Homebrew PCBs

> -----Original Message-----
> From: Leon Heller [mailto:leon.heller@bulldoghome.com]
> 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