The Tale of “Nitecore” Keychain LED lamps …

Once upon a time there was an overly enthusiastic browser of ebay items, instigated by “BigClive” to buy stuff. He purchased two Nitecore knock-off lights, a bit too cheap to be true!

The packaging looks surprisingly good. Guess which one is the real thing. While waiting for the stuff from China to arrive, he also purchased a set of 2 genuine Nitecore “Tube” lamps on Amazon. This will turn out to be crucial.

[…]

Several months later (sponge-bob narrator voice).

Well, I got busy. The cheap thing worked at first – until I charged it. Then it broke, not the LED, not the LiPo management chip, but the controller itself!

ON BOTH FAKE LED LAMPS. Failure by design again.

I was contemplating converting these thing to full manual mode, i.e. bypassing the controller IC with the switch, but no time once again.

What I did manage to do was to test the LED. Here I’m bridging Vcc to the GATE of the MOSFET controlling the LED. It worked. BTW, it doesn’t have a LED driver OR sufficient resistor. The MOSFET itself was abused for that – and got quite TOASTY.

So, it ends here.

Two useless LED lamps that might be abused as annoyatrons. The LiPos don’t even have a protection circuit. Shees. I did order a decent replacement battery for one, but never used it. Guess what, no time.

Conclusion:

The real NiteCore LED lamps ARE WORTH EVERY CENT. They just work, no hassle, decent battery life …

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Tasty Durian

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Happy New Year 2019

Created with xscreensaver‘s “fireworkx”

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Forcing kdesu / xdg-su to honour ‘sudoers’

You can also just add this to $HOME/.config/kdesurc

Source from 2008 :-)

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VirtualBox mischief – getting rid of too many pesky users

This requires VirtualBox guest additions to be installed.

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A bit of VirtualBox scripting – NAT & DHCP

Maybe someone will find it useful…

Please note, as of today (2018-11-03) there appears to be an annoying issue with the DHCP server (5.2.20) for “NAT Network” (not just “NAT”). If you change the settings for the built-in DHCP server, you have to shut down any VM that is involved and delete the lease file (e.g. $HOME/.conf/Virtualbox/natnet1.leases).

If this is not done, the DHCP server will happily hand out old non-matching leases:

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Happy New Year 2018

Source

To Life!

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Sleep is vital

Bad sleep or poor quality will do you in.

Don’t go down that path.

LLAP

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Not So Half-Arsed Attempt At Aircraft Spotting — MUC Again

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SuSE museum — 7.3 to 9.1

SuSE Linux Professional 7.3

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2017

Real fireworks this time.

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A Ghost from 1995 – Good Riddance

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The worst Android tablet — Failed attempts of …

As You can see, there’s nothing of interest here. This post was cancelled due to lack of material & motivation. Please proceed to the next post in this mini-series. If you’re a user of headphones, you may want to turn down the volume a bit ;-)

In the meantime, you may find this scientific publication interesting:

“The unsuccessful self-treatment of a case of ‘writer’s block'”, J Appl Behav Anal., 1974, 7(3): 497, doi: 10.1901/jaba.1974.7-497a, [PDF][Original source]

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IWATSU LeCroy 9350A — bringing back old memories…

This “beauty” appeared on my desk today. Just testing & playing with it. I used the arb sig-gen of a PicoScope 2204A for generating a unpleasant test-signal. Trying to trigger on it was “interesting” :-)

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ERSA I-Con Nano — A pico review

Well… the device I got at work was a sad case of “dead on arrival”.

Temperature regulation was totally crazy, touching the case moved the measured value from about 350°C to 60°C, with a subsequent massive overshoot.

So we have to wait until the replacement unit arrives… maybe an XMAS present.

ersa-i-con-nano

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Attempted Aircraft Spotting — MUC

Since I hear the effing aircrafts all the time, I might as well go and take a closer look at them, no?

An impromptu Sunday trip to ‘MUC’ (or FJS).

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Relocating…

Still busy with stuff.

BUT, there is a functional dishwasher! What a great device !!!

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Triple Teardown Tardiness — Long Forgotten Boxes Of Stuff

Moving == carrying heavy boxes, lots of them.

Suboptimal.

Getting rid of stuff is imperative!

If You’re so inclined, You’ll find sloppy teardowns of 3 devices below. Mostly images and a bit of video footage at the end.

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“Six Sigma For Dummies” — An attempt of a book review

To make one thing clear, I was looking for a book describing the concept, methodology and application of “Six Sigma”. So you now know my expectations: facts, recipes, some math & statistics primer, NOT a lot of prosa / wall of text without content or just stating the blatantly obvious.

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The worst Android tablet — A quick teardown

Expectations.

When buying a cheap device, I don’t expect a display with “Retina” quality, but it should still be usable and not something the engineers who designed it have to be ashamed about. It shouldn’t be a piece of shit (in this case it wasn’t). The same goes for all other parts. I can live with less memory, but it should not be defective. If a device claims “Quad Core” I expect it to be reasonably snappy and not turn into a hibernating grizzly every 5 minutes. Cheap devices require trade-offs, but general usability should not be among that.

20160313_162051

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