From Open Circuits
Ideas before they become OC projects:
- Portable Context Device
- Open power connector for mobile phones, PDAs and laptops. (Wikipedia lists a variety of connectors -- or were you looking for an AC power connector? What sort of specification do you want?)
- "Open Source Disability Gadgets: DIY for PWD"  "Gear and software for people with disabilities is usually provided through charity or from medical supply companies. It's hard or impossible to repair it, or get anyone to repair it. We need to hack the model for accessibility tools! With a culture of open source designs, Instructables, wikis, and blogs, we can start an international movement."
 open design laptop
- Open design laptop (you can replace the components). (see computer component wiki: custom notebook)
-- OCZ has an open design customizable laptop here. --BlueFusion
How do I make a laptop with 2 independent internal disk drives (so I can do RAID 1)? --DavidCary 21:31, 5 September 2008 (PDT)
 better data cable ideas
- Open data cable. Random good ideas: "One under-appreciated attribute is that the moving parts of the connector are on the cable side, not the system side; when the connector begins to show some wear and tear, the cable is thrown away, not the PC (or printer, or disk drive, or camera)." -- Michael Teener  ... Many popular data cables also include power (Power over Ethernet, FireWire -- but not the iLink variant, USB)... What voltage? extra-low voltage ? ... Is it better to have the same connector on both ends of the cable, or have different connectors? Same connector allows peer-to-peer arbitrary mesh; different connectors afford/suggest a tree topology ... putting 2 connectors on every device, "upstream" and "downstream", allows linear daisy-chaining; 3 identical connectors allow any arbitrary-dimensional topology ... the round pins vs. flat blades (vs. other connector shapes) controversy ... optical isolation (like MIDI hardware) seems like a good idea ...
- When someone trips over the cable, destruction of the fixed socket is unacceptable -- but is it better to destroy the cable, or to let the cable pop out -- like MagSafe? ... twisted pair for power, and twisted pair for data ... Some data line codes (such as the one used for USB) are designed to work even when the twisted pair is accidentally twisted an extra half-twist; is it worth arranging things so the entire plug can be plugged in with an extra half-twist with no problems (like automobile keys and MagSafe) ? ... What's this I hear about non-contact power pads?
"What we would like to see is one cable that carries audio, video and power to or from whatever device you need to use. It needs to be small, it needs to have tremendous bandwidth (perhaps using fiber optics), and it needs to be smart enough not to ruin anything you plug it into. ... Please, someone round up all the consumer electronics manufacturers, and somehow make them all use the same connectors." -- Gizmodo.
Some commenters on Gizmodo have some interesting ideas:
- wireless for all data, wires only for power
- use a standard power connector -- Green Plug
- "something can be really good new, but how many tests have there been which rate performance over time? Especially with in-wall installations, this may be a very serious issue."
- "You can already do everything on a CAT5e cable network ... the next version of the PoE spec is supposed to allow for 56 watts of power per cable, which is more than enough for hard drives and such."
- "You already have it, its called FireWire."
- "we already had one cable for everything. It was coax. It was used for audio, video, even networking. But then people wanted better. The that pretty much messed everything up. Stop wanting more and you'll be fine."
A few commenters on Gizmodo seem to think it is impossible or unfeasible.
- "If it does all of that at the same time, it will need to somehow send and receive data at the same time- is that possible?"
- "This whole concept is ridiculous..."
- "There's money to be made in chaos."
- "some cables need a lot of pins and some don't and it would be silly to have a 24 pin connector for USB for instance, and it would be costly to have cables that have lots of pointless wires in it."
- "power inside the transmission cable? thats just asking for interference."
Understanding how cables fail might help us design better ones:
- "A Lesson in User Failure: Investigating the Serial ATA Connector" by Ryan Smith 2008
- "If I were a manufacturer of a delicate, expensive, high-quality precision instrument, I would design one-way connectors, so they could not be plugged in the wrong way. But Caviar does not share this philosophy." -- Carla Schroder
 LaTeX circuit diagramme markup
- Hello, I've just joined!
