In a private email to me, the original questioner, Rick, N6PE, said
that his First Alert units are battery operated, stand-alone. I'd
say the best course of action here is the one that NY9H took --
replace them with units that don't have RFI problems. It simply
isn't worth the trouble to fix them. And be sure to take the bad
ones back to the store and demand a refund.
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