I think I mentioned that laying out the schematic into Express PCB
took the most time to learn, mainly because you have to add your own "custom"
components so they don't cramp each other and leave sufficient room between each other
on the board. I think all builders should do this because available/on-hand components
are different sizes.
When I run out of these .001uF or .01uF capacitors, I'll have to
check the board layout again for fit. Your advice: 'stand all the components upright'
made everything a little easier. Transfering and etching the boards was also a new
experience. There are a million small things to learn (i.e. when ironing, don't press
down too hard on the transfer paper--it doesn't help and smears the traces). Let your
readears know not to get discouraged. I made 4 transfers to copper PCB before I got one
good one. I've also lost boards in the etching process when traces weren't dense
enough. Tough. Do it again.
I will eventually try to get all of my electronics to fit into a
"professional" looking enclosure. The attached image is a nice box sold by
Memotronics(4.4"x2.2"x0.8"). It's small enough to
fit 9V batteries, but I think my next transmitter will use the 4x AAA battery box since
it also fits nicely and the transmitter will last longer. The boxes are also cheap at
One last piece of advice to builders: my best supplier is
Small Parts and Kits. He has almost everything to
complete these projects in stock. Amazingly, Dan also answers the phone when you
Footnote: From John
Regarding the frustration mentioned above when someone initially
starts out with the "Press and Peel" method of making their circuit boards, let me
relate the method that I prefected years ago. First of all, go to your nearest flea
market and purchase three or four of the old type flat irons - without the steam holes.
Next plug them in one at a time - set to medium and use a temp gage and pick the iron
that has the most continual heat range over the entire flat surface.
Next, you will need to make a Master Board out of 3/4 Plywood about
a foot square. Make sure it is flat and smooth. This is the board where you will iron
on your transfers. Next, prepare your copper board by using "Very Fine" steel wool and
clean off the copper side of the board since it will have a thin film on the copper
which happens when it is laying around. If you don't do this, your track lines and
circles will be spotty and an overall crappy board. After you have cleaned the copper
side, wash it using cascade or regular dish washing soap and it will come out sparkling
clean. Then dry it with a soft kitchen paper towel.
Next, lay the copper board down onto the plywood and place your film
over the copper. You never want the iron to come in direct contact with the film
transfer - so place a regular piece of computer paper 8x10 directly over the film. Next
set your iron to medium heat and let it warm up for a few minutes. Next, start ironing
on the transfer ( computer paper over the transfer ) and use a smooth, continual
pressure and iron in a circular motion rather than back and forth, etc.
Timing is everything so write down how long you spent, ie, 5 minutes
etc. the temp range on your iron, etc. until your boards come out perfect. I have used
this method for over 20 years and have always made perfect boards.
I usually make 5 to10 boards at a time and below I have shown an
image from my last "Iron On" and filtered out everything but the layout itself to give
you an idea of what my copper board looks like before I drop it into the Etchant tank.
This particular board is my master for the XMT Transmitter shown on this site. It is
100% SMD ( Surface Mount ). Regarding "Standing the parts straight up", that makes for
a smaller board.
I furthur reduced the size of my SMD Boards by standing all of my
SMD components on edge, similar to razor blades rather than flat.