Date: Wed, 27 Jul 2011 14:53:17 -0400
To: rsgb_lf_group@blacksheep.org
From: Bill de Carle <ve2iq@magma.ca>
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Subject: Re: LF: Re: Lightning Story
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At 02:34 PM 7/27/2011, Alan G3NYK wrote:

[..]
>You didnt say whether your op-amps were powered? ..... I suspect not but the
>generation of a large voltage across the loop might be enough to to lift the
>input to a destructive level, and decoupling caps can store a lot of charge.

Both the mini-whip and the loop preamp are normally battery powered 
but were not powered up (not even DC grounded) when the lightning 
hit.  It was clear that a large current flowed through the IC but 
from where to where?  I suppose the two big series-connected loops on 
the amp's input could have formed a capacitor to ground for high 
frequency components but I don't see any sign of arcing across the 
coupling transformer at the shack end of the cable.  And none of the 
passive components in the preamp was damaged.

Bill