I still notice some random FM noise that breaks thru the squelch in SSDR 1.5.

Roy Laufer

Well, the title says it all. Does anyone else notice the same intermittent breakthru's of noise breaking whatever squelch setting I use?

I had hoped SSDR 1.5 would have dealt with this...

Perhaps SSDR 1.6 will solve that <grin>?

73,
Roy AC2GS

Jim Gilliam

I am not sure what you are saying...Are there noise bursts that fall within the pass band of the radio that are equal or greater to the squelch threshold or are their random bursts that are self-generated by the radio causing the squelch to open. It would seem that if the noise is NOT generated by the SDR, the opening of the squelch would be a perfectly normal reaction.

Jim, K6QE

Tim - W4TME

We have a bug report listed for this issue.  It is not slated to be addressed in SmartSDR v1.6

Roy Laufer

Offhand, I can't tell you if the noise is external or internal. It just seems to me that no matter how high I set the squelch level, there is an intermittent breakthrough noise that I don't find on my old IC-7100. I doubt that the background noise it transiently disabling the squelch.

It seems like a small problem with SSDR's squelch algorithm...

Jim Gilliam

I would guess the SDR squelch is amplitude sensitive while that of the 7100 is both amplitude and energy dependent. I guess they will need to incorporate some time of time requirement of the burst to emulate that of the 7100 characteristics.

Jim

Cal N3CAL

I've noticed this on my Flex-6300 with my Elecraft XV-144 transverter on 2 meters.

Cal/N3CAL

Norm - W7CK

Try using the squelch control in FRSTACK.  It works in several modes and each slice is individually controlled.   Its under the Radio tab and is labeled as "SSB/AM Meter Level Control".   Works wonderfully.

Ken - NM9P

Is the FM squelch a noise-based squelch or a signal level squelch? If based upon noise, perhaps some averaging could be applied to even out the noise before detection to eliminate sudden changes?

Jim Gilliam

That is known in the mathematical world as integration with respect to time and dividing by the element of the change of time yielding the average. However there is one more element to the equation and that is the peak level. Not only do you want a certain amount of average energy but you also want to trigger on a peak value. When noise is in the pass band of the receiver other than the randomness, both voice and noise are very hard to differentiate.