Like you , I have both CW filters and use these regularly...... the NR function at times seems to not work as well although the rig is as close to perfect as you can get for both CW and digital
John VE5MU ----- Original Message ----- From: mulveyraa2 To: [email protected] Sent: Tuesday, January 09, 2007 6:29 PM Subject: [digitalradio] Re: Random thoughts on digital operating... --- In [email protected], "John Bradley" <[EMAIL PROTECTED]> w > I regularly use the rig's filters to enhance the signal quality at my end. one thing I haven't got my head around yet are the noise blankers and noise reduction devices, which seem to have an adverse effect on the quality of some signals. Being technically challenged I don't understand that........... > Are you using the mechanical filters, the DSP filters, or both? Particularly for digital modes, the mechanical filters will make a world of difference, since they'll be reducing the passband width - a necessity in crowded conditions, or when a strong station is causing the AGC to pump. The NR/NB/DNL filters are all DSP based. As such, they're modifying the audio signal. Some of the processing they do is incompatible with some digital modes - they'll start changing phase, etc. That being said, there are cases where the NR1 noise reducer will help with signals on a noisy band. NR2 is strictly for CW, and will make any digital signal unusable. DNL is essentially a Noise Blanker on steroids, and will often work when NB won't - but it also has more negative effects on the audio signal. I've found that they all work best when I've also got a mechanical filter in line. - Rich
