It is getting so easy to order a finished printed circuit board that it is tough to justify building your own. But sometimes you really need a board right now. Or maybe you need a lot of fast ...

Earlier this year [Skyhawkson] got ahold of an Apollo-era printed circuit board which he believes was used in a NASA test stand. He took high quality photos of both sides of the board and ...

The two diagrams above are of the same circuit for a simple night light. How it works: when darkness falls on the light dependant resistor (LDR), its resistance increases causing a higher voltage ...