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Debian Linux on a GPD Win

2018-01-05 22:09:17,  In: Linux, Debian

OK, so I bought a GPD Win. Small, Intel-powered computer with 4GB of RAM, Atom processor (2-core, 4-thread?) and 64GB of SSD. Unfortunately, with Windows 10 by default.
Because I found Windows 10 unbearable even when following the manuals to optimize and make it smaller, I decided to try with Debian.
Unfortunately this device is a completely closed UEFI machine so it doesn't allow much modification. However, I found Debian USB sticks, when not touched, bootable.
This is a set of notes which are based on Hans De Goede's blog entry about installing Fedora on GPD Win.

   What will be needed

Installation of Linux on GPD Win is quite specific and different than typical Debian installation. Many drivers for things like Wi-fi or sound chip are absent, improperly installed or misconfigured so it's needed to patch the system up. To do it, you need
- A GPD Win
- A 4GB USB stick or bigger
- USB hub. The faster the better.
- USB wi-fi adapter...

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About PC power supply units

2017-11-21 10:26:00,  In: Electronics, Curiosities, Other

Recently I acquired a few power supply units for PCs and I decided to share some knowledge about their quality. Because these units were defective I had to open them, fix if possible, and re-solder wires as they were from some e-junk wjere copper is valuable. Testing was simple: Load the power supply unit with an old, damaged IDE hard disk, turn it on, check voltages (they should not be well OK, as one old hard disk is not enough to keep regulated line), then load the unit on 5V line with 12V/21W light bulb and check regulation then. Most passed these tests after capacitor repairs.

   Tagan TG380-U01

Let's see the first example: The Tagan TG380-U01. Tagan is known as manufacturer of a good, high-end power supply units, and it looks like they made them really well. The unit is packed with technology, they put large heatsinks and thermal regulator on a separate, small board. Because packing is tight, two fans are pumping air through the unit.

Here is an example how the good power supply unit...

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Re-making a gear for tape memory

2017-09-24 01:47:52,  In: DIY, Electronics

A long time ago I acquired a microcomputer-grade tape recorder produced by Polish factory: MK-450. The problem with this device and a few other tape drives (like Mera one for large cassettes) and even consumer-grade decks (MK-250) was a poor quality of its gears prone to breakage. Usually, during seeking or playback, a loud crack is heard and tape is pulled into recorder or forward seeking stops working while motor is still heard. Recently I got a possibility to print something with 3D printer, so I decided to experiment with it. In this post I'll show how to re-produce the existing, physical gear into computer model. To quickly show things, the result is nice:

   But... why does it fail?

The plastic used to make these two specific gears (in MK450) is different than polymer used in other gears. It degrades into white, crumbling powder with atmospheric contact and probably...

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Installing adNauseam on PaleMoon and the new malware problem

2017-09-02 13:30:12,  In: Hack, Other

Recently PaleMoon developer decided to blacklist adNauseam extension, so here is a quick method of re-enabling it:
1. Go to about:config
2. Set extensions.blocklist.level to 3.
3. Install addon, go to Tools -> Extensions and turn it on there. Remember that it takes the function of adblocker so will collide with most Adblocks.
4. Watch your addons as this may allow to install uncertain ones in the future (currently only adNauseam has this level). If you want to know, the list is online-updated and is maintained in blocklist.xml in your profile directory. Configuring adNauseam, if your workflow involves visiting only a set of trusted sites you should turn on exception for non-tracking ads.
And small explanation what is it.
The add-on fights with unfair malware-delivering companies (today re-defined as "advertisement") by hitting their collaborators - website authors. Then, according to ideology called "free market", authors should change malware...

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Curiosities: Inside a lab-grade power supply from 1970s

2017-08-22 01:17:11,  In: Electronics, Curiosities

Some time ago I was looking for an used adjustable power supply unit. Finally I had a possibility to purchase a 300W adjustable (0.1-30V, 10A max) power supply unit for a relatively lower price. The only thing about it was that it was a unit from early 1970s, transformer-based, 25kg of hardware. I finally got it, brought home and decided to restore it.

It is a ZTR-1/71 power suply unit made by Inco in Poland. In 70s and 80s, Inco (Full name: Zaklad Produkcyjny Aparatury Elektronicznej INCO) was known manufacturer of measurement devices, lab equipment and all "special" production e.g. for military, intelligence or security offices (also devices for communication, location of radio stations or radar applications), so I expected quite interesting things inside. It is still possible to get their old catalog on Silesian...

