Yet another Armor Idea

I have been thinking about the armor works, especially after seeing how unfair
it was in a battle I played last weekend(and I was the one using it.)
Basically, armor is not anything new for humans. If it was so cheap in terms
of trade offs, why wouldn't humans use it? They would use it unless there was
a really good reason not to. I propose radiation damage. My variant has beam
weapons having a chance to do damage like an EMP missile to unshielded
targets. To determine if extra damage is done, look at the
_unmodified_ die roll damage from beams.  For each _ten_ points of
damage
that _would_ have happened to a ship without armor, each internal system
must make a threshold roll of "6" or have it's circuits fused. I'm going to do
some more playtesting this weekend but I would appreciate any feed back.
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