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Phil Allison[_3_] Phil Allison[_3_] is offline
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Default Selectivity vs. sensitivity

wrote:


"Tuners that are beloved of the "FM DX" crowd will tend to have: "



I want one with continuously variable IF bandwidth on the front.



** Such a feature is useful with AM reception but not with broadcast FM.

The FM signal is inherently wide band, with +/-75 kHz deviation at peak audio level - if the IF bandwidth is less than 150kHz, distorted sound is the result.

I have a radio scanner ( AR 1000xlt ) with wide and narrow FM modes, 30kHz and 200kHz respectively. Listening to broadcast FM while in narrow mode is *intolerable*, in wide mode it sounds just fine.



..... Phil