This circuit features a part I only learned about recently: a PTC resettable fuse. The PTC standes for Positive Temperature Coefficient. In brief these parts are designed to melt and break the connection like any fuse if they are getting too much …

This is a monostable multivibrator circuit, or “one shot”. The diference between a monostable and astable multivibrator is that the monostable vibrator has a default or preferred state from which it can be jostled for a only a set period of time. …

Like June 19th, this is kind of preboard as it is it does nothing that can be seen easily and the pins are not the most accesible. My plan is to do one with LEDs for tomorrow. I’m a bit embarrassed to say I already have two favorite sites with mul…

Roughly the same schematic as yesterday with an extra header for a ground pin next to the signal pin in case the (regulated 5V) power supply for this circuit is different than the 5V for the Arduino. I wanted to make the board smaller, since audio…

Doh. Missed the cut off by a tinsy bit to go see Submarine directed by Richard Ayoade of “The IT Crowd” fame. Totally worth it. More on this one in the future… it’s a combo of the standard ITP version and some other circuits. To see the Physical…

So a quick, last minute, right before midnight post today. I needed a way to put indicators on schematics for objects that really only appear on boards. I’ve created a system with items in rectangles for objects destined for Document Layer (48) an…

One of the things that has been taking up some time in making these posts is preparing the final images for the top of the post with my name, the license, etc. I’m hoping creating frames will help with documenting these things in the long run. The…

I’m trying to make my Eagle time more effective so today I’ve spend some time setting up the environment. Required reading? Eagle FAQ, Section 6: “Where and How to Configure EAGLE?” http://www.cadsoft.de/faq.htm#06011304 Eagle Help Files: Configur…

I think I’m going to need two days on these boards to feel final about them. I’d like to really explain the circuit, pick some better values for the resistors and the capacitors, import the parts into my library, check the spacings on the headers….