chpalmer wrote:
No. If you are trying to transmit more than one carrier through an amp then yes it would take up those resources. (IE spurs, broadband noise) A preamp on a recieve antenna would work the same way. The more it has to amplify, the less good it will do your intended frequency.
In fact the narrower you go the less coverage you should have due to SNR.
I have been a little impressed with the audio qualities of the Motorola CDM series with 12.5kc channels but the receiver is still pretty wide so adjacent channels still are a problem...
There is another take on this though.
"Extreme" narrow modes (> 6.25KHz channel width) are typically digital modes. Digital modes offer higher clarity at the further reaches of coverage areas when compared to similar range analog systems.
I have some customers who feel therefore that the digital range is "better". In reality the audio is clear all the way to the far end of the range, but then it drops off, just like a cell phone.