[TZ] Third order intermod in FM Station

[robertm]

800 kilohertz separation is quite common in many markets. Any number of manufacturers can build a combiner with proper filtration.  I would suggest that approach as opposed to separate antennas.You said the 10 KW was slant polarized which implies dipoles which should have enough bandwidth to handle the bandwidth. The 1 KW will require less transmitter. 

You really need to use a spectrum analyzer to determine the existence of IM. A simple radio could overload and therefore be misleading. 


> On Sep 10, 2017, at 1:32 PM, Rolf Sandmeier via Tech-Zone <tech-zone at radiolists.net> wrote:
> 
> 
> We hastily mounted the new system, and the test results were positive for IM above my expectations, worsened by the fact that the station stays in downtown commercial center. We took a drive around and the 93.7 came loud and clear up to 1.5 mi in line of sight of the tower , whereas the 91.3 faded away within few hundred yards.