Tone oscillator with APF slider 2...6

  • 1
  • Problem
  • Updated 4 years ago
  • Acknowledged
Ver 1.4, in CW mode when APF on, and APF slider between 2 and 6, generating parasitic tone
F6700
Win10 Technical Preview
Photo of Sergey, R5AU

Sergey, R5AU

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Posted 4 years ago

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Photo of Paul Christensen, W9AC

Paul Christensen, W9AC, Elmer

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Yes, I can confirm Sergey's finding on APF. 

Paul, W9AC

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Tim - W4TME, Customer Experience Manager

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Official Response
I have enter this report into our bug tracker for further investigation.  Please report any additional information related to this specific issue in this community topic.
Photo of Rick Hadley - W0FG

Rick Hadley - W0FG

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Aside from the above problem, which I have also observed, the APF also doesn't seem to increase in effectiveness as the slider is advanced past the point where the parasitic stops.
Photo of Steve N4LQ

Steve N4LQ

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Same here with WIN 8 but 4 and 6 are just dead audio while 2, 3 and 5 are tones. 
Actually the tone could come in handy as a spotter. Maybe ...Click once for APF and twice for tone? 
Photo of Al / NN4ZZ

Al / NN4ZZ

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Sergey,
Here is what I'm seeing on a 6700 and Win7

APF = 1  it appears to be working and helps pull out the CW Signal
APF = 2 tone
APF = 3 tone
APF = 4 dead, no audio
APF = 5 tone
APF = 6 dead no audio
APF = 7 thru 100 signal reappears but APF is not longer effective.  Sounds the same on or off.



APF = 1 is the only value that seems to work at all.

Can anyone else confirm that APF works when set to 1?





Regards, Al / NN4ZZ  
al (at) nn4zz (dot) com
Photo of Sergey, R5AU

Sergey, R5AU

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Al, in case more precisely listening i am agree with :
APF = 2 tone
APF = 3 tone
APF = 4 dead, no audio
APF = 5 tone of the High Freq + air with tone level go smoothly to zero - dead after couple of sec.
APF = 6 dead no audio
however from 7 to 99 i am hearing real increasing of the Q of the APF filter, my preset as it was on 1.3.8 is 20 with both sliders of the EQ 600Hz+1kHz - +9DB and other with -9DB


P.S. with position 5 very vary from time to time
(Edited)
Photo of Sergey, R5AU

Sergey, R5AU

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In couple of minutes will be accessible short movie on http://youtu.be/ckuK_IFdUzM
with APF issue 
Photo of Al / NN4ZZ

Al / NN4ZZ

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Sergey,
Okay after more testing with wider filters I am seeing some Q effect at the settings between 7 & 100.  It's not very pronounced -- the signal doesn't really pop.   There is an idea to boost the gain for APF so maybe that is part of the reason.

https://community.flexradio.com/flexradio/topics/ssdr_v1_2_apf_could_use_more_gain_it_seems_diminish...

Also agree with your assessment of APF = 1.   With a narrow filter (100HZ or 50HZ) it seems like there is some Q effect but it may just be because the filter is narrow and the signal is boosted overall. 

What filter width are you typically using?   Do you still see an improvement when with narrow filters?

Overall, APF still need work IMHO.

Regards, Al / NN4ZZ  
al (at) nn4zz (dot) com
Photo of Sergey, R5AU

Sergey, R5AU

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Usually 400Hz or 250Hz, on movie 400Hz

You know definitely in ver 1.2 effect was WOW, but in other way around Steve is also right, necessary to define what really better(type of APF), i remember he replyed in some message after you post, sorry but not remember when it was
(Edited)
Photo of Al / NN4ZZ

Al / NN4ZZ

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Movie shows the tone problem well.  

When you have APF set to somewhere around 30, it would be good to see when you enable / disable APF button if there is a noticeable difference. 

Also whether the effect is the same when using a 100 HZ filter.

Regards, Al / NN4ZZ  
al (at) nn4zz (dot) com
Photo of Sergey, R5AU

Sergey, R5AU

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It is true Al, between 20 and 30 are usefull settings of APF