- I've just started using PmWiki as a "MyWiki" (home CMS/PIM offline personal desktop intranet wiki)(I've decided to call it a "MyWiki" rather than keep reeling off a description!)
- One of my main objectives in using this is to write up my electronics degree notes and sort of build my own encyclopaedia. Naturally, that means you have to use LaTex (haven't quite got MathML or jsMath to do as their told, but they work well enough for the meantime); and use of GraphViz is on the agenda for making block diagrammes, flowcharts; and (I hope!) making bode plots, smith charts, simulated 'scope readings, and what I'd really like is to make actual analogue circuits just by markup. I'm only just learning Java, and my PHP knowledge is pretty rank. Does anyone share my interest and want to set up a team to work on this problem? I think it'd be a great addition to this wiki as well!
- cheers! 18.104.22.168 04:28, 29 November 2008 (PST)
That sounds like a great idea. I see that Wikipedia's "WikiProject Electronics" is taking a few small steps in that direction. Have you seen Wikipedia: WikiProject Electronics#Drawing circuits and Wikipedia: WikiProject Electronics/Programs ? And the Techniques#Software_design_tools already available? --DavidCary 19:54, 14 December 2008 (PST)
 Multi PIO interface
I've been thinking about this idea for a while now, but I don't have the time, resources, or software coding expertise to see it into existence. The concept is sort of like Arduino, but would ease several limitations such as I/O bandwidth and program size. It could streamline embedded system development or make it possible for an old PC to to become the heart of very sophisticated projects. It could have the following features:
- 64 (or some other arbitrary number) lines of I/O which can be configured as:
- TTL input
- TTL output
- Analog input
- Analog output
- PWM output
- Multiple design versions (sharing a common code/design base):
- Fully open design/source - both hardware, and software
- Built from easily accessible (and preferably inexpensive) parts
- APIs for a variety of programming/scripting languages
(Please expand this list if you have an idea!)
There are a number of microcontrollers that could do the task with very few support components. Determining which one is right for the job would take a bit of reflection.
It would have hundreds of applications, and have enough I/O to perform several of them at once. It could be used to collect input and turn switches on and off for a simple home control system or run a model train set. It could be used to create software implementations of obscure communications protocols (such as Wiegand). It could be used to build very complex robots.
--Dovregubben 06:04, 12 June 2009 (UTC)
- Sounds like a great idea.
- I've been thinking about building something vaguely like this, based on the Parallax Propeller.
- However, it looks like someone took all your cool ideas and crammed them into the the Arduino Mega. The Arduino Mega has 54 digital input/output pins (of which 14 can be used as PWM outputs, another 8 can be used as 4 independent hardware UARTS, and 2 more can be used as an I2C port), 16 analog inputs, and a USB port. I think it also supports SPI.
- Is there anything else you wanted to do that the Arduino Mega can't do? --DavidCary 04:14, 24 June 2009 (UTC)
 open power connector
- See also: connectors.
I wish there was some kind of standardized set of power plugs, such that a 12 V power plug obviously would not fit in an incompatible socket
Even better would be an even more restricted standard, such that there wouldn't be a dozen different voltages available between 1 V and 100 V, but instead only one or a few voltages, such that randomly swapping power adapters I would have a much better chance that everything "just works".
Is there an optimum shape for the power connector?
Some contenders for the "best" power connector:
- Many ham radio operators make all their equipment run on 12 V and a red/black Anderson Powerpole connector. Wikipedia: DC connector#Anderson Powerpole connectors
- Dale Davis makes all his equipment run off 12 V, and uses a standard cable everywhere with identical barrel power plugs -- center positive, barrel ground -- at both ends. Barrel Power Jack. The outer barrel is ground so that if a one end of the cord is plugged into 12 V power supply and the other end touches a metal case (which is always grounded), it's harmless. A nice feature of barrel plugs is that you can plug them in at any angle, and it Just Works.
- The Green Plug universal power adapter
- The Alliance for Universal Power Supplies
- Some people are using USB cables and USB host sockets as a "universal" source of (small amounts of) 5V power, by default 150 mA (0.75 W); with smart negotiation up to 900 mA (4.5 W).
