Noise Blanker recovery time constant for digital modes

Keith - KE4TH

NB delay.PNG

I use my Flex 6500 for meteor scatter (wsjt-x msk144 mode) on the 6m band.  Running DIGU mode on the radio I have to use the noise blanker due to local noise in some directions.  The noise blanker takes about 5 seconds to return to normal level at the start of each 15sec transmit cycle.  This means the radio is mostly deaf for one third of each listening window.  Please see screen grab above.  If the user is allowed to adjust the NB recovery time constant, this dead time could be reduced or nearly eliminated.  Please make NB recovery time constant a user-adjustable parameter.  Thanks so much for listening!  73, Keith - KE4TH

Mike-VA3MW

This is for the WNB?

cfclaver

Mike,

This is for the "regular" noise blanker - NB. I have the same slow recovery issue when operating not just with digital modes but also with weak signals on CW and or SSB. The NB is very slow to recover after transmitting, significantly reducing sensitivity for several seconds. For weak signal SSB and CW the NB is often not effective overall because of the slow recovery.

Back in the day with my 5000a and PowerSDR we could get into the parameters of the NB and fiddle with recovery time constant to find the best settings for the mode and conditions.

73s,

Chuck
de NJ6D

W8TZ Ross

Same issue with SmartSDR v2.12.1 and Flex 6400M