure 0-4A 3.7-30V. This meant it could handle up to 120W, and I paid £15 for it back in 2021.

I seem to have lost this in the mess that is my office, so I recently bought the Yojock USB-C tester for the same price, but this tester has USB-C, USB-A and microUSB making it a bit more useful for testing a wide range of devices.

Preview	Product	Rating	Price
	YOJOCK USB C Tester USB Power Meter 2 in 1 Digital...	No ratings yet	£16.74	Buy on Amazon

Cheap vs Expensive USB-C Voltmeter Tester / Power Meters

At £15, it was cheap enough to be an impulse buy that I didn’t need to think about,

When looking on Amazon, there were options going up to £80, which can be linked up to a PC for more thorough data logging.

You then have a lot of options in the £30+ price range that have varying features.

My initial assumption was that the cheap options, such as my Yojock, wouldn’t be able to handle the new higher-power delivery devices. However, this can go up to 32V and 5.1A for a theoretical peak 163W input/output. However, the measuring range is officially listed at 150W, which is higher than any power delivery charger on the market, therefore making it suitable for my needs.

One of the £30+ options I looked at is capable of 4.5V-50V and 50mA-6.5A, giving 325W but claimed support of USB-PD R3.1 Extended Power Range (101W-240W).

You then have the Innovateking-EU FNB48 for around £38. This does 4-24V and 0-6.5A with a monitoring capacity of up to 156W. That doesn’t seem like good value for money, but the main difference is that it supports multiple fast charging protocols, including:

• PPLE 2.4A, QC2.0, QC3.0, PD, Samsung AFC, Huawei FCP, Huawei SCP, VOOC/WARP, SuperVOOC, and MTK-PE.

This, therefore, makes it compatible with the likes of OPPO/Realme/OnePlus and Huawei.

Due to me testing a lot of devices, I probably should have bought one of the better power meters, but this works for now and I will inevitably lose it.

Specification / Features

• The USB tester can detects voltage, current, capacity, electric quantity, power, temperature, resistance, charging time and other data of the USB or type C port devices.
• It can also be used to test the capacity and electric energy of a power bank. Measuring voltage: 3.6V-32V; measuring current: 0-5.1A.
• The USB power meter comes with A OTG adapter
• It supports PD3.0/PD2.0, QC3.0/QC2.0 and BC1.2
• Support for iPhone includes 13/12/11/X/iPhone Xs quick charging, 29W power, 5V3A/9V3A/12V2.5A/15V2A
• This USB C tester features over-voltage protection, over-current protection, under-voltage protection, low energy protection. This upgraded USB Type C tester can detect safety and maximally protect the appliances from damage

Inputs / Outputs

This has input and outputs for:

• USB-A – Input/Output
• USB-C – Input/Output
• Micro USB – Input only

Measurement Specification

In Use

The button on the tester provides such a basic functionality:

• Short press to switch different interface
• Quick 2 Press: Reset capacity (mAh)
• Quick 3 Press: Reset energy(Wh)
• Quick 4 Press: Reset timing (00:00:00)
• Quick 5 Press: Change group number (NO.X, total 10 groups of data)
• Long Press to reset capacity, energy and timing of current group(mAh, Wh, 00:00:00)
• On the system interface, short press the key to switch different setting options, long press the key to select and enter the option.

Testing Peak Power Delivery Input / Output on Different Devices

For most of the tests, I used the 140W rating USB-C cable that came with the Anker 737 Power Bank. For the Realme test, I used the included cable for the charger.

• Redmagic 8 Pro:
  • Expected: 65W
  • Result: 60.38W
• Pixel 6:
  • Expected: 22.5W (even though the charger claims 30W)
  • Result:
• Pixel 6 Wireless Charger:
  • Expected: 21W
  • Result:
• Realme GT Neo 3T:
  • Expected: 80W
  • PD Charger: 18W
  • Supplied Charger: 78.6W
• Anker 737 Power Bank:
  • Expected: 140W
  • Result:120.38W
• Huawei Matebook 13:
  • Expected: 65W
  • Result:
• EcoFlow RIVER 2 MAX:
• Ugreen Nexode 140W GaNFast Charger (charging the Anker):
  • Expected: 140W
  • Result:

Overall, I was happier with the results than I expected. I wasn’t sure the meter would pass through or read the correct values for Realme, as they use a proprietary charging standard.

The Ugreen Nexode 140W shows a lower-than-expected value, but I was only able to achieve a bit over 120W when charging the Anker 737 Power Bank.

Price and Alternative options

Preview	Product	Rating	Price
	YOJOCK USB C Tester USB Power Meter 2 in 1 Digital...	No ratings yet	£16.74	Buy on Amazon

I paid £14.90 for the Yojock USB-C tester, and it is one of the best and most reviewed options on Amazon. There are cheaper options, especially if you only need USB-C only, but for the sake a few pounds, I’d say this is worth the extra.

As highlighted at the start of the review, there are quite a lot of alternative options which cost more money but have a better specifications:

• AVHzY 3 in 1 Power Meter – This is an interesting option because it also adds DC5.5 input/output, and it has Bluetooth allowing it to transmit the data readings to an app.
• AVHzY CT-3 / CT-3A / CT-3L – This brand has three options ranking from £60 to £80. All the models can do 26V/6A (156W) though the listing states maximum power of 65W Max 100W guaranteed
  • The CT-3 supports both USB-C and USB-A input and output (the C3 model only has USB-C input/output)
  • The CT-3L includes a test load module which is programmable via the actual CT-3 module.
• Plugable Store 240W USB-C Power Meter – The only has basic functionality, but it is one of the only options that can go up to 240W with the SB-PD R3.1 Extended Power Range

Overall

For the price, the Yojock USB-C tester is excellent and exceeded my expectations, being able to read the correct power for the proprietary charging standard from Realme.

In hindsight, I probably should have paid extra for a tester with more features, but for most scenarios, especially when only testing the power delivery standard, this works perfectly well.

James Smythe( Editor-in-chief )

I am James, a UK-based tech enthusiast and the Editor and Owner of Mighty Gadget, which I’ve proudly run since 2007. Passionate about all things technology, my expertise spans from computers and networking to mobile, wearables, and smart home devices.

As a fitness fanatic who loves running and cycling, I also have a keen interest in fitness-related technology, and I take every opportunity to cover this niche on my blog. My diverse interests allow me to bring a unique perspective to tech blogging, merging lifestyle, fitness, and the latest tech trends.

In my academic pursuits, I earned a BSc in Information Systems Design from UCLAN, before advancing my learning with a Master’s Degree in Computing. This advanced study also included Cisco CCNA accreditation, further demonstrating my commitment to understanding and staying ahead of the technology curve.

I’m proud to share that Vuelio has consistently ranked Mighty Gadget as one of the top technology blogs in the UK. With my dedication to technology and drive to share my insights, I aim to continue providing my readers with engaging and informative content.

Last update on 2024-04-24 / Affiliate links / Images from Amazon Product Advertising API