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Top Articles!

AVR SDCard FAT support with FatFS | 19633 Views | Rate 38.88
AVR SDCard FAT support with FatFS
Single Chip Computer | 1870 Views | Rate 29.22
Single Chip Computer
3V to 400V regulated inverter for Geiger counters | 2914 Views | Rate 18.8
3V to 400V regulated inverter for Geiger counters
Virtualmin Git return code 22 fatal: git-http-push failed | 113 Views | Rate 14.13
Virtualmin Git return code 22 fatal: git-http-push failed


News & Updates

2014-12-12, Virtualmin Git return code 22 fatal: git-http-push failed

2014-11-25, Electric Fence - 20KV pulses for perimeter defense

2014-10-29, Statie de monitorizare a radiatiei de fond in Timisoara

2014-10-29, uRADMonitor - Online Radiation monitoring station


Virtualmin Git return code 22 fatal: git-http-push failed


Installing GIT from Virtualmin is easy. You just need to go to Edit Server->Enabled features->Allow Git Repositories Create a repo by going to Services->Git repositories: Then go to Edit Users->select a user->Other user permissions and grant them access to your new repo: You are now ready to add your local code to the new repo: […]

Single Chip Computer


Learn how to create a single chip computer running BASIC.

3V to 400V regulated inverter for Geiger counters


A robust regulated high voltage supply, an inverter (boost converter / step-up) 3V to 400V for portable applications.

Android Open Source Audio player using MediaCodec API


An open source android library project implementing a versatile audio player that supports the most used audio formats Mp3, AAC, Vorbis, WMA and more.

Google Tango Hackathon in Timisoara


Some impressions on the Google Tango Hackathon held in Timisoara in April 2014. See one of the Winner projects, the Camera 3D and some insight on the new device from Google.

Electric Fence Circuit for perimeter protection


Two battery operated, portable, electric fence designs using 555 and 556 timers.

Infused™ project


Infused™ is about passion for design, music, digital, programming and alternative culture in Timisoara, Romania. Structured as a set of interviews with people involved in the act of creation regardless of its final form, the first video covered Flat UI & Minimalism, featuring Madalin Gageanu and Adonis Raduca: I was excited to get an invitation […]

Small size High-Voltage regulated inverter


Build a battery operated, compact high voltage inverter for Nixie tubes, neon bulbs or Geiger counters.

Discussing security in online on TV News show


As an IT specialist, I’ve been invited to a TV Show where I had the chance to discuss a few details on Internet and computer usage safety best Practices, a covering a little on security topics: The discussion is in Romanian.

555 Timer revisited


An article on the well known 555 timer and a few rather unknown applications.

Complex Android GridView with Drag and Drop functionality


A tutorial on how to add Drag and Drop functionality to a gridview control.

Simple Gridview Control for Android


Build a custom gridview control for Android, programmatically.

DIY Geiger Dosimeter with external tubes SBM-20 and SI-29BG


An open source digital portable radiation dosimeter, with external connector for attaching various geiger tubes.

Tube: SI-29BG (CИ-29БГ) Sensitive Small Geiger Muller


Got a few SI-29BG tubes for my ongoing uRADMonitor project. Smaller, yet more sensitive than the SBM-20. While testing them, I found one that is DOA.

CCD Radiation detectors


Mobile devices with embedded cameras can be used to detect x-rays.

Software security in Shareware


Applications released as unlockable trial versions are vulnerable. Learn how to protect your work by embedding bulletproof security techniques.

Custom Rotary Knob Control for Android


A custom control for Android that can be used to adjust the volume and to toggle between on/off state at the same time.

The MQ-9B Combustible gas sensor


A quick test with the combustible gas sensor, MQ-9B and an atmega8 microcontroller.

Using a Rain sensor with AVR Microcontrollers


A simple rain sensor connected to an ATMega8, provides readings on the level of water detected on its surface.

Tube: SI-12B (CИ-12Б) Mini Pancake Geiger Muller


The SI12B is a mica window compact Geiger tube, designed for measurement of alpha and soft beta-radiation.

Tube: SBM-20 (СБМ-20) Geiger tube


Medium size sensitive Geiger tube for hard beta and gamma radiation.

