> -----Original Message-----
> From: Leon Heller [mailto:leon.heller@...]
> Sent: 25 September 2006 16:27
> To: Homebrew_PCBs@yahoogroups.com
> Subject: Re: [Homebrew_PCBs] UV Light Sources
> >operating. Can any one confirm that this is comparable or
> better than the
> >black-light fluorescent approach?
>
> It's a lot better (much shorter expoosure), but needs to be a
> long way from
> the PCB/artwork for good collimation (something like 1 m,
> IIRC). I've got
> some similar sodium lamps that can have the outer envelope
> removed. The
> ballasts can be difficult to find. For accurate exposure I
> think you need
> some sort of shutter arrangement as they take some time to warm up.
>
> Leon
Thanks Leon
For the collimation I was going to use a parabolic reflector. With a 16" (400mm) dia., reflector it would seem to be feasible to have a working exposure area of 12" to 18" (300 to 400mm) Instead of a shutter I was thinking of using a slide-in frame holder. In OZ we can get 250 watt self ballasting globes the run off our 240 volt mains supply. This set-up would be far less expensive than say 4 or 5 fluro tubes plus their associated ballasts, starters etc (at least in the antipodes).
Regards
John C