--- 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