Implement Photoshop-like Curves with Leptonica


If you’ve used Leptonica, you probably know it’s a great library, but when you want to use it to replicate Photoshop like effects, you will quickly get to want more than what the library provides by default. Take the pixGammaTRC primitive as an example: If you want to modify the lightness of your image, (making […]

Enhance saturation in images programatically


Increasing the saturation in an image is equivalent to increasing the “amount of color”, while a completely desaturated image would be a grayscale image. See the images below: Normal Saturated Desaturated Grayscale Logic and Implementation Algorithm The images are composed of pixels. For a RGB24 image, each pixel is a set of 3 bytes, 1 […]

UT50 NaI Scintillation probe


I met some great people today, and I also got a wonderful device for my ongoing experiments as a gift: The UT50 Scintillation probe, manufactured by SC ICPM SA Romania. It features a huge NaI(TL) crystal, with a diameter of 5.5cm and 5.5cm length. The photomultiplier is a British EMI9656KB and the entire device is […]

AVR SDCard FAT support with FatFS


You’ve probably seen or done lots of cool microcontroller projects already, but did you ever consider adding permanent data storage to your projects? I did, and there are numerous advantages: saving data from sensors (data logger), saving configuration files, reading external content like images or songs, and so on! One thing is to connect an […]

Using FS1000A/XY-FST RF Radio module with AVRs


Wireless data transfer can be useful for a variety of projects. I stumbled upon a very low cost emitter+receiver modules pair, and planned to use it for some time now. There are a few variants available on the market, but they do quite the same thing, just the operating frequency might be different (315MHz / […]

Blackberry 10 Command line development


Build, compile, sign and deploy applications for the Blackberry Z10, using only the command line tools.

SSH to the Blackberry Z10 (BB10) Guide


A step by step guide on how to generate RSA keys and then use them to establish a SSH connection to a remote Blackberry Z10 device.

Global radiation monitoring network


EDIT: there is a dedicated blog on this project, here. Make sure to follow it for latest news. A few days ago I announced my intention of creating my first crowd-funded project, but I didn’t tell you what was it about. Well, I’m planning quite a challenging project – to bring my uRADMonitor to a […]

First Kickstarter project is closing in!


Preparing for my first Kickstarter project . Let’s make it happen!

Leptonica saturation deficit workaround


While working with Leptonica I had the unpleasant surprise to notice that the saturation function pixModifySaturation was not really working properly (or at least not entirely as expected). First I didn’t even know what was wrong, I just felt it didn’t look right, then I saw that by transforming the saturation in Leptonica with pixModifySaturation […]

Tube: VA-Z431 Geiger tube


VA-Z431 test tube shaped geiger muller tube for liquids.

Cartoon yourself using Leptonica


Showing how to create a cartoon effect using the image processing library Leptonica

A 3D Carousel View for Android


Create a beautiful custom 3D carousel view, to give your Android user interfaces a modern look. Sample code included under GPL v2.

Android tiled background


Learn how to create a simple tiled background for Android applications using Java code.

Tube: 258-B Amperex rectifier


The Amperex 258-B is a half-wave Mercury-Vapor rectifier tube used in power supplies.

Tube: GP-5 (ГП-5)


The Svetlana GP-5 (ГП-5) is a glass-envelope beam power triode intended for use as a shunt regulator or pulse modulator in high-voltage systems.

Coil Winding machine counter with Atmega8 and Reed relay


A digital counter with a nice LCD display that supports both incrementing and decrementing. Good for various purposes, in this case as a display to a coil winding machine.

Developing for Blackberry 10


A short insight on how to get started with developing for the new Blackberry 10, using dynamically created controls.

Victoreen CDV-717 Remote Gamma Survey dosimeter


The CDV-717 is a very high-range gamma radiation ionization chamber detecting instrument, manufactured by Victoreen back in 1964.

CDV-742 Dosimeter and CDV-750 Dosimeter Charger


The CDV-750-5b Dosimeter Charger is a self contained battery-operated instrument.

Repairing a Victoreen CDV-700 6B Dosimeter


Fixing a CDV700 dosimeter can be difficult because original replacement components are not an easy find.

