
My 555 Circuits here - Schematics of delabs: 555-Circuits
Hobby Electronics, Amateur Radio, Do it Yourself Projects, Kits.
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From Soldermans Basic Electronics |
Mains Voltage Stabilizer Circuits
These circuits were drawn for a person in Africa. See the thread here… stabilizer circuit. They were not tested by me, but are quite close to a practical design.
Stabilizer Step up 230V AC 500VA
This circuit is a design i did, not tested by me as yet. It can Stabilize Mains voltage to around +/- 10% . It can be used for both 110V AC or 220V AC inputs with modifications. The Output is 220V AC. There is an overload, under voltage and over voltage trip circuit. With some tweaks and modifications it might work.
Solid-State Stabilizer Step up 110V AC
This circuit is a design concept, not tested by me and i did it just to explain some ideas. The circuit uses opto-coupler MOC3041 of Motorola and the Triac BTA-16-600 of ST as a solid state switch or relay. It also uses the LM324 quad opamp from National Semiconductor which is low power and single supply. As the MOC3041 switches the Triac at zero crossover there is no inter-winding short of transformer on crossover hopefully, the control circuit is designed in such a way that more than one triac will not be turned on at a time, i would like you to give feedback.
The Center piece is a bamboo tube. The bottom of this pipe is a brass part. A autotransformer dial is the big washer. The LED array is from a Failed China Lamp and The Enclosure is a 10 CD Box. The Top Byzantine Structure is a Pepper Cap from Africa and a Furniture Knob.
Perpetual Candle - White LED Lamp on Ni-Cd
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From Hobby Hound - DIY Electronics |
Read Earlier Post - Perpandle Design
This is a easy to build LED lamp circuit for Learning and building skills. This is the first draft schematic V 1.0. It will need improvements for Higher Power Lighting.
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From Schematics of delabs |
I will give a short summary, The LM317 here configured for around 6.4V DC. The Q3 BC547 limits the current, you can select R3 to suit, make it 1/2W. The Ni-Cd battery pack 1.2 * 4 will not get Over-Current or Over-Voltage due to this circuit.
The IRF540 Mosfet or any other equivalent you have around, along with Q2 BC547 forms a current source for the parallel 12 LED array. Ultra-bright White LED at 20mA each or use a 1W ready LED Chip. R4/R6 can be selected for the Max LED current. The voltage of LED is around 3.1 and 20mA * 12 = 240mA is the max current. You can Tweak the design for even 5A or more but then you will need a DC/DC High frequency converter in place of LM317. The Current source also needs to switch to improve efficiency. A PWM on the mosfet gives brightness control. The entire solution (switching) can be found in many chips with semiconductor vendors today.
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From Hobby Hound - DIY Electronics |
One Single High Current LED may work well. 12 Matched LEDs also can be used. In LED Array some are dim, put min. resistor (3.9 ohm) for all 12 for current sharing. The resistor addition will impar the ability of Candle to work at lower battery voltages. Also resistor is less green, It wastes power, so use PWM and Single Die high current LED. Ni-Cd system may last over 5 Years if Candle is allways on Mains. Sealed Lead Acid system may go upto 2-3 years life but will have more punch. A SuperCap system may last more than 12 Years, i feel.
Source in Cadsoft Eagle format - candle.zip
Circuits based on AVR microcontrollers (?C) from Atmel. "little powerful things"
AVR Circuits by Vassilis Serasidis - AVRsite
A mega32 based low speed oscilloscope. It can be used to measure signals up to 5 kHz. The input voltage range can be up to 24V AC or 30V DC. Designed by: Vassilis Serasidis - Language: C ( AVRstudio4 + WinAVR )
Make your own PCB Mechanical Routing/Erosion/Milling Machine at a low cost.
PCB Mill - Jonathan Ward - MIT
"Design a low cost circuit board milling machine optimized to be mass-produced."
The overall device has a working area of 4" x 6" with a footprint roughly the size of a letter-sized sheet of paper. Capstan drives were chosen for their simplicity and low cost, and also serve as torque limiters to prevent excessive loads on the small-diameter drive cables.
The story and evolution from Behemoth to Microship, water-type HPVs. microship.com. Technomadic goodness.
Nomadic Research Labs and Steve Roberts
Surplus Kayaking Books Parts Sensors Nautical Controllers GPS Trackers Geek-free Zone marine electronics.
This site uses hands-on experiments to show the basics of how real things in the real world are controlled with computers.
Controlling The Real World With Computers
This site is also for anyone who is the least bit curious about monitoring and controlling such things as motors, lights and switches, or recording and playing everything from sound to the arm position on a robot.
Experiment 7 - Bi-directional Control Of Motors And The H-Bridge
It would be useful to be able to run a motor in either direction. That's simple with a motor of the type that's been used in the experiments thus far. Reverse the DC power connections on such a motor and its shaft will rotate in the opposite direction. One way to control direction is to use switches arranged in the following manner:
VeeCAD takes a schematic generated netlist and assists you to build a layout - but on stripboard (Veroboard). The usual design tools are provided: netlist import, component footprint definition, component positioning, wiring and connectivity check.
VeeCAD for Stripboard with Auto Router
Engineers and hobbyists use VeeCAD for prototypes and small quantity builds, saving hours planning layouts on graph paper.
Transistorized from - PBS Online - Tutor
Lesson 2: Scientists at Work
Students select an electronic invention and research who and what contributed to it.
Lesson 4: Using Transistors
Students build circuits to see how transistors function as switches or amplifiers
TechLib - Electronic Experimenter Records
A technical library for the hobbyist and experimenter. - Charles Wenzel
This will be a collection of unusual ideas for somewhat difficult science fair projects - hopefully not a repeat of other sources.
Specialists in very high quality audio, Designs Amplifiers, Preamplifier, Phono Preamplifier and R-evolution Turntable etc.
Adapting New Technologies into Classic Hi-Fi systems, without compromising on Decades of Audio tradition.
MITA The Mains Independant Tube Amplifier
SE battery tube amplifier
Features
Stereo SE 15w / Channel, Three Silver Rock transformers per channel, Fully Lithium battery powered, All silver internal wiring, Veneer to customer's request.