Open Circuits – Open Source Electronics

Open Circuits is a wiki for sharing open source electronics knowledge, schematics, board layouts, ports and parts libraries. This include open hardware Music Players, atomic microscopes, PC, PDA and mobile phones, and batteries. Please help us to build this resource by submitting your component descriptions, projects, techniques, and PCB footprints.

Open Circuits – Open Source Electronics

Some Projects that look Interesting are

  • Multi-purpose Embedded System
  • dsPIC33 Development Board
  • ADuC832 Development Board
  • N8VEM Home Brew Computing Project

The Open Source Movement, typically covers Open Hardware, Open Firmware, and Open Software. The Open Firmware movement provides firmware which you may also know as soft-IP or FPGA coding see Open Cores for more details.

Excellent examples of Open Hardware projects range from projects at OpenCircuits to Tiny Embedded Ethernet Devices and Advanced & Intelligent Camera Designs which provide solid-state camera and FPGA assisted hardware designs. A solid overview of projects can also be found at Open Innovation Projects.

OpenEEG Project hardware – Amplifiers

The OpenEEG project is about making plans and software for do-it-yourself EEG devices available for free (as in GPL). It is aimed toward amateurs who would like to experiment with EEG.

OpenEEG hardware – Amplifiers

OpenEEG hardware - Amplifiers

I found the amplifier designs extremely good as a learning material.

– ananth

Design documentation

Amplifier schematic [55kb] (aka analogue board; contains two amplifiers) and digital board schematic [48kb] as images.

Bill O’Donnell – Tech Gizmo Builder

These are high tech jigs, fixtures and instrumentation/automation gizmos that bill built. Electrical gizmo builder for the UNLV Physics Dept.

Bill O’Donnell – Tech Gizmo Builder

These projects are advanced and not for a beginner student or newbie hobbyists. These pages are knowledgable and will help students and DIY enthusiasts understand more about Lasers, Precision Temperature Control and stepper motors among other things.

Bill Tech Gizmo Builder

Auto Fill Circuit for Laser Cooling Loop – Ethernet Data Logging

Here is an automation solution with a ethernet usage. The code and diagrams are also there. This is something that covers many aspects of engineering in one project. Try such things out to learn, only after you have mastered the basics.

“The Ethernet connection is based on an XPORT form Lantronics. Basically it lets you use a serial port to send things over Ethernet. A PIC microcontroller with an A/D converter digitizes the pressure, the pressure set point, the high and low pressure alarm points and the supply voltage (since everything is ratio-metric). “

Professor Mark Csele – Projects and Hobbies

“I present, below, a collection of projects I have worked-on over the past few years. For over a decade, I had taught both embedded systems (microcontroller technology) and digital signal processing and practice what I preach….”

Professor Mark Csele – Projects and Hobbies

Nixie Thermostat – A heating and cooling thermostat employing technologies spanning fourty years from the unique Nixie tube display, circa 1960’s, to a PIC 18F microcontroller, circa 2006.

A High-Powered Power Backup Inverter

A High-Powered Power Backup Inverter – The working prototype of the 2 KVA inverter is complete. Fed from an array of lead-acid cells totalling 600 Ah (at 12 Volts), it easily drives real-world loads such as single-phase motors. The inverter has been tested and found to operate at an efficiency of between 71% and 82% driving a variety of both inductive and resistive loads

Digital Electronic Stethoscopes

The Heart, Liver and Kidney form a Vital Organ Tripod, on which rests the most Important Organ… Think about it……You are Thinking with it. Rack your Grey Matter with your copy of the Gray’s Anatomy; to figure this Puzzle within.Digital Electronic Stethoscopes

Any of these three Legs, of this Tripod, Can be affected by wrong eating and living habits. After a certain age, you have to only Eat what you can burn, The rest is Poison. An electrician knows, If an Equipment is rated for for 12-Volts 3-Amps; He has to use within its Limits. An Electronics Engineer knows that he should never go near the “Absolute Maximum ratings”.

Study more about the Vital Organ called Heart, by building an Electronic Stethoscope. See the Block Diagram (SBD) – Digital Stethoscope – TI.com. The sounds are very faint and a low frequency. It is a Bionic Challenge to acquire and amplify these small signals. Learn more about these concepts here …

The SS30L Electronic Stethoscope will allow you to record and listen to heart sounds and Korotkoff sounds.

Here is a another Semiconductor Application from Maxim-IC Digital Stethoscope.

More Reading –

Multi-Instrument Digital Assistant – PIC16F84A

Multi-Instrument Digital Assistant – PIC16F84A

“It contains four instruments in one unit: logic probe, single channel logic state analyzer, frequency counter and serial code receiver.”

From Hobby Hound – DIY Electronics

The Engineer’s Assistant – Erik Grindheim

Serial code receiver The serial code receiver receives 42 bytes and displays them in both HEX and ASCII. The baud rate is selectale in 8 steps from 1200 to 115200.

Logic state analyzer This is a one-channel logic state analyzer. It fetches 300 single bit samples in a selectable rate from 25ms to 1µS (40 Hz to 1 MHz in 16 steps).

Frequency counter The frequency counter displays the frequency with up to 8 digits on the LCD. The refresh rate is 500ms.

Logic probe The low and high logic levels are displayed by LEDs which are OFF if the probe tip is floating.

Optical Retro-Reflective Proximity Switch

This circuit is used to detect objects by reflected infrared light. It can be built into a cylindrical enclosure just like an inductive proximity switch. This is also useful as a level detector for colored liquids like oil. This has some immunity to ambient sunlight as it detects ac pulses.

This is a Hand Crafted PCB Artwork done by a PCB Vendor years back, this method may be used even today.

Optical Proximity Switch - PCB

PCB Design –

This Layout may have many jumpers and may need to be cleared of Hairline shorts which has happened after i scanned it, cleaned it and enhanced it using image manipulation software.

This PCB would go into a 30mm Nickel Plated Brass threaded tube, with Epoxy or Teflon ends. These were turned components as quantities made were small. An Optical Proximity Sensor that would fit the same place as the eddy current or Inductive sensors, in existing machines. It could work a longer distance and could detect Non-Metals and even translucent fluids.

You can design your own PCB with CadSoft Eagle Layout Editor. Laser prints of output works well, but even Ink Jet printouts will work fine for small PCB’s like this. Take 3x or 4x prints.