Monday, April 06, 2015
Here is the first page that will interest you - Parasitic Power Shoes Project
"environmental energy sources can begin to replace batteries in certain wearable subsystems. In this spirit, this effort has examined devices that can be built into a shoe, (where excess energy is readily harvested) and used for generating electrical power "parasitically" while walking."
Piezoelectric Energy Scavenging In Shoes
Goal: To develop a rugged piezoelectric shoe insert and complementary conditioning electronics for unobtrusive, parasitic harvesting of the compression energy normally lost while walking
Wednesday, October 09, 2013
Voltage Monitoring is an Electronics board that allows you to connect 5 to 14VDC on one side of the board and get it corresponding LEDs light on the other side. Every Car, tractor or boat should have one.
Battery Monitor for your Boat or Car
The boards will allow you to easily monitor your 12V battery while powering from the same battery. The Terminal Block TB connector is included and makes it easy to use.
The LM324 is the Heart or Intelligence in this Circuit. There is a voltage divider and zener too. They have a kit and pcb to buy and build .
A battery of a car can drive enormous amount of current, anything that is High-Voltage, High-Current or High-Frequency or a combination of these; are known to be high energy circuits. So as a precaution when you wire the positive to the car battery use an automobile fuse with holder like the one used outside the stereo player. The fuse has to be outside!
You could also use a fusible resistor in a metal box and keep it outside, the 12V positive has to go thru this. Any car/boat project needs this. A short circuit on PCB or Wire will blow fuse and everybody is safe.
Got it ..
Tuesday, November 20, 2012
Develop a Skill this Christmas, Build these small LED Trees and give it to people who need a little bit of cheering up.
Christmas Tree - CircuitStew
"This was the first and last complete prototype that I made on proto board. This style of prototyping produces circuits that are very difficult to understand, debug, and modify. Because of all the extra work involved they also take forever to assemble. Suddenly I became very interested in designing and fabricating custom pcbs...."
The name CircuitStew refers both to the jumble of electronics presented here and to circuit boards suspended in neon green copper etching solution. - Derek Wolfe
Thursday, March 15, 2012
The following was submitted on July 11th, 2007 at 12:47AM (PDT).
Message: I want to combine Ne555 with 74154 IC.The indication of the outputs must be shown with LED's but up to so far it need 15 outputs ,is it possible the way i did? if not i will need your assistance
Mail from CY
See these circuits you will get an idea, Using CD4514 is also possible.
Tuesday, October 11, 2011
Jonathan Westhues site of Intriguing Projects include A Test Instrument for HF/LF RFID and a compiler that starts with a ladder diagram and generates native PIC16 or AVR code.
I sense the load current and control the duty cycle. The PWM pin on the AVR drives the gate of the FET through a couple of BJTs. Note the absence of any input capacitance; Vin looks terrible but it works. The micro power supply section is isolated with an RC.
This is a nice way to start, learn uC and Power electronics in one go. It does not matter if it an expensive solution for LED Lighting. It certainly is an excellent Educational Project.
It may also be useful to use Intelligent Systems (uC and Firmware) to monitor and manage LED Arrays and control their brightness and color. Large Arrays can be Interfaced to PC by XBee for Home/Office or Factory Lighting Automation and Energy Consumption Optimization.
uC Real World Interface
uC I/O is Keyboard and LCD when you Build a calculator or a Text/Morse Communicator. When you control a motor it is Drive/Speed and Direction for Motor and Tacho or Opto Counters for Feedback. In both cases you have Input and Output which is Logic or Analog which has to reach the CPU.
Saturday, March 26, 2011
LM3914 - Versatile and Easy use Display
- Drives LEDs, LCDs or vacuum fluorescents
- Bar or dot display mode externally selectable by user
- Expandable to displays of 100 steps
- Internal voltage reference from 1.2V to 12V
- Operates with single supply of less than 3V
- LED driver outputs are current regulated, open-collectors
My LM3914 Circuits
Millivolt Meter using a LM3914 LED Dot Display
LM2941 Manual Fan Regulator & LM3914 Voltage Monitor - The LM3914 voltage monitor is also straight forward. As told I use only 6 of the 10 led outputs. A voltage divider on the input (R1-R2) decreases the 7-12V input to about 1.96-3.36V (x0.28).
Indikátor napětí autobaterie s LM3914 - This is actually a voltmeter that the size of the measured voltage signals using ten LEDs. The level of which will illuminate the first LED and the lights can be set to last.
Bauplan Schaltplan Bargraph Anzeige mit dem LM3914 - Analog displays have the undoubted advantage that you can get a reading very quickly perceives visually compared to digital displays.
Stereo Digital Camera Sync Shepherd - R7 sets the current through the LED's of the display. With R7 of 620 ohms, the illuminated display LED draws about 20 mA, which is about maximum for this display,
DIS*PLAYER: Theory and Construction - This device drives ten LEDs in a linear display, with programmable endpoints and the choice of "dot" or "bar" modes of operation. Furthermore, it is possible to "chain" multiple devices for displays of virtually unlimited size.
Monday, June 23, 2008
A Hobby now in your School days or College can help you build a strong profession later. It is Edutainment that will make productive use of your spare time. Friends can do it as a group, during holidays. Parents should encourage healthy hobbies, as the children will grow in a positive and creative atmosphere.
Stereo led level meter - This is it. It's a STEREO LED LEVEL METER. It's the cheapest and best bar graph display available and best of all, it uses readily available components.
VU-meter by Archy - Then it hit me. A VU meter, big, beautiful, professional! From that moment started my thoughts flowing. Those VU-meter ICs that are sold in every electronics shop?
LM3914 dot-bar display driver - The LM3914 is a monolithic integrated circuit that senses analog voltage levels and drives 10 LEDs, providing a linear analog display.
Knight Rider Display Project - This project started out as a VU meter. I reused parts and pieces to improve the VU meter and give it additional functionality. It is amazing how much time it takes to create a small thing like this.