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January 1997

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Subject:
Re: Unidentified subject!
From:
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Date:
Wed, 22 Jan 1997 07:42:41 -0500 (EST)
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<<       OK, Here's a quick and dirty way to find out moisture 
           content:
           
           1.   Measure the PWB then weigh it.
           2.   Bake the PWB for 24 hours at 250 deg F.
           3.   Weigh the PWB again.
           
           The difference between the weights divided by the area (or 
           volume) of the PWB will give you the moisture content.  
           Baking above the boiling point of water will drive off 
           moisture, and 24 hours is a good amount of time to drive off 
           enough moisture to give you a realistic number.
            >>

The only thing that I would add is not to weigh the board while it is hot
(weight will vary as it cools) and to allow the board to cool to room
temperature in a dessicator.  Hot laminate will immediately absorb some water
from the atmosphere.  

Doug Pauls

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