CY UC-022-0.9M USB 3.1 Type-C Female to USB 2.0 A Male Cable (90cm) (Rant #R1)

Oooh, look at that precious hellspawn!

“USB-C to USB 2.0 Data Cable for Macbook Tablet, Mobile Phone – Black” – capturing everything that is wrong with USB-C!

Sure, carrying over the perfectly fine USB 3.0 spec into USB 3.1 and calling it “Gen 1” (in contrast to “USB 3.1 Gen 2” that is double the speed) is a huge fuckup on its own. There’s no better way to screw up a customer by allowing manufacturers to call something USB 3.1 compliant (new! shiny!) when it’s just 3.0 with a new badge. […]


26650 LiFePO4 8S battery pack with BMS (WHL #27)

This weeks article is another by-product of the ADC testing (WHL #26) from last week. Could’ve packed in there, but I wanted to share some remarks on Chinese battery technology…

So first of all, this isn’t a piece of kit that I bought myself. After testing two 12V/2.2Ah lead batteries from work that were sitting unused on a shelf for five years, I needed another victim. Those quality Panasonic cells were flat as Kansas – the LC-R122R2PG datasheets recommends 8.6V cutoff voltage at 3C = 6.6A or 9.7V at 1C. Fully charged, they delivered 1C at 7V or 1.5C at 2.5V at full charge – slow 10.5V discharging to 0.1C cutoff and recharging didn’t help much. […]


16 Bit I2C ADS1115 Module ADC 4 channel with Pro Gain Amplifier RPi (WHL #26)

Meep. We finally have a new product review, after all that editorial, recap and electronic load rubbish ;)

Today’s item in the mail is an I²C ADC on a small PCB, running four channels (or two differential ones) with 16 bit precision. Sounds nice? Well, if it holds the claimed specs, it IS a nice product! I bought it in mid-June on AliExpress for 2.06 USD. Adafruit, by the way, charges 15 bucks for the exact same thing. Do I smell profit margin?

Here’s how it looks straight out of the ESD bag:

Backside is a tad boring (keep the VDD in mind):

(there’s a floating island on the GND plane, boo!)

So, what does the friendly Asian seller claim? […]


A beefy electronic load (#P4F2)

Hello again!

I’ve been asked: What do you do with this electronic load thing? Well, I‘ve been using it as a battery torture device, what else could you do with a variable resistance device…

For a crude first step in actually testing my unit and also classifying a newly harvested set of deeply discharged 18650 cells, I slapped together some minimalistic Arduino program and hooked the thing up in parallel to the battery under test. The electronic load was set to 2 Amps with another battery, which was monitored by the Uni-T 203A current clamp. […]


A beefy electronic load (#P4F1)

Well, that was a long week…actually, it was a fortnight ;)

Here we go!

(the alignment of images really sucks when placed near the header of the post – thanks WordPress!)

So this puppy was manufactured by my new friends over at OSH Park (ordinary order, no extras) and I think I hit the express jackpot. I registered on June 8th and submitted my files – three hours later (1 AM my time on Friday) I already got notice of the panel assignment. Maybe the small size of 54mm x 31mm (2.1″ by 1.2″ for the Yankees out there) just made a perfect fit on the remaining board size and they sent it straight to production ;) As OSH Park charges 5 dollars per square inch of board area (for three units!), these were 12.75 USD including the free standard shipping. […]


A beefy electronic load (#P4)

This is a ranty introduction to the electronic load project – photos, circuits and more will be available in part 2 next week!

So…I’ve been torturing power supplies (and to a lesser extend: batteries) for ages. Usually to check their health status by comparing the current peak performance to the claimed values in the datasheet. Once you see voltage rails dropping where they should not, it’s time for a replacement of the unit, or in case of specialized PSUs, for a swap of the electrolytic caps.

But the crudity of my testing always bothered me – hooking up power resistors, measuring voltage and current, manually connecting and disconnecting the DUT, never hitting exact performance figures because of the limited selection of torture devices I had around. […]


Lenovo Thinkpad R400 LED Display backlight fix (#P3)

Yes, it’s running in the “projects” category, as “quick and dirty weekend fixes” isn’t available yet :mrgreen:

While I was hosting my brother, he casually asked me when I will fix his display. Umm…what?
Turns out, his Lenovo R400 was showing vertical stripes again. Like these:

(jup, stolen from some Apple customer help page – I didn’t take a photo at the time. I guess the bug is a watermark, isn’t it?)

I’ve already seen and kind-of fixed that on my visit shortly before Christmas last year, when I basically had no tools available. […]


Back! Well, sort of… (#E4)

Hey folks, I’m back! ;)
Two months off the blog seemed like a long time, but actually it wasn’t. After filing taxes and hosting my brother for a week, I also got snail mail from the long-forgotten dispute with the German propaganda agency “ARD ZDF Deutschlandradio Beitragsservice”, formerly known as GEZ. And as they finally decided (after 1.5 years!) that they don’t care about my arguments and they also snooped my new address from the registration office, they let me know. I had the choice between accepting paying 18€ A MONTH for one-sided fake news that I don’t listen to (not even having a TV or radio to do so) or to start a pointless legal battle – so I went to court to just do that. […]


Death and Taxes (#E3)

Well, not the Path of Exile map that screwed me over last week because animated weapons friggen fly above the ground and are entirely unaffected by my sparker build…no, it’s about the real taxes that are as certain and inevitable as death itself.

Apparently, it is that time of the year where the German tax authorities want the tax declaration for the last year, so I got to comply if I do not want to be fined. As this is my first real (required) filing, I need some time off to prepare the documents. I did one voluntarily for 2012 last December, but that’s not legally decided yet…5 months are indeed a very short amount of time to decide about a few thousand Euros spread across maybe 50 pages of paper :) But the mills of bureaucracy like to be fed well, and so I’ll pour in documents for tenfold that amount this time. […]


Müller Licht 5.5W/220-240V/50Hz/38mA/470lm/2700K/dimmable/E14 EB1500665 40036 (WHL #12F2)

Well, I guess I was onto something when I first complained about the failed E14 LED bulb back in WHL #12
Not only did the second one (out of four) die as shown in the followup #1, but now the third one is dead as well. And, which is my favourite part, the replacement for it was almost DOA as well. It blinks every few second and never fully turns on. What a heap of garbage!

So naturally I complained again ( :twisted: ) , and the guys from voelkner played the cheapest “shut up” card possible – they did a complete refund of the four initial light bulbs without any further questions asked. […]