Homebrew PCBs

On 3/18/2016 10:36 PM, 'Brad' unclefalter@... [Homebrew_PCBs] wrote:
> <snip>

> I\u2019m wondering \u2013 what differs in etching with double sided projects?  
> And when they say the holes weren\u2019t plated through, does it mean what 
> I think it means (there would be a copper connection between a trace 
> on one side through a hole the component is soldered into through to 
> the other side?).  Not sure I\u2019m understanding how the connections 
> would be made from one side to the other.
>
Hello--

One process used in the 1970s involved drilling holes through a 
double-sided copperclad board, followed by an
electroplating process that deposited copper on the insides of the 
holes. The board was then coated with resist,
exposed, developed and etched. Removal of the remaining resist exposed 
the plated-through holes (vias)
for component insertion. (I've omitted several intermediate steps for 
brevity.)

Homemade double-sided boards rely on using components' leads as the 
vias, but you need to solder the components'
leads on both sides of the board to ensure continuity.

73--

Brad  AA1IP