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FRS should add feature to Flex6700 to Noise Nulling ability like the ANAN Radio's see HPSDR Phase N

edited January 7 in New Ideas
FRS should add feature to Flex6700 to Noise Nulling ability  like the ANAN Radio's see HPSDR Phase Noise Cancellation (+NB): ANAN-100D

since the Flex6700 has two separate A/D's to Phase and Amplitude adjust Interference out
of Radio 

see youtube video


73 Mike
2 votes

Open for Comments · Last Updated


  • Jim GilliamJim Gilliam Member
    edited January 2017

    MFJ has a similar unit. It requires two antennas. The big "IF" of the success of this technique is that one antenna should be subjected to a higher noise than the second antenna. This gives the unit enough information to discern between wanted and unwanted signals. If Flex were to implement this it might cause more problems than it solves in that meeting the conditions of subjecting one antenna to the noise source more  than another could be problematic and cause more complaints than praises.

    Jim, K6QE

  • edited January 2017
      Do not see complaints on ANAN forum but many praises  for this feature

    I do have a NCC-1 and can do it external but cost me $800 for the RT1A and NCC-1
    combo, be easier if built into software since you have two A/D's in Flex6700
    73 Mike
  • Jim GilliamJim Gilliam Member
    edited January 2017

    Hams have a tendency to over sell this technique. I had reasonable success using a vertical antenna as the noise antenna and a horizontal for the communications antenna. At times I could get a null as high as 10 dB, however, at other times, I could hardly get a null depending on how the noise propagated with time of day, weather, etc.

    Jim, K6QE

  • edited January 2017
      For local noise from a neighbor, usually is not an issue as long as noise Sense signal has a slightly higher signal than noise into main antenna this technique works
    quite well.

    The real issue/challenge  is multiple noises, that is hard to null out all at same time

  • Allan BatievskyAllan Batievsky Member
    edited November 2018
    I had sever noise problems coming from a close, coherent source. Not hash, wideband noise. It has to be close, and it has to have a determinate pattern for de-phasing to work. Tried several noise antennas (different polarization, different lengths...) and when you find the sweet spot, you can literally null out the noise and bring the band back. The offending noise here is gone from 15 and 17m, it was a neighbour with a small "plantation" at home with cheap, noisy chinese sodium light ballasts. A friendly visit with a portable spectrum analyzer fixed the problem, once he learned how he was broadcasting his wrong doings with a 599. It would be an incredible feature to implement on a Flex, specially for urban hams in noise infested locations (that's almost everywhere now). 

    73 DE EA3HSO

    Here's a link to a badly shot video of an ANC-4 demo at the shack.
    Signals keep almost the same, noise dissapears.


  • KE9NSKE9NS Darrin Kohn Member ✭✭
    edited January 7
    The ESC feature of PowerSDR using a Flex-5000 (with 2nd RX) can do noise nulling as well. I made a youtube video a while back showing it in operation. It worked great when I had a beam ant. on the 1st receiver and a vertical ant. on the 2nd receiver.

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