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Subject: Re: [Homebrew_PCBs] Re: UV light sources question

From: Stefan Trethan <stefan_trethan@...>
Date: 2004-01-21

On Wed, 21 Jan 2004 06:37:37 -0000, Ben H. Lanmon <bhleavi@...>
wrote:

> The tubes that I am using are Black Lite, when I got them at a
> lighting dist. I had asked for these with out the blue filter which
> was what M.G. Chemicals had recommended using but after I picked
> them up and got home with them found that they had sold me tubes
> with the blue filter. I tried them and worked OK so here I am some
> 10 years later and still using them. They are a Sylvania
> Blacklight Blue F15T8/BLB I use (4) of these at a distance of
> about 7" for about 5 to 6 mins. I normally do boards 12" x 8" or
> 10" x 8" in size and using the M.G. Chemicals 600 series boards.
>
> Ben
>

i think with the proper tubes (4 at 7") you should have 30s.
i am sure about that, because i used such a unit some time ago.
i'm sorry but i can no longer look for the type of tubes and didn't then.
the board was bungard i think, but standard sensitivity (no darkroom or so
required).
I suspect it must be short-wavelength UV.
this has more energy by itself, maybe also the resist is more sensitive.
the "black light" tubes are, as said before, long wave uv (to protect the
eyes).

ST