![\"20131029-094044.jpg\"](\"http:\/\/www.vk2sja.org\/piffle\/wp-content\/uploads\/2013\/10\/20131029-094044.jpg\")
<\/a><\/p>\nNow I wish I could properly credit where the original idea came from (It was not mine) but it was so long ago I’ve forgotten which Journal I was reading. Perhaps GQRP Sprat or maybe even VK-QRP Lo-Key.<\/p>\n
Anyway, I finally found some copper foil. The like of which I think was being referred to in the original article. I found it on eBay (where else) and ordered a small roll. I gather it’s intended purpose is for creating RF shielding for enclosures.<\/p>\n
The blurred image above (Sorry, I’ll take some better photo’s later) shows the result. A paper hole punch for creating confetti dots was used to punch out some pads. Three dots were then stuck to a white sticky label on top of the PCB. Then a transistor was soldered to the dots.<\/p>\n
So “Yes”, it works.<\/p>\n
Is it quick and easy? So much so that I won’t be picking up my Dremel again? No, not yet. At least not without some refinement. The cheap hole punch causes the foil to buckle. A more expensive two-hole punch works fine but you can’t easily see to properly align the holes your punching. So you end up with a lot of wastage. Of course it is dead easy to cut odd-shaped rectangles with a pair of scissors.<\/p>\n
Even the act of removing the backing tape from the “dot” and sticking it down is fiddly and somewhat time consuming.<\/p>\n
I also worry about the stray capacitance between the copper foil sticker and the copper sheet of the PCB proper. The two being separated only by the width of a paper sicker. Stray capacitance could get quite high here.<\/p>\n
But with some refinement the technique shows obvious promise. So while the Dremel may not be due for retirement any time soon I can see a “hybrid’ construction technique developing. <\/p>\n
Utopia would be a box of 500 easily dispensed white paper dots, each containing three little copper dots.<\/p>\n
Anyway, I’ll keep playing with the idea.<\/p>\n","protected":false},"excerpt":{"rendered":"
Some time back I read about an Amateur who had discovered a copper foil with an adhesive backing. He was experimenting with using it for PCB construction. At the time I thought;- “I must try that”. It took quite some … Continue reading