Tube: 1B40


External Cavity tube, 1KW at 1075 to 1096MHz.

Tube: USN-5J29


5J29 is a split anode magnetron. This device is water cooled, the water flowing round the metal loop.

How to make metallic sodium


Electrolysis of molten sodium hydroxide at 318 °C .

How to scale an Android UI on multiple screens


Learn how to scale an user interface to maintain the same aspect ratio, while running the same code on various Android devices.

Atmega8 and Nokia 5110 LCD


A C++ Library for AVR microcontrollers that allows easy connectivity to the Nokia 3110/5110 graphical LCDs.

Detecting an ultrasonic beacon


How to build an ultrasound beacon and the corresponding receiver.

Virtual Reality App Controls Real household objects


You can use your smartphone (android/iphone) to control electrical equipment inside your home. See how.

Dual H-Bridge for controlling two motors


Build a dual H-bridge board to control two motors.

How to set the AVR Fusebits


Learn how to set your atmega to work with various external crystals, program the fusebits, and build a fusebit doctor to revive your AVRs, in case you wrote the wrong settings .

NMEA GPS Library for AVR Microcontrollers


An open source library that allows you to use a NMEA GPS Module with an AVR Microcontroller. UART Communication and NMEA Parser is included.

ATMega128 and HD44780 LCD using 3 Wires with the 74HC164


Learn how to transform your HD44780 LCD into a easy to use, serial LCD, that you can connect to your microcontroller using only 3 wires! It’s time to save a few pins, and expand your project’s functionality!

The Hyacinth – a timelapse video


A timelapse video of a Hyacinth opening into flower!

Microscope photos: White and Blue Mold


White and blue mold as seen under the microscope, magnified up to 1000 (one thousand) times!

Building a robot – Make the robot follow you


Building an autonomous robot using a rover platform and advanced electronics is not an easy job. Kevin asked me to build a robot that would follow its user. A companion, very much like a robo-dog. See the project log here.

uRADMonitor – Unusual Background Radiation Reports – Explained


This page has been created to report unusual activity (radiation, temperature, humidity, luminosity, barometric pressure), as recorded by the uRADMonitor, including all the debug data to support the results. I cannot guarantee the measurement precision, I merely present the data recorded by the instruments.

Programmatically Injecting Events on Android – Part 2


A JNI Library for Android, to inject keys and touches but also listen for incoming input events to and from all applications, available as Open Source under GPL.

Top 10 Radioactive Electronic Tubes


Some of these tubes contain small quantities of Cesium-137, Cobalt-60, Radium-226, Krypton-85. The radioactive elements have been added to increase the electronic response by improving the internal ionization processes.

Digital Soldering station ZD937


A short review on my new Christmas gift, a neat digital soldering station, ZD 937, and a quick light installation that I did with LEDS, running directly on mains , 220V, using the ZD937.

DIY/Homemade Radiation Geiger Dosimeter


A digital dosimeter design that can be used with multiple geiger tubes, constructed around the atmega8 microcontroller and a 2×16 LCD. Equipped with a radio Bluetooth module for remote operation.

BMP085 Barometric pressure sensor


The BMP085 is a compact, low power sensor for reading temperature, barometric pressure and altitude. See it in use with Atmel microprocessors.

Temperature and Humidity sensor DHT-22


DHT-22 is a small size, compact, dual temperature and humidity sensor featuring one-wire connectivity.

HC-SR04 Sonar with Atmega8 microcontroller


Build an ultrasonic sonar for non-contact distance measurements, using an Atmega8 and a HC-SR04

Statie de monitorizare a radiatiei de fond in Timisoara


Locuiesc in Timisoara, si de curand am terminat o statie de monitorizare a nivelului de radiatii de fond. Cu exceptia catorva institute din tara, care rar dau publice graficele, statia mea e probabil singura alternativa de acest gen, accesibila utilizatorului obisnuit. Acest articol, redactat in romana, prezinta detalii asupra statiei, explica ce este radiatia de fond si cum apare ea, dar si ilustreaza grafice in timp real.

uRADMonitor – Online Radiation monitoring station


I’ve developed the uRADMonitor as an Environmental Radiation Surveillance automated monitoring device. Data is gathered in real time, 24/7, and is exported via the Internet to a database online. The data is available in customizable charts for analysis.

