[BC] AM transmitter lightning sensitivity issue

[radioranger]

I had a similar situation about 10 years ago with a Gates 1, except no fold
back--- just a blown FET to protect each fuse everytime lightining got
within 10 miles of the 3 tower DA.  We got all the info Nautel has available
concerning protecting the transmitter and installed:

a.  ferrite donuts on all incoming transmission and sample lines
b.  Jacobs ladder type horn gaps right inside each ATU
c.  good AC power line surge protection
d.  readjusted ball gaps at tower bases
e.  4 20 foot ground rods at each tower, spaced about 20 feet out from the
tower base and cad welded to the tower base via welding cables.  The Nautel
belief is that the RF ground system typically installed at a tower base
isn't a very good lightning ground.

I can't tell you which of these or all of these did the trick, but I can
tell you that after these fixes were applied the transmitter is rock solid,
and last I heard hasn't blown a FET or fuse since.

Steve Brown
Radio Rangers, Minneapolis