Board Layout for Don Clement's Dew Heater Compensation Circuit
This page is linked off of the page detailing the ciruit and it's operation. If you got here by some other means and need some help, navigate up one directory for more details on Don Clement's circuit diagram and ananlysis.
I used a free Linux program called PCB ( http://bach.ece.jhu.edu/~haceaton/pcb/ ) to layout this circuit.
The whole board is only about two inches square so it is difficult to see the numbers on the silk screen view. The board is even a little less crowded than this diagram indicates. The library is a little sparse so I calculated the positions for the variable resistor R3 and put in vias to represent where the legs go. I added the words "SOLDER SIDE" to the trace mask to avoid confusion on which side is up. (The bottom tool bar is from Gnome Desktop and unrelated to the program)
Study the schematic from Don's page carefully before starting.
This is a simple circuit and shouldn't be to hard, even for
novices.
Larger screen shot here
Since the circuit is under 2 inches square and several are being made, six were put on one board. This way control can be centralized or individual boards can be sawed off.
The trace mask for a single board is here.
The
trace mask for a 'six pack' is here.
I was reminded that post script isn't a 'customary' file type for
a certain widely used OS:
"Here's the link to ghostscript
and gsview, too.... for us windows weenies.
http://www.cs.wisc.edu/~ghost/index.htm "
Ghostview should allow you to print out the mask 'actual' size so that you can use it to etch your circuit board.
I have built one prototype board so far and it functions. Since this was a group project, the electronic components were under $8 US per board. Digi-Key should have everything you need. Jameco has better prices on some of the components but didn't have everything. The savings on 12 units was more than enough to make up for the extra shipping charges for ordering from two places in my case.
Once I get one of the regular boards built, I'll add a picture. The prototype had the traces etched on the wrong side which made soldering a night mare. It is functional but not very photogenic. ;-)