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6 Mar 2015


by retrotext.blogspot.co.uk:

I have just recently had solar pv installed, mainly to future proof my energy costs, I do not expect it to be like drilling for oil in my back garden, however the return looks to be encouraging.

The install gives you another single unit meter, from this you will see the total amount the panels produce, but that is about it.

I wanted to know how much the production was as it was happening, I discovered the light blinks on the front of the meter will flash 1000 times for each kWh of electricity which passes through. The rate of the flashing of the LED tells you how much power is currently passing through the meter.

A basic Arduino Solar PV Monitor - [Link]

5 Mar 2015


This is a small 2 Channel amplifier constructed around Sanyo’s LA4445 IC delivers 5.5Watts +5.5 Watts at 4 ohm load, supply in 12V DC 2Amp, Input impedance 30K.


Dual Channels output : 5.5W
Minimum External Parts
Very small pop noise at the time of power supply ON/OFF
Good ripple rejections
Small residual noise
Built-in protectors 1. Thermal Protector 2. Overvoltage Surge Protector
Standard Audio signal
Supply 12V DC
Load : 4 Ohms Speaker on Each Channel
Voltage Gain : 50DB
Output 5.5W on each Channel (THD 10%)
Total harmonic distortion 1% Max @ Po=1W
Input impedance 30 K-ohms

5.5W – 2 Channel Audio Amplifier - [Link]

5 Mar 2015


A thermometer is utilized to quantify the temperature of solids, liquids, or gases. A thermometer contains a fluid (normally mercury or a liquor arrangement) in a supply whose volume is directly reliant on the temperature (as the temperature expands, the volume increments). At the point when the fluid is warmed it ventures into a thin tube that has been aligned to demonstrate the temperature. Temperature can be recorded in Celsius, Fahrenheit, or Kelvin, accordingly it is imperative to note which scale the thermometer is balanced for.

This Do It Your Own (DIY) digital thermometer circuit can measure temperatures up to 150°C with an accuracy of ±1°C. The temperature is read on a 1V full scale-deflection (FSD) moving-coil voltmeter or digital voltmeter.

Operational amplifier IC 741 provides a constant flow of current through the base-emitter junction of NPN transistor BC108. The voltage across the base-emitter junction of the transistor is proportional to its temperature. The transistor used this way makes a low-cost sensor. You can use silicon diode instead of transistor. The second operational amplifier is amplified by the small variation in voltage across the base-emitter junction, before the temperature is displayed on the meter. Preset VR1 is used to set the zero reading on the meter and preset RV2 is used to set the range of temperature measurement. Operational amplifiers operate off regulated ±5V power supply, which is derived from 3-terminal positive voltage regulator IC 7805 (IC1) and negative low-dropout regulator IC 7660 (IC2). The entire circuit works off a 9V battery. Assemble the circuit on a general-purpose PCB and enclose in a small plastic box. Calibrate the thermometer using presets RV1 and RV2. After calibration, keep the box in the vicinity of the object whose temperature is to be measured.

Digital Thermometer Circuit - [Link]

5 Mar 2015



VFD Modular Clock IV-18 SMT edition is a special solder-free kit version of the original VFD Modular Clock . The firmware is mbed based and is freely available at http://developer.mbed.org/teams/Akafugu/code/vfd_modular_clock_mbed/


  • IV-18 8-digit Russian VFD Display Tube
  • Open source mbed based firmware
  • LPC1347 ARM Cortex-M3 64kb microcontroller
  • GPS (option)
  • Four Letter Word
  • Easy to update firmware with no special drivers required (LPC1347 usb bootloader)

VFD Modular Clock IV-18 SMT - [Link]

5 Mar 2015


The miniSpartan3 is our new, low cost, tiny, FPGA kit. It starts at just $25, and there is a more powerful FPGA chip available for $35.

  • The Spartan 3A XC3A50 FPGA ($25), or the Spartan 3A XC3A200 FPGA ($35) from Xilinx.
  • An on-board USB JTAG Programmer to power and program your FPGA.
  • An on board USB to Serial Interface.
  • One HDMI port.
  • 41 digital I/O pins.
  • A 4-channel analog to digital converter running at 200 KSPS with 8 bit resolution.
  • 4 Mbit SPI Flash.
  • 32Mhz oscillator.
  • 3 LEDs for debugging.
  • 2 DIP switches.

miniSpartan3 - [Link]

5 Mar 2015


The Emic 2 Text-to-Speech Module is a multi-language voice synthesizer that converts a stream of digital text into natural sounding speech. Using the universally recognized DECtalk text-to-speech synthesizer engine, Emic 2 provides speech synthesis capabilities for any embedded system via a simple command-based interface.

EMIC 2 Text-to-Speech Module - [Link]

4 Mar 2015


by Stephen Evanczuk @ digikey.com:

Indoor lighting offers a convenient energy source for many applications but lacks the high-power levels of solar energy. In fact, indoor lighting energy-harvesting systems face a number of challenges that differ subtlety from those encountered in solar-energy harvesting. Nevertheless, engineers can quickly implement energy-harvesting designs using a variety of components and specialized devices from manufacturers including Cymbet, IXYS, Linear Technology, Panasonic, STMicroelectronics, and Texas Instruments, among others.

Specialized ICs, PV Cells Enable Energy Harvesting from Indoor Lighting - [Link]

4 Mar 2015


by Colin Jeffrey @ gizmag.com:

Dendrites – thin conductive filaments that form inside lithium batteries – reduce the life of these cells and are often responsible for them catching fire. Scientists working at the Pacific Northwest National Laboratory (PNNL) of the US Department of Energy claim to have produced a new electrolyte for lithium batteries that not only completely eliminates dendrites, but also promises to increase battery efficiency and vastly improve current carrying capacity.

New electrolyte promises to rid lithium batteries of short-circuiting dendrites - [Link]

4 Mar 2015


by DAVID BURGOON @ edn.com:

There are several ways to produce a negative voltage from a positive voltage source, including using a transformer or two inductors and/or multiple switches. However, none are as easy as using the LTC3863, which is elegant in its simplicity, has superior efficiency at light loads and reduces parts count compared to alternative solutions.

The LTC3863 can produce a –0.4V to –150V negative output voltage from a positive input range of 3.5V to 60V. It uses a single-inductor topology with one active P-channel MOSFET switch and one diode. The high level of integration yields a simple, low parts-count solution.

AppNote: Inverting DC/DC controller converts a positive input to a negative output with a single inductor - [Link]

4 Mar 2015


Peter of Cytec BG writes:

My idea was for pcb designers to be able to quickly, without too much hassle, check their board for correct footprints (especially for connectors) and collisions between components. Currently one can change soldermask colors, silkscreen layers, move and rotate components around, change component models and import step files.


3D Eagle BRD Viewer - [Link]






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