DIY/Homemade Geiger Muller Digital Counter V3


A story of making a DIY Digital Geiger counter circuit, that can be used with several tubes. Add an enc28j60 Ethernet module and use the data to create graphs available online!

Temperature Sensors DS18B20 and DHT11 with Atmega8


Use the Atmega8 with two temperature sensors: the DS18B20 and the DHT-11. The latter also offers relative humidity data.

Vacuum tube tesla coil (VTTC) using Russian GU-81m


Vasil sent me 3 of his complete tesla coil systems. So here I am rebuilding his GU81m VTTC.

Tube: G21-H Geiger Muller


A Geiger Muller tube for Gamma radiation.

Tube: UX-6653


A TR Switch tube used in Radar technology, manufactured by Raytheon.

Tube: EMI9524


A sensitive photomultiplier tube, used in scintillation detectors.

Tube: ZV1009


A klystron capable of up to 6000MHz

Bausch and Lomb Microscope


Read a post on my new acquisition, a Bauch&Lomb compound binocular microscope, a high quality tool, put to some good use to capture a few micro photographs. It can get up to 1000X with its current optics.

Atmega8 and enc28J60 for ethernet support


Learn how to create a network interface for your microcontroller projects. Here I have shown an example using the Atmega8 and the enc28j60 . Build a simple Webserver to show sensor data such as temperature or humidity.

Android Overlay Mouse Cursor


Learn how to create a mouse cursor in Android OS programatically, using Overlay Views.

Android default orientation and orientation change events


Find the default orientation on Android devices, and intercept orientation changes even for activities locked in portrait or landscape mode.

Bluetooth and iOS – Use Bluetooth in your iPhone apps


Learn how to use the BluetoothManager private APIs on iOS / iPhone/ iPod to discover nearby connections, populate a list view with the results, and try to establish a Bluetooth connection to the remote devices.

Developing for Apple iOS


A short guide to get started with iOS development. How to build a simple list view.

Capacitor Discharge Microspot Welder / Cutter


A DIY microspot soldering/welding/cutting device using energy stored in a very large capacitor delivered as precisely calculated pulses to working electrodes.

Mac mini is big enough to blow a full size PC away


A short review on a Mac Mini that I recently acquired. I plan to use it as my new fixed workstation instead of my older P4 PC.

Atten ADS1102CAL Oscilloscope


For my first oscilloscope, I opted for the Atten ADS1102CAL. A few months after, I could say I’m extremely happy choosing this robust device, that does an excellent job on my workbench.

Projection keyboard


The laser keyboards use laser and infra-red technology to create the virtual keyboard and to project the hologram of a keyboard on a flat surface.

Anoto Bluetooth Digital Pen on Android OS


A digital pen solution for Android OS.

USBAsp – AVR USB Programmer


A good source for cheap AVR USB Programmers. USBasp modules.

Simple Switched power Supplies


Several simple SMPS designs, constructed by Daniel, @danyk.wz.cz . A great resource to learn about various SMPS topologies.

Programmatically Injecting Events on Android – Part 1


Three possible solutions for injecting events (both keys or touch events) in Android.

Canon S2 IS CCD Repair and IR Mod


A quick CCD replacement for my Canon S2 IS camera. CCD IR filter removed to enable IR photography options.

AVR Studio 5 snprintf / vsnprintf problem with Floats


How to fix the problem with Float variables in AVR Studio

Tube: IVL1-8/13 (ИВЛ1-8/13)


The device consists of a hot cathode (filaments), anodes (phosphor) and grids encased in a glass envelope under a high vacuum condition. The cathode is made up of fine tungsten wires, coated by alkaline earth metal oxides, which emit electrons when heated by an electric current.

Tube: SBT-10A (CБT-10A)


SBT-10A, a rare geiger muller tube for professional equipment.

AVR Studio 5 C++ Support


Build C++ projects with AVR Studio 5

BlackBerry Splash Screen


A tutorial with code that presents an easy way to show a splash screen in your Blackberry application. Show the first Splash-Screen, wait a few miliseconds, than load the rest of your application.

