Monday, November 18, 2013

And a bit more...............................

The voltmeters I ordered from China have just arrived and they are lovely little toys. Very small, not much bigger than the display alone, and only two wire connection. They operate on any voltage from 2.5V to 30V and just work. They cost me 99 pence each and are brilliant. I intend to couple them with one of my homebrew mains power supplies and a DC-DC converter to make up some very useful variable power boxes for my various projects.

Monday, November 4, 2013

PIRfec'

As pop Larkin never said. The board arrived on Saturday and I cobbled together a quick test that very evening. It worked first time. Now I want to build a small unit to mount above the bedroom door to switch on a couple of LEDs to light our way to the bathroom at night. I will document.
This is a very small item and costs very little. I bought one for £2.54 and it's possible to buy a pack of ten from China for even less per item. Just check out eBay.
What is it? It's a very small PIR (infra red motion detector) that interfaces directly to an Arduino and can trigger an action. In this instance, I want it to turn on a couple of white LEDs for a short period.

Kardoma:

fills the stage with flags!
Free counters!