Tuesday, November 18, 2014

passive infrared power switch.

So,  a few parts
an Arduino
a micro display
a passive infrared sensor
a relay
a power outlet
and a box...

and some code....  

and oh by the way... what happens when you sprintf 11 characters into a char[10]?  the arduino resets.


seems functional... let's put it on a board..

small wiring...

and a box...

oh wait... how do we power the thing... it doesn't work so well when you plug the arduino into the switched outlet...

this ought to do..

looks good...

and mounting it up..


and buttoned up.

Sunday, October 19, 2014

Temp sensor

Hey Q.  Here's an easy one for the Nerdlings...

An embedded processor, a ds1821, and a display.

I have spare parts if they are interested..

Wednesday, October 15, 2014


And Joel has gotten hit twice now from the capacitor..  330V is pretty good...


switched out recently from the Arduino Uno to the Nano (v3.0)

easier to fit into things and if I build an actual custom PCB then I can mount the arduino directly.  and since I know someone with a CNC mill for just such PCB creation, I should be set...  

what is that other thing the orange wire is plugged into?  its a DS1821 temperature sensor.  pretty cool little device.

An Extremely Terrible Misfortune


A terrible misfortune happened (to someone else) and the single copy of their important data was on a flash drive.   It was plugged into the computer when said laptop decided to challenge the law of gravity.

The flash drive lost..

and so the soldering iron came out and I managed to recover the data...

and the moral of the story is...   Backup your data...  a single copy on a flash drive isn't safe.

FM transmitter


Hey Nerdlings!!   Here is your project...

Hmm... I need an oscillator

and I have an arduino and an extra AD9850 setting around...

so the theory seems to work just fine.  now we need to control and report...  so some user interface work,   a rotary encoder, a switch, a 10k trimmer and a box later and...

It's Dead Jim.... no, It's alive

My poor radio needed a back-end Amp replacement.  seems a couple of the transistors had died..

so, after some work, it's alive again..

Build a Tape Measure

So, I have an Arduino and a spare ultrasonic and some displays... what to do.   Oh... a tape measure.

Build an Antenna Analyzer

So I was looking for a way to get some antenna's (or is it antennae?) up on my roof for my radio.

In order to get them built, I need an analyzer.   Being a good engineer, don't invent things that already exist and I found Luca's kit.  

The workspace

the nearly finished product.

and it's alive!!