Developing for Blackberry -part 2-


An updated article on some very basic first steps with Blackberry programming. Tools, sample app, and how to get it running.

DIY/Homemade Geiger Muller Clicker V2


This geiger counter circuit features a regulated high voltage supply, with adjustable output. It can run on a single AA battery (1.5V)

Digital Counter using CD4026


A digital counter using CD4026 for fast event counting as those from Geiger Muller tubes or scintillation probes.

Melting lead


Melting lead at 327.46 °C to recycle it as ingots.

Tube: MR-04


MR-04 is a ionization tube.

Longitudinal Excitation Nitrogen Laser


A Longitudinal Excitation Nitrogen Laser design, using a fridge pump for vacuum and N2 from air as lasing medium.

Android 4.0 (Ice Cream Sandwich) Emulator How-to


A quick guide on how to configure an Android 4.0 Emulator image.

Tube: VA-Z320


VA-Z320 mica window geiger muller tube

Tube: MCT-17/SI-3B (си-3Б)


MCT-17 Mica Window Geiger Muller Tube

Tube: SBM-19 (СБМ-19 )


SBM-19 Geiger Muller Tube

Android BluetoothClass Major Service Classes, Minor and Major Device Classes


Learn how to get over some limitations in Android Bluetooth SDK to read the Bluetooth COD (Major, minor classes) for a given Bluetooth device.

Android getSharedPreferences NullPointerException


Avoid the NullPointerException error when using the getSharedPreferences on Android.

Auto Start Android Service on Boot


Learn how to make an autostartable service on Android OS, using the BOOT_COMPLETED notification.

Building a socket for a power tube – TGI2 400/16


How to build a socket for a big Russian hydrogen Thyratron tube using copper connectors made out of a pipe.

Thyratron Switched Tesla coil (THYTC)


Using a hydrogen Thyratron tube to switch a Tesla Coil. The Thyratron tube replaces the noisy spark gap.

Relaxation oscillator using a Hydrogen Thyratron


Some details on the relaxation oscillators and my implementation using a hydrogen thyratron.

Pulse generator (Variable duration, frequency and amplitude)


A very customizable pulse generator built using three 555 timers, to control a relaxation oscillator hydrogen thyratron.

Pulse forming network


My DIY PFN for a relaxation oscillator using a hydrogen thyratron.

Twin Marx Generator


Some pictures with my marx generator throwing high voltage discharges!

Tube: TGI2 400/16 (ТГИ2-400/16), Russian hydrogen thyratron


A hydrogen thyratron is a device capable of switching big amounts of energy. The major advantage over other thyratrons is that the deionization time is reduced by using the hydrogen gas, generated in a small reservoir inside the tube, from a metallic Hydride.

Battery powered high voltage multiplier for gas igniter or stun gun


Learn how to build a compact gas igniter or stun gun, powered by a 9V battery.

Electric Fence – 20KV pulses for perimeter defense


Protect your tent’s perimeter from bears, when in the wild. A 20KV pulse generator will inflict painful shocks to anyone touching the perimeter electric fence wire. Not lethal, but very painful, enough to put unwanted visitors on the run.

Small Spark Gap Tesla coil (SGTC) #4


A small spark gap tesla coil, a good example for an relaxation oscillator.

Rewind a Microwave Oven Transformer


How to rewind a MOT transformer for a high current low voltage power supply.

How to list symbols in a .so file


A simple way to extract the symbols in .so files.

Android “Unable to open sync connection” error


How to fix the Unable to open sync connection, displayed in Eclipse Console by Android SDK tools.

Wireless Power Transmitter


A wireless power transmitter used to send electrical energy without wires. It uses induction, an emitter and a receiver working on the 63.1KHz frequency.

Electronic Ballast for fluorescent lamps


A simple electronic ballast running on 220V designed to work with up to four small power fluorescent lamps

Vacuum tube tesla coil (VTTC) using Russian GI-30


A vacuum tube tesla coil built around the Russian tetrode GI-30. My first VTTC and my first vacuum tube circuit, and some very rewarding results.

