Homebrew PCBs

Adam Seychell <a_seychell@...> writes:
> For calibration, you just take a strip of pre-sensitised PCB, and
> expose it in increments of 10 seconds.

Or just expose it with a step gauge and read the step number.  The
film says what step number it needs, just expose once and adjust the
exposure according to the step number.  For $7 it doesn't pay to do it
the hard way.