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Audio hiss with narrow filters

K2CMK2CM Member ✭✭
edited September 2019 in SmartSDR for Windows
When I narrow the filters down to 100 or 50 hz, I get audio hiss. The copy ability would be vastly improved if this hiss could be reduced. I worked the EU contest over the weekend and had difficulty with weak stations. I could clearly see the CW on the pan adapter; but, could not copy the stations due to hiss.

Completed · Last Updated


  • Ed.GEd.G FlexRadio Employee ✭✭
    edited February 2017
    I believe this is due to the previously reported audio aliasing issue. This caused a discernible hiss around 12-15 kHz. With a wide filter, the passband audio was probably strong enough to cover up most of the hiss. With a narrow filter the opposite was probably true. The aliasing issue is resolved in the next release so the hiss should be gone. If it's not, please let me know and I'll look more into it.
  • K2CMK2CM Member ✭✭
    edited September 2019
    Will