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Memory usage of different desktops in Linux (UPDATE: 32-bit)

2017-08-02 14:02:11,  In: Linux, Debian

While installing Linux on older machines a very popular question is "What desktop environment should I use?". With older machines, usually the biggest bottleneck is not a CPU, but RAM. Too small memory causes swapping, and it slows Linux even more. On the other hand, more free RAM makes system run faster. I decided to install Debian 9 (Jessie) in different configurations to measure memory usage of different desktop environments. All measures have been made on stock installation offered by Debian installer, by installing on virtual machine.

   Linux and memory

There is a large difference between memory reported by "free" and "htop" programs. It is coming from the method of using memory in Linux. The main rule here is that unused memory is wasted memory, so Linux uses free memory for buffers and caches, making system faster. While "free" shows buffers and caches memory as used, htop doesn't, only shows buffers on memory usage bar in blue/green color, while number indicator shows amount of RAM actually...

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Eee PC 900 as ultra-portable computer

2017-05-03 17:38:06,  In: Linux, Debian, Retrocomputing

Few weeks ago I bought a damaged Asus Eee PC, model with widescreen and Celeron processor. These computers were sold about 10 years ago as "netbooks", which were a transition between notebooks and tablets, when companies were not so sure that they will force users only to consume ad-filled "content" from the Internet. The computer has been repaired and now it works. I decided to make some use of it. Let's look what is inside:
- Intel Celeron processor at 900MHz
- 1GB of RAM in DDR2 SODIMM stick
- 4GB on-board SSD disk
- 16GB SSD disk using proprietary connector.
- Wi-fi, sound, Intel GMA950 video card, SD card reader and battery - all which modern laptop should have.



Previously, the computer had Windows XP installed, in its Home edition. There is a sticker for it so someone bought a license. Unfortunately, even fresh install of Windows XP on this machine works terribly, it is slow, overuses hard disk and suffers of few-second freezes. I decided to go with Linux as these...

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LibreOffice base: One macro to open them all

2017-04-22 15:39:42,  In: Hack, Database

Recently I was developing a simple database application in LibreOffice Base version 4.x. This is quite slow tool, but with a few modifications and tricks complex applications can be made.
Usually, database application consists of several forms supporting several tables opened from each other or common "switchboard" form. The problem in LibreOffice base is that it is not possible to easily make the "switchboard" form with buttons launching forms for other tables. There is no "macro wizard" to make it easily and most existing databases use extensions or hard-coded macros for it.
Officially, the only way to do it is by using Switchboard extension which is not much supported in later versions. Another way is to create macros for buttons. If you have 10 buttons opening 10 forms, you will have to make 10 macros connected to them, opening different forms. As in pure Open-Source programs, the only documentation is source code. Let's do it in more universal way: I inserted a target form name in ToolTip...

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Weak passwords and weak resources

2017-03-14 20:04:31,  In: Security, Other

In the last few years, questions about password complexity emerged from time to time. There are list of common passwords, they are counted in leaked daabases, in hashed and unhashed forms. Blog entries are usually alarming about the poor complexity and length of passwords. Recently, a Password rules are bullshit post on Coding Horror blog shows how password rules are bad idea. However, they seem to be insecure in totally ignored mechanism having nothing to do with their length.

To illustrate this problem, let me tell a story about graphics card drivers. In 1997, to download a new driver to my video card, I could do the following thing:
1. Go to my card manufacturer's website
2. Click Support, then Downloads
3. Connect to FTP in "pub/drivers" directory, or select board from the list
4. Download driver for my OS. Mission accomplished, driver in my disk.

20 years later:
1. Go to my...

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A hole in the casing

2017-01-30 20:50:00,  In: DIY, Retrocomputing

Sometimes old computers come with broken plastic parts. When only cracks are present, it's easy - we can fix them with glue or staples melted into plastic using soldering iron. Even totally broken casing can be fixed this way. The bigger problem is when the casing lacks some part which cracked off. Recently I purchased an old computer with broken front panel. From photos it can be seen that damages aren't so big and two parts can be glued together, but if you look closer you will notice that a whole bottom-left corner of panel is missing. How to fix it?


I decided to try with hot-melt glue applied from pistol-type hot glue applicator. First, I found that front panel is made of porous, well-glueable plastic, so I glued broken parts together using cyanoacrylic glue. I found that this panel is painted with something similar to white acrylic paint. Next, I started to apply hot-melt glue to form a patch. The key factor here is temperature. The glue comes from the gun very hot. When hot, the glue is liquid...

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