I beg to differ on this one, most respectfully, but we are talking about the difference between running the transmitter at 2.5 Khz deviation vs 5.0 Khz, ie, 12.5 Khz occupied band width, vs, 25 khz occupied band width - does this mean a duplexer retune is needed when we switch from narrow FM to wide FM in modulation ? I will concede that the depth in notch is much more dramatic than the change in pass band, and if the system is marginal to begin with, it might make a difference, but for the most part, moving 12.5 Khz would not be noticeable in performance. Of course, there is no harm in re-tuning (I hope)... 73,
Steve NU5D skipp025 wrote: > Hi Paul, > > I go the other way where multiple Duplexer High-Q Series Cavities > have a deep sharp reject notch and a 12.5 KHz shift from F-center > results in a quite noticeable performance change. > > cheers, > s. > > >