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electronicsblog.net writes:
This is a very basic Atmega328 development kit It includes:
- Atmega 328 8 bit microcontroller with 20 MHz crystal resonator
- PCB board with place for external components
- Power circuit that allows powering Atmega directly(2.7-5.5 V), or through a L7805 voltage regulator(8-35 V). L7805 circuit includes a thermal fuse.
- 10 pin ISP connection for programming.
Atmega328 Development Kit Guide - [Link]
- Silicon Gamma Radiation Detector without GM tube
- Gamma-ray or X-ray detector with PIN photodiode
- When a Gamma-ray hits a depletion region on the PIN photodiode, it produces a small charge.
- As known as Photoelectric effect or Compton effect.
- The signal is generated as a pulse with amplifer.
- Electron pair creation is needed 1.022MeV at least.
- E value of Si is 3.65eV. When Si atom gets 3.65eV, Si puts out an electron.
- Visible light have between 400nm to 800nm wavelength. Gamma ray have under 10pm wavelength.
- Mainly Photoelectric effect under 60KeV, mainly Compton effect upper 60KeV
- Mainly Electron pair creation upper 6MeV
- Gamma energy of radionuclide have between 5keV to 4MeV. So rare electron pair creation without cosmic rays.
- Cosmic ray have strong energy.
- The lower energy come to high detection probability, the higher energy come to low detection probability.
- The detection probability on 10keV is 100%, but 1% between 100KeV to 1MeV
Gamma spectroscopy - [Link]
- Silicon Gamma Radiation Detector without GM tube
- Gamma-ray or X-ray detector with PIN photodiode
- When a Gamma-ray hits a depletion region on the PIN photodiode, it produces a small charge.
- As known as Photoelectric effect or Compton effect.
- The signal is generated as a pulse with amplifier.
Silicon Gamma Radiation Detector - [Link]
Sergei Bezrukov writes:
This projects is rather an experiment on how to build hardware for receiving the WWVB time signal and process it. The WWVB radio station located by Fort Collins in Colorado transmits atomic clock signal every minute by using a 60 kHz carrier (check here for the time code format). The strength and readability of the signal is monitored on the above website in four US cities located in four time zones: PST, MST, CST, EST. Although the closest to us monitoring city (La Crosse, WI) is about 200 miles away, the signal strength reported there matches our local conditions pretty well. Both cities are about the same distance away from Fort Collins (ca. 750 miles).
Receiving WWVB time signal with CME6005 - [Link]
electronicsblog.net writes:
This is a very simple capacity tester. It consists of single resistor that discharges battery. Arduino measures the voltage drop across resistor. According to Ohm’s Law current = voltage/resistance. Every second value of current is divided by 3600 and summed up to get the capacity expressed in Ah (Amp per hour).
I have used two parallel connected resistors that total resistance is 6.9 ohm. Make sure that they have proper power rating, if you don’t want them to convert to smoke. If voltage across 6.9 ohm resistor is 3.7 V, then current – 0.54 A, power ~ 2W.
Arduino Lithium-ion battery capacity tester/discharge monitor - [Link]
electronicsblog.net writes:
This is the very first and I hope not the last post of this blog. With this event I want to share with you LED calculator. It is also my first project with Visual C++ Expression 2008, this software development environment is free for students.
Calculator is capable of finding suitable standard E12 (10%) resistor value and power for one LED designs. There also some tips for user to find LED forward voltage:
LED resistor calculator for windows - [Link]
A 1-Wire port expander can be used to sense 8 push-buttons with only 2 wires. It can be powered via a strong pullup on the data line, so a separate power line isn’t needed – [via]
For applications that require less than a keyboard or numeric keypad, this simple circuit monitors multiple pushbutton switches using a single multi-channel 1-Wire addressable switch (DS2408), and a few external components.
App note: Sense multiple pushbuttons using only two wires - [Link]
Giovanni designed an Alcohol breathalyser [machine translation] using only an 8 pin PIC12F683 microcontroller, the MQ-3 alcohol gas sensor, and a 30 bar-graph breakout.
PIC12F683 alcohol breathalyser based on MQ-3 sensor - [Link]
Learn about Atmel’s latest version of AVR Studio. The new version supports ARM based microcontrollers so the name was changed from AVR Studio to Atmel Studio. [via]
Atmel releases AVR Studio 6 Beta - [Link]
dangerousprototypes.com writes:
LEDs don’t dim well using a an adjustable resistor, instead a pulse-width modulator is usually used to blink them rapidly giving the appearance of less light. Giovanni brings the analog charm back to LED dimming by controlling brightness via an adjustment knob (machine translation). This dimmer reads the value of an adjustable trimmer resistor with an analog to digital converter, and adjusts a the PWM output accordingly.
LED dimmer using an analog knob - [Link]
