I had been thinking of controlling my room lighting using my computer. I
bought some triacs and opto couplers to do this. I drew the schematic and built
a prototype. Everything worked well.
When I was wondering in which case to use, one of my friends suggested
that I could use my computer switch box.
Here is what the switch box looks like:
Here's some pictures showing how it is built:
We cannot see it on the pictures, but there is a cable going out of the box that
plugs in the PC parallel port. The small grey box on the leftmost picture
contains a 7805 and a 76ls06 to driver the opto couplers.
Schematic and PCB
If you want to build one, here is the schematic:
I used L2008L6 triacs. If you need the circuit to work with 220 Volts, you'll
have to choose another type of triac, like the L6008L6. Here is the
datasheet of the triacs I used.
The opto-triacs part number is TLP160G. Here is the
Use this only to driver ordinary lights, or other resistive loads. Dont use
it for inductive loads, such as motors, or halogene lights which uses transformers.
Dont forget to power the 7406!
The pull-down resistors (at the inverters input) are there to make sure the lights stays
off when the interface is disconnected from the parallel port.
You can add leds showing which outputs are active. Do it like this:
I know someone who uses the following software to control his interface.
It is a plugin for winamp named discolitez.
What I like to do with this interface is to make the lights follow the music. To
do this under Linux, there is an xmms plugin named palace. The latest
version is available on this site:
Here is a small clip of the interface working with palace (925 Ko):
And a screenshot of palace:
I cannot be held responsible for any damages that could occur to you
or your equipment while following the procedures present on this page.
Also, I GIVE ABSOLUTELY NO WARRANTY on the correctness and usability
of the informations on this page. Please note, however, that the procedures
above have worked in my case without any damages or problems.