Removing a stuck filter from a lens


An easy way to remove a stuck filter from a lens. All you need is a piece of flexible PVC insulated wire.

Fukushima plant time lapse video March


A timelapse video of the Geothermal power plant in Yanaizu-Nishiyama, Fukushima . Daylight time in 4 minutes.

How to give an image an old photo look


A simple way to give to an image an old photo look using actions in Photoshop

How to make a curvy selection in Photoshop


Create a proper selection using a pen tool in Photoshop

High Voltage Power supply – 140KV


A CW High voltage supply that produces up to 140000 volts (140KV) . Simple, clean design, without oil, but with high quality multipliers.

Homemade Flyback secondary -3-


Build a disc shaped flyback secondary. A robust new design, that will do a great job in your High Voltage projects.

DIY/Homemade Geiger Muller Clicker V1


An article presenting a simple DIY Geiger Muller counter using the Russian tube SI-22G and a single transistor regulated inverter that puts out 400V, as required by the tube. A very basic detector assembled in 5 minutes. See an operation comparison to the Radex RD1706.

Android overriding Menu key to disable keyboard popup


The standard functionality on Android devices makes the software keyboard popup every time the Menu is long pressed. This may be annoying or unwanted. Here’s how to disable it.

Android 9 Patch images for custom controls


Design custom shaped corners Edittexts or TextViews, or any other kind of Android interface controls, using 9 patch images that keep their aspect when stretched.

Android Contacts – a simple Contact Selector


The Android Contacts tutorial part 5, here I show a robust solution for selecting a contact from a list. A filter/search mechanism is also implemented using the SimpleCursorAdapter.

Android Contacts – Searching for contacts


Part 4 of Android Contacts tutorial presents an easy way to programatically search and retrieve a contact and all the fields we are interested in such as Phone, Email, Web, Company, Address, etc.

Android Contacts – Invoke the Edit Contact Intent


In Android Contacts tutorial part 3, I present a simple way of opening a contact in the System contact form using the ACTION_EDIT Intent .

Android Contacts – Custom Contact column to get the LOOKUPKEY


Part 2 of the Android Contacts tutorial, showing how to add a custom column to a contact, and how to use that to identify a newly added contact and read its LOOKUPKEY.

Android Contacts – Add a new Contact using ContentProvider


Part 1 of a tutorial on working with Android Contacts: add a new contact programatically, including name, email, company, phone but also a thumbnail contact image .

How to fix wash out photos from airplane


A simple way to fix the wash out photos from airplane using Photoshop.

Android WebBrowser using WebView


A few easy steps for an Internet Web Browser for Android. Learn how to use a Webview, load pages, inject Javascript, read the HTML source code and more.

Android GUI with Header+Scrollable Content+Footer


Create an Android GUI with Header, middle scrollable content, and a footer.



An article on Thyratrons and a film showing three energized tubes : the 714, the 309/FG17 and the ELC1B.

Simple DIY Induction heater


A Royer oscillator with 2 IRF540 N-Channel mosfets, a 0.47uF Capacitor and a 1500uH inductor used for an induction heater. The mosfets remain cool, even with such small heatsinks.

Android PhotoPicker using Intents and Gallery


Learn how to Invoke the Android Gallery Intent to pick a photo and get the path in your application. This photo picker returns the image path directly in your application.

Android Custom Complex Listview with Header (no XML)


Create a dynamic (no XML) listview with header with all the bells and whistles. Learn how to use the item position to change its background and content for a complex result.

Android Unique Device ID


Learn to read an unique device ID from your Android phone or tablet. Use the ID to generate software security keys or for cryptography applications.

Developing for Android – the SDK – update 2011


Get started with Android Java development – a tutorial with detailed steps and lots of pictures to help you make your first android application. Use Eclipse and the Android SDK.

A Farnsworth–Hirsch Fusor failed attempt


My first attempt in building an inertial electrostatic confinement device . It didn’t work.

Android Vertical TextView / Custom Angle Text


Learn how to create a Custom TextView class that can draw vertical text or rotate the text to any given angle. Easy!

Multitester using ATMega8 and HD44780 LCD


An Atmega8 multimeter that can measure Transistors: Bipolar/Mosfet , Diodes and Double Diodes , Resistors, Capacitors: between 0.2nF to 7300μF, Triacs and Thyristors.

