[BC] resolving harmonic IM issues.

[warren.shulz at citcomm.com]

Mike,

That is a great story about tracking down inference.  Thanks for posting
this.  As you suggest being combative does not solve the problem and the
process is a very linear set of steps to mitigate interference.
Pointing fingers is not on of the steps if you know what I mean....

Warren Shulz
WLS CGO

-----Original Message-----
From: Mike McCarthy

Finally, I called the studios and had the operator switch to the much
lower power back-up SITE some 15 miles away. (Why not just do it and not
bother staff you ask???...Simple. I want the staff operators to practice
this procedure...) Then shut power off to the 816 insuring that all RF
generation was terminated.

After shutting down the site, I asked the tech if he still showed the
problem. He said nothing changed.  His pilot channel was still being
hammered. I then waved him over to our building and showed a completely
quiecsent transmitter. Kodak momment.

I received a call a few days later from the tech and the shop foreman
advising they have egg on their face. Turns out it was a cell site a
mile
away emitting stuff on a channel outside their passband.  I told them no
problem.  It's an easy mistake to make when one starts debugging IX.