Hello Dale,
Saturday, February 24, 2007, 5:10:28 AM, you wrote:
> Sunlight.
Nonconstant UV-A radiation on hourly basis.
> Short wavelength UV doesn't pass through glass very well. The good UV
> bulbs are made of quartz, hence they're kinda pricey.
Short UV has nothing to do with photoresist on copperclad. Peak
sensitivity of photoresist is somewhere around 340nm what stands for
'long wave UV' aka UV-A.
> I've done boards in sunlight with some success. The trouble is, the
> amount of UV you get from the sun varies widely from day to day and I
> think humidity eats it up.
For my prototypes I use Philips UV tubes for reprography. they are
marked 'somethinginhere/05N'. Won't harm your eyes, and this
wavelength of UV is passing ordinary window glass. I'm using 6mm
(1/4") piece as it is heavy enough to make enough pressure to my
repro films or vellum.
--
Best regards,
Zoran A. Scepanovic
zastos@...∗∗∗∗∗∗∗∗∗
When working toward the solution of a problem, it always helps if you know the answer.
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Please be advised what was said may be absolutely wrong,
and hereby this disclaimer follows.
I reserve the right to be wrong and admit it in front of the entire world.
Local time: 08:31
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