I'd like to build a 2 watt power meter for RGB (400-700nm). I could build the electronics myself probably. I kinda like the one Steve Roberts had at SELEM with the analog meter. Kind of old-school-nostalgic Does anybody know what they use for the head/ sensor in those things?
And possibly any circuitry/ schematics? (I'm not asking much, am i)
Thanks in advance all,
Steve