- "Europeans Charge Each Other's Phones": "All the major cellphone providers of Europe, including Apple, agreed to make phones powered by micro-USB charging slots going forward."
- Some people are using special "powered USB" sockets and cables to carry 12 V at 6 A = 72 W.
- Some people are using CAT5e Ethernet cables and power-over-Ethernet (PoE) as a convenient source of up to 30W of DC power.
- "wireless power transfer" pad.
power connector review: Stefan Vorkoetter ("Electric Flight Power Connectors" 2006) reviews several kinds of power connectors, points out some non-obvious features that are nice to have in a power connector, and makes some recommendations on which to use and which to avoid.
Is it possible for the device to "negotiate" for exactly the voltage it needs, such that the same power adapter provides different voltages to different devices?
- Perhaps the device could include a resistor+zener voltage divider to produce a feedback voltage precisely half of the voltage it desires?
- Perhaps the device could include a resistor+resistor voltage divider or resistor+zener voltage divider to produce a feedback voltage precisely 1.25 V lower than the voltage it desires, so a LM317 or equivalent regulator will produce exactly the desire voltage?
- ... in such a way that the power adapter automatically produces 0 V or "disconnected" soon after any device is unplugged. (hmm.. that would not be the case using the LM317...)
- ... ?
 micro controller based voip client
A wireless micro controller based voip device, capable of working independently of a full blown computer system.
 Model Rocket Launch Controller
I know, there are a bunch of these projects on the web, but a good, truly open source one can't hurt. Plus, I'd like to develop one with an optional, largish countdown timer display for public launch days. (which I have seen talked about, but never written up well)
Some possible features:
- A "hold-to-fire" or deadman safety switch - Pressing the FIRE button actually starts an auto sequence that counts down from a pre-programed time and then fires - key-locking safety arm switch - LCD or LED display at firing position - remote countdown timer(s) for audience - controller and accessories pack into sturdy, weather-tight case for transport/storage - ability to control/sequence multiple firings(?) - GO/NO-GO polling/voting system and display(?)
- 6.5" Seven-segment Displays (reported visible for ~100') http://www.sparkfun.com/commerce/product_info.php?products_id=8530 - Deadman/pendant switch (http://www.newark.com/switchcraft/e903/pendant-switch/dp/22F243)
What processor to use?
- Arduino/ATmega? (popular, available, relatively cheap, open source, probably a good one for me to learn) - MSP430? (Fun, have a bit of experience, huge family range, low-power for battery conservation) - PIC? - Basic Stamp? - 68HC11/12?
 Open PRO Audio Interface
- Firewire based with openhardware / drivers for Pro quality audio recording
- Interface which can be used with Laptops or Desktops
There is a distinct lack of audio interfaces compatible with Linux, most manufacturers of interfaces do not support Linux, the ones which do are usually on the higher end of price scale and changes to hardware architecture often breaks compatibility with the reversed engineered drivers made by the community.
Something affordable with say 8 or 10 in and outs which can record @ 24 bits @ 44.1/48/88.2/96 kHz would be very popular with Linux Audio enthusiasts.
I'm not a technical expert and don't mention USB interface as understand that this is less capable at handling the higher sampling / bit rates. Some commercial manufacturers do make USB interfaces that can record at 24 bits but do this using propriety drivers, if this is possible a USB based interface would be more accessible and open more possibilities !
 Electronic Legos
Currently rapid prototyping consists of getting a few boards and chips, doing some soldering, finding the right libraries for communication, and then writing some programs. I'd like to see an open design for snap together components which includes the case. Imaging a Lego blocks each of which contains a micro-controller, sensor, radio, battery, or ... You just snap them together and communication uses a standard library. A small ASIC in each block provides the networking layer and translation to the appropriate protocol for the on board chips. Currently I'm thinking a 4 wire connector with, +3.3V, GND, Clock, and Data would be the way to go. It could use standard modular phone connectors to make the connection since they are cheap. Something like this would open up the rapid prototyping world to anyone with programming skills for the micro-controllers. A good set of building blocks and a GUI on the dev kit could open up the design even farther. It should also drop the price of eval boards, since they should then consist of a single block.