Ion thruster using 50KV Supply


Build a Ion Thruster using light materials and power it using a 50KV supply to see another kind of propulsion.

Homemade/DIY High voltage probe


Using a high voltage 1GOhm resistor to built a DIY high voltage probe, to measure voltages up to 55KV with a normal multimeter, by scaling the voltage down by 1/1000.

X-ray intensifying screen


Get X-ray intensifying/fluorescent screens from X-ray cassettes used for radiography.

NaI Scintillation Probe and Gamma Spectroscopy


A scintillation probe enclosing the regulated high voltage supply, the signal amplifier, the photomultiplier and the scintillation crystal (NaI). Building a DIY counter for a NaI Scintillation probe. AtMega8 and a bluetooth module for wireless data output. A cheap and easy to build homemade dosimeter with applications in spectroscopy.

High Current Invertor using ZVS


Use a ZVS Driver as an invertor for a high current supply.

We’ve got a new design!


The new PocketMagic.net logo and layout

Marx Generator 200KV discharge – artificial lightning


See a 200.000 Marx generator in action. 20cm discharges!



You can boot an Android image, from the SDCard of an Windows Mobile HTC HD2 Pocket PC, using Haret. Be careful to use a 2GB max SDCard!

High Voltage Power supply – 50KV


My homemade high voltage power supply that can provide aprox. 50KV for 12V in.

Android NDK Cygwin make error 127


Android NDK Cygwin make error 127, but only on some computers. I suspect there’s a conflict with other development tools (based on PATH, etc).

Android Native Play Sound using /dev/msm_pcm_out


Directly interface the PCM device, using low level native C programming. Play sounds by sending data to /dev/msm_pcm_out

Android Native Screen capture application using the Framebuffer


Learn how to do a programmatic screen capture on Android, using the framebuffer and some native C code. See how to correctly save a BMP file.

Android C native development using the NDK under Windows


Learn how to compile your C code to native Android executables, using Windows, Cygwin and the Android NDK in just 3 easy steps.

Lenovo ReadyCom5 and WLAN AP Issues


Lenovo ReadyCom 5 can cause a wireless router to self-reboot, remotely.

Reinstalling Vending.apk (Market) on Android


Learn how to reinstall the Market application on your Android, using the Vending.apk installer.

Android Bluetooth controlled robot – Part 1


Learn to connect a bluetooth module to an ATMega micro controller via the UART serial interface and even further, discover it using a bluetooth enabled Android phone. The 9600bps serial link established, can than be used to exchange data: read sensors or control the robot.

High Voltage Multiplier (Half Wave Villard Cascade) 28 STAGES!


Build a Half Wave Villard Cascade of 28 Stages. That means for 10KV in you get (in theory) 280KV out! An incredible voltage, perfect for physics experiments.

Tube: EM-11 (6U5G) Magic Eye tube (tunning tube)


EM-11 is a magic eye tube, used in old radios for tunning. See some schematics on how to use this tube, for some green, fluorescent effects!

Android Dynamic (no xml) Custom Adapter Listview


A tutorial on how to build a custom adapter for an Android Listview control, and how to catch the onClick event correctly.
Includes source code.

Android NDK for Windows setup guide


See how to configure Android NDK with Windows and build your JNI project in a few easy steps.

Webcam Surveillance with motion detection algorithm


A homemade/DIY security system using a webcam, a low power server and a surveillance software.

WinCE Broadcom stack FindAttribute SDP_DISC_ATTTR_VAL 256Bytes limit


See the real limit for receiving a SDP bluetooth device attribute in the SDP_DISC_ATTTR_VAL structure for the Broadcom Bluetooth Stack.

Kvarts DRSB-01 Dosimeter


The DRSB-01 is a simple Geiger Counter device that can be used to detect normal vs. dangerous levels of ionizing radiation (gamma and beta).

Apache won’t start – Skype to blame!


Skype opens the TCP port 80 for unknown purposes. It doesn’t ask for user’s permission. This “feature” however creates problems when running legitimate software like an apache server. Think twice when installing “bells and whistles” software like Skype, Messengers, and others.

