Homebrew PCBs

I hate it when people think ... Wow, great idea Myc.

Just offsetting each row by half the grid would probably be a lot more
even.  It may not matter a lot but, it's really easy to do it so why not?

I'm going to try building one of these myself.  Looks like a great
idea and would make the photo process one step easier.


btw - the UV diodes have about a 3.3v drop on them.  That's why 3 per
line on 12v works good.  But 4 would work well off a filtered 12v
transformer and 8 off of a 24v one.  I plan to run rows of 8 to keep
the current demand on the power supply down (and as mentioned, all
diodes in each group of 8 will have the same current ... nice and
easy). 12 rows of 8 would only be a 1/4 amp.

You get about 17v off the 12v when filtered and 34 off the 24. Enough
to regulated to 30v and then a small resistor for the current limit
... something around 150 to 180 ohms for the 20mA and well under 1/10
W.  The regulator might be overkill but helps make for nice clean DC.

Phil



--- In Homebrew_PCBs@yahoogroups.com, "Myc Holmes" <mycroft2152y@...>
wrote:
>
> All of the designs so fr have used a rectangular grid. Since the
output is
> circular in shape, why not take a clue form the honey bees and set
up the
> LEDS in a hexagonal grid? This should result in more even coverage.
> 
> Myc