Wes, The DSP NB causes some artifacts at its higher settings. This is an unavoidable side effect of signal processing.
The DSP NB is applied after the crystal filter, so the bandwidth is already constrained, removing some of the inherent characteristics of noise pulses, including their rise/fall time and shape. Thus it is harder for the DSP to distinguish between signal and noise. On the other hand, this is the only way to remove narrow-band noise (e.g., noise that appears every 10-15 kHz on a particular band, rather than blanketing the entire band). The DSP NB also has the advantage of not being "pumped" by distant signals outside the crystal filter. The IF NB has the opposite situation to contend with. Noise pulse shape and rise/fall time are preserved, so they can be effectively gated. But if you set the threshold too low, the IF NB's noise gate can be modulated by very strong adjacent signals. By including both, we give the operator the ability to optimize the ratio between IF and DSP blanking, which can be extremely effected as attested to by many customers. 73, Wayne N6KR Wes Stewart wrote: > Thanks Merv, > > So it isn't my imagination as some have inferred. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
