Category Archives: Tools

EveryCircuit: Chrome killer app for electronics enthusiasts

I recently added an app to my smart phone and, as a side effect, added another app, and  that led me to stumble upon the web site, which provides electronic circuit editing/simulation/presentation tools together with commercial and crowd sourced example circuits.

For those whose religious convictions or practical circumstances make Chrome available on a laptop/desktop, the rest of this page might be interesting. Likewise, if you have a spare $10 the Android or IPhone apps might be interesting. So far, the Android version “just works” on my phone and I personally rate it “Uh, I’ve got to put my socks back on.”  Finally reading the site’s terms of use use might be a good idea for some people. I carefully read every word, something I rarely do. But I was relieved to see that the EveryCircuit people (currently) appear to stop short of claiming copyright on crowd sourced circuits.

To check this site out, try this link to the user-submitted rectifier circuit example above inside an instance of the Google Chrome browser on a desktop or laptop computer:

Visit rectifier example

Now  click the moving squiggle in the upper left. It expands to a pretend oscilloscope showing voltage and current vs time for one part of the circuit.

Now click the “edit this circuit” link. There are tools for modifying this circuit.

Cool, heh? The main site page is here.

Yes, again, this tool isn’t supported in many, many settings that readers of this blog find themselves in. It’s completely dependent on Chrome.  On behalf of the company owning this site (that I just found: I have no connection to it), I’m sorry it isn’t more portable.

By the way: Anybody reading this is welcome to submit their impressions of this or anything else here as comments below. TriEmbed meeting attendees or their online friends (such as in Vermont) are invited to request a blog account if they have interest in adding content to this site via blog postings, additional project pages, etc. Your access  will be proportional to how well you’re known to the admins and editors (but we’re always looking for new editors and at least one additional admin!) It takes about 10 minutes with somebody who is WordPress fluent to learn how to add content.

Open standard for connector/wire-free charging adopted by major car manfacturers

Open Dots Compatibility Logo


Ford, Chrysler, RAM, Dodge, and Scion have embraced an open standard for conveniently recharging portable devices that appears to be more effective and just easy to use as inductive charging systems. It’s called Open Dots.

The basic idea is to use a set of four parallel conductive strips to carry positive and negative voltages (or +V and ground, depending on your point of view) and have the package of a device to be charged connect to the charging strip automagically just by resting on it. The device to charge has a pattern of four conductive “dots” on its case that will properly connect with the charging pad in any orientation. This scheme was invented for recharging toys in 1963.

I’m sharing this as a potentially handy way to deal with the general problem of recharging battery-operated gadgets. It would take a fair amount of work to implement the pieces and parts involved with the actual electrical connections, but based on  the specification this is on the other end of the scale from rocket science and one would hope that the basic components may be or become cheaply available if the auto industry is involved .

As far as I can tell from their web site anybody could freely use these circuits and connector specs without consequences. (In order to sell something using the Open Dots logo one would need to execute and abide by a member agreement. But you do not need to get within a mile of this logo and could simply use the specs and reference circuits freely until you start selling a ton of stuff and see an advantage to becoming “official”.)

(Open Dots logo used without permission.)

Alternative short distance rangefinder: measures light transit time, not reflection angle

Here’s a device available on a pair of Sparkfun boards that Rod pointed us and Triangle Amateur Robotics to:

Update from Rod: A sensor + ARM M4 eval board for $20 from the chip maker:{13079d06258ef9010cea88dee32f3cdfc6f216a54651010f7303ce6140ee927c}252b49cDybCa83Lgq8kEXU{13079d06258ef9010cea88dee32f3cdfc6f216a54651010f7303ce6140ee927c}3d

Why Indeed?

At a recent meeting Scott Hall told us about a $4 Cypress ARM system that his work group intends to use with a port of  an ultra-lightweight Linux called uClinux. Coincidentally there was a recent blurb on Slashdot about uClinux on a Motorola 68k and here is the article, the related Youtube page, and one of the subsequent (in my opinion, classic) /. comments about this subject. The Slashdot article is here.


Parts Inventory Application

Hi all,

I have been working on a parts inventory site for a few years now. It currently permits a single user to keep his/her inventory of parts. It is my intention to expand the code base so that it will permit multiple users to keep private inventories and allow groups of users to have an inventory for specific projects.

The application is written using the Python Django Web Framework. I build websites using this suite of tool professionally.

What I am asking this group to help with are ideas of what may be useful functionality, in other words what would you like as features if you wanted to use such an application. I’m in the gathering requirements stage of the design, so we are still a ways off from a working system.

Some of my current ideas are:

  1. Multi-user
  2. Collaboration between users and project areas
  3. Search engine
  4. Track manufactures
  5. Track distributors
  6. Parts cost
  7. Parts categories
  8. Part pick location

The specific details of the list above are not worked out as of yet. This is something that I could use some suggestion about. For example, how would different user need to interact? What are reasonable categories?

The current site only runs locally on my home computer. It has no security as of now, so I cannot put it on my public site as of yet.

I will eventually add images of what I have now to give people some ideas.



Soldering Ventilation System

Some time ago I got one of the cheapo T-962 reflow ovens. It requires good ventilation. After running it in the garage, propped in a doorway and other kludge settings I implemented an effective ventilation system.  It actually came out a bit more “enthusiastic” than I intended.

I built a high performance, 8″ axial fan into the basement’s flue vent that had been used with a wood stove. The original goal was to tie this into a simple hood over the oven.

But I got a fantastic lead to an old but still active Craigslist item with a new low price (thanks, Steven Hausman of Splatspace!). I was able to buy a ductless fume hood with a huge carbon filter, squirrel cage fan and large adjustable enclosure for $100. Apart from the side with doors, two other sides are adjustable to create a “window” to suck air away from hand-soldering operations on a work bench.

The one small detail I hit when the hood  was sitting in the back of my beater pickup was that it would not fit through any door into the basement. I had to take it completely apart:


But it’s all together now and tied into the flue/fan system and working well.


The Amp Hour Redeems Itself Again

The Amp Hour has been terrible for the past couple of weeks. I’ve seriously wished for a refund of the few minutes of attention I paid them while listening and doing other things. ‘Nuff said.

However this week Chris and Dave have added one more data point to the curve suggesting that when they get somebody else into the conversation their podcast shines. This week’s episode is an interview of Eric Van Wyk, an engineer with amazing credentials. The specific Amp Hour web page for this episode contains many interesting details suggesting Van Wyk and company’s “Mooshimeter” will create immediate salivation if you’re part of the TriEmbed crowd.