Reserved

angerdan wrote:

dodge_911 wrote:

the new green YZXStudio meter with bluetooth

Do you have a link?

Get it from Franky Tong, he’s a very reputable seller in eBay, fast communication and shipping. Shop name 99centhobbies / f-t-2000

This is the newest version with built in Usb cable resistance metering

http://www.ebay.com/ulk/itm/201517862132

I have spoken with Franky (probably the main overseas distributor for yzx products) and he tells me the Y1270 color oled version is still in its very first FW versions, and that it’s best to wait for a couple upgrades to have bugs sorted out and get a more accurate calibration. Anyways I think one could upgrade it at home with an ST usb programmer, the new FW archives are posted on chongdiantou chinese forum.

Here’s the Y1270 with some more specs on the official store: http://world.taobao.com/item/527344581834.htm?fromSite=main&spm=a312a.77...

I also ordered some interesting yzx products that I will review once they arrive, a YZX 7th gen 4-cell powerbank, the fan-cooled usb dummy load and the new Y1266 meter.

JamesB wrote:

99centHobbies ebay store seems quite expensive , YZXstudio stuff is double the price compared to taobao and prices discussed in the chinese forum.

I’ll be totally in for a YZXstudio group buy.

You’re right but communication with him is really easy and quick, he also provides a custom translated user manual and flashes the meters to the latest FW version available before shipping. Some other sellers don’t even know which version they’re shipping…

To buy from taobao you can use mistertao agent, but the only time I used it the item took 3 months to arrive, and they don’t accept paypal.

I could ask him for a possible groupbuy but I think it’s been asked before on EEVblog forum and it didn’t went on. But even at $30 this meter is totally worth it! Here’s the official sales thread: http://www.eevblog.com/forum/buysellwanted/franky’s-sales-thread/

Hi everyone, since there’s an ongoing talk about the newer versions of the USB power meter and other YZXstudio gadgets I decided to turn this thread into a general discussion about YZXstudio devices. I have removed my powerbank tests which were not very relevant to the usb meter and will start a separate thread for all my existing and upcoming reviews.

So this is will be more or less an “Official” YZXstudio thread for BLF if you’re ok with it, since the users for these devices are limited I thought it is best to keep all the information and talking in one place. I will add an index to the OP pointing to reviews/first impressions/new products in and out of this thread, and since this is not my personal review thread anymore, please feel free to ask or add anything related to this.

What do you think?

I just received the YZXstudio 7th Gen 4-cell powerbank. The construction of this thing is top notch, and the available settings is astonishing! The most remarkable configurations are:

-Set output voltage for both 5V and QC 9V (-+0.5V)
-Set discharge cutoff voltage, charge termination voltage and current.
-Set battery charge current up to 4.5A (1A+ each)

I’m still trying to figure out some of the calibration features (the UI is in Chinese only), but so far I have correctly calibrated battery capacity and battery full voltage.

4x Sanyo GA as battery source

1× 5V & 1× 9V USB out, microUSB and 4mm input (shares the same plug as the sony PSP).

Empty

Loaded

Close-up of the board, some of the components are never seen in any powerbank before.

I calibrated the internal voltmeter to match my most accurate DMM and the skyRC MC3000. It tops the battery at 4.207V

I haven’t done all of the output testings but I did a quick discharge test at 1.5A and got 94.2% efficiency. This is the highest effieicncy I’ve seen not only in a powerbank, but in ANY DC-DC boost converter.

Battery capacity as measured by MC3000 at 0.5A discharge rate, with D-reduce of 250mA down to 2.5V: 3380mAh, 4 of them makes 50.02Wh. Note that the sanyo GA does not reach the spec’d 3,500mAh in real discharge tests.

Output at 5.15V 1.5A by using the YZX dummy load: 47.12Wh

So far I’m amazed by the performance of this powerbank… to be honest this is one of the finest electronic device I have ever used. Will soon upload more discharge tests.

At $60 and $25 for batteries it is not remotely budget, but it’s worth every cent!

I’m after Gen 8 as well, I like that a specialized DC adapter can be used to charge even faster than Quickcharge 2.0 or 3.0. The fastest charger I have for mine now is a 9V 2.5A car adapter for 22W+ output, even faster than a quickcharge adapter at 9V 1.8A. Both can allow the powerbank to push 4A to the batteries.

I’m using the google translate app, but some settings are translated as “Setting reference full power voltage”, so I really don’t know what that’s for.

I also got the ZL1000 dummy load with the upgraded Bourns multi-turn trimpot, so far it works as expected and runs relatively cool. Supports QC2.0/3.0 with auto coding request. Will upload a review after some more extensive use.

I got the YZXstudio 1270 Color OLED meter with Bluetooth a couple days ago and have been playing with it a bit… Since all the technical aspects have already been covered in HKJ’s review I decided to write a quick guide for importing the raw data from the bluetooth terminal and use them to make a graph in excel.

1. Enter the settings menu in the meter and set the serial upload rate to anything but zero. My preferred interval is 30sec.
   
2. Search and connect the meter to your smartphone, will be listed as SPP-CA.
3. Download and run Blueterm app, long press the screen to select the device and start logging.
4. Once done with logging the data, copy the file to your computer and rename the format to *.txt.
   In the file you’ll see the raw data like this:
   
5. Open Excel, select “Data” tab and then “From text”
   
6. Select your .txt file and then “Comma” as the delimiter
   
7. After that you’ll get two lines of data displayed in ten thousandth, so divide by that and set the decimal places you like. Add time axis as well.
   …….
8. Final step is to create the graph of your liking and you’re done! Note that I placed the AMP value in a secondary axis.

—-

In this graph you can see how this powerbank fails to deliver a healthy voltage half the discharge cycle at a 1.5A rate, dropping from 5V to <4.3 is unacceptable.

The meter doesn’t send other important parameters such as capacity and energy, but you can calculate them using simple formulas. Here’s another example, rate set at 10sec this time.

dodge_911 wrote:

will34 wrote:

I got the YZXstudio 1270 Color OLED meter with Bluetooth a couple days ago and have been playing with it a bit… Since all the technical aspects have already been covered in HKJ’s review I decided to write a quick guide for importing the raw data from the bluetooth terminal and use them to make a graph in excel.

Thanks for that! It’s usable for any of the YZXStudio meters that have bluetooth too Now I need to buff up some on my excel (numbers) and math skills to figure out the formulas you used

It’s pretty easy… for Capacity (Ah):
First value: C = Current / records per hour
Then:
C1 = C + (Current / records per hour)
C2 = C1 + (Current / records per hour)
And so on… just drag down to replicate the formula for all fields

Records per hour = 3,600/serial upload date

For Energy is the same, instead of current use power.

Once you have the chart done just simply import new data for whatever you’re going to test. There is a very small variation in this calculated value vs the measured value displayed in the meter, but even at 10s refresh rate the variation was only at <1%. At 0.36s refresh rate the tolerance should be near zero, but that’s a lot of values to work with.