Homemade mini-itx server


See how to build a case for a mini-itx computer board. A lot of processing power in a tiny box.

Peltier thermo-electric cooler


Use a Peltier cooler and electricity of pump heat and freeze water.

WinCE Bluetooth Broadcom stack ‘Not a valid Pocket PC application’ Error


Some details on the ‘Not a valid Pocket PC application’ error resulting from calling the IsStackServerUp API in Windows Mobile Bluetooth Broadcom stack applications.

Victoreen CDV-700 6B Dosimeter Mod (Audio/BNC Connector)


The CDV700 dosimeter variant 6B (newer) and a few mods to improve functionality: audio connector and bnc connector.

Tube: SI-14B (CИ-14Б) Pancake Geiger Muller


A highly sensitive pancake geiger muller tube, the Russian CI14B/SI14B

Radex RD1706 dosimeter


A short review on the Radex RD1706 dosimeter, how good it is, and how can it be compared to other dosimeters, eg. the Terra-P MKS-05.

Homemade Flyback secondary -2-


Build your own indestructible flyback secondary

Resizing Linux partition results in GRUB Error 17 fix


See how to fix Grub Error 17 on Ubuntu.

Variable 0..30V Regulated Power supply for 20A max


A variable 0..30V power supply for max 20ampers! See how to handle all the power and build your own reliable lab power supply.

Marx generator


My first marx generator that gives 5cm sparks.
EDIT: >20cm sparks!!!

Android dynamic TAB Control


Learn to create a tab control on Android, without the XML layout. Add an image to the tab control in a few easy steps.

Linear Pseudorandom number generator (PRNG)


Understand what a random number is , how important the chaos is, and how to understand a sequence of numbers that seems to have no meaning.

Terra-P Radiation dosimeter MKS-05


The terra-p Radiation dosimeter can be used to measure Gamma, Beta and X-rays.

High Frequency Solid State Tesla Coil (HF SSTC)


My first SSTC as a high frequency solid state tesla coil.

Mains hum sensor – detect the power lines inside walls


Detect the power lines route inside walls with this simple Mains Hum sensor

CdS Photosensitive Vacuum tubes


A collection of a few NOS photosensitive vacuum tubes.

CreateProcess, GetExitCodeProcess and application crash


When using CreateProcess win32 API make sure the lpCommandLine is not a constant or your application can crash.

ATMega8 LCD Game


Create a simple game board and write a little software game for your ATMega8 LCD board.

First Atmega8 bot – (Arduino board)


An article about a differential Arduino robot by Rodrigo Nascimento Hernandez

ATmega8 and Hall Sensor A1302


Atmega8 and an A1302 Hall Sensor for sensing the magnetic fields in close proximity.

Apple iPhone 3G – introduction


This article shows a few basic things:
– How to connect your iPhone to your desktop PC and how to update the iPhone firmware
– How to downgrade the iPhone 3G from 3.1 to 3.0
– How to activate the iPhone 3G 3.0 (jailbreak)
– View iPhone filesystem in total commander
– Do screen captures of your iPhone 3G

Perseus 3 Advanced Robot (using Windows Mobile)


Perseus 3, a 4×4 advanced robot featuring an Atmega8 for sensor interfacing and motor control, and a I-mate SP5 smartphone (200MHz) running Windows Mobile 6.0 as robot’s brain. Small weight, powerful trust, and lots of features including WLAN, Bluetooth, Camera, Speaker, Phone-interface (GPRS, 3G), Microphone (for voice commands) and more.

Android tricks: Disable “No SIM card” screen


Disable the “No SIM card.” annoying Android message.

GU81M VTTC a different approach


High Voltage Power supplies


An article on various high voltage sources. Includes schematics, construction details, high resolution images and videos.

Homemade Capacitor 19nF/10KV


How to make a high voltage capacitor in a few steps. See a video with my 19nF/10kV capacitor, with under 1$ cost.

ARA – differential robot platform


A new differential robot platform, with strong gear motors and low power consumption.

Aspell word lists / dictionaries for several languages


How to extract huge word lists for most languages, using the Aspell dictionaries.