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
| 