Homebrew PCBs

On Wed, 14 Jul 2004 00:47:14 -0000, Esteban <earias@...> wrote:

> Hi,
>
> Finally I upload a photo ("Esteban" Folder in photos section)of my
> pcb with toner transfer method.
>
> Thanks to the Stefan Trethan aid, I build a thermostat circuit for my
> HP 4L laser printer fuser.
>
> I am using only free catalog magazine paper.
>
> One more time; thanks Stefan for your help.
>
> Greeting from Chile
> (sorry by my english).
>
> Esteban Arias
> earias@...

nice board, clean work.
You might also want to try out component legend with toner transfer,
it is easy to do and really rewarding.

I'm glad i could help, and I'm glad you took the little help, added a good
amount of effort and work, and got a very good result.

I think i will set up a page publishing that temperature controller 
circuit.
It would be better to add integrating and rate components to make a PID 
controller
but i think it is hard to adjust for beginners. The simple circuit 
oscillates slightly
but the temperature does stay within my measuring resolution.
Maybe i'll add very low hysteresis to keep it from "free" oscillating.
As it is syncronous to the mains frequency it isn't really a problem.

Esteban, i would very appreciate discussing the performance of the 
thermostat on your
fuser. I think you have a ceramic heater and can't see when it's on? 
perhaps
you could connect a test lamp or something parallel to the heater.
What i'm curious about is if it is oscillating slowly or not.
We can discuss this off list i think.


ST