[BC] The K-Word

[jmjpcc at bellsouth.net]

Andrew Skotdal wrote:
>Anyone on this list have specific experience with using a PowerSide on a 
>directional AM station to improve coverage in nulls?

I have found that with Power-Side there is no change in field intensity in nulls.  However, a station becomes more "listenable" with Power-Side in the chain.  I believe it is that with symmetrical sidebands there can be sideband cancellation as a result of scatter and re-radiation. Because Power-Side produces asymmetrical sidebands, there cannot be as much cancellation.  I was involved with the installation of Power-Side at four stations, and saw the same results each time. One DA-2 station with had a very deep nighttime null (.15 mV/m at a point three miles from the 50KW transmitter).  Driving to the point, I could always tell the point was "in" by the fact that the station became unintelligible on the car radio.  After the installation of Power-Side, approaching the point made the radio a little more noisy, but fully listenable, and the point was still .15 mV/m.

The biggest negative about Power-Side is that there can be no audio clipping ahead of the Power-Side unit.  This means you have to back off the clippers in the processing, and take a bad hit in loudness.  Kahn has clippers in the output, but they are very harsh.  I have experimented with using a limiter/clipper at the "insert" point with mixed results.