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Message

4th board 99.9% perfect - thanks for the input!

2003-01-01 by ghidera2000 <ghidera2000@yahoo.com>

My third board was a flop. My plexi weight had a slight curve in it 
and I didn't notice - lost the traces in the center during 
development. For the fourth I used the curve to my advantage and 
propped up the sides with my first two (discarded) boards.

I also changed from the MG boards to a different brand. No choice, 
store didn't have MG. This one claimed 60 second exposure with a UV 
source and 6-8 minutes with a florescent. I thought my UV florescent 
would qualify as a UV source - it doesn't (silly me :D) Exposed for 
60 seconds and tossed it into the developer. Sat there for two 
minutes with zero effect. I rinsed it off and re-exposed for 6 
minutes (board is gone, may as well experiment). Developed in like 1 
minute and it was PERFECT. Couldn't believe it. I expected to see a 
ghost of the first exposure but there was none at all.

Tossed it into the etcher and it came out almost perfect. No shorts 
at all despite using a bunch of 1.2 mil traces spaced 25 mil apart 
(center to center). There is one trace that has a tiny spot which is 
about half the width its supposed to be. Can barely see it with the 
naked eye (I'll hit it with a tiny dab of conductive pen). I'm 
thinking I probably lost a bit of resist during the first developer 
foray. Hopefully my circuits are correct and this one works. They 
work fine on the breadboard and I looked them over (and over, and 
over) before I even did the first printing. If it does then I have a 
week or two of schematics and breadboarding before I etch my pH and 
ORP controller for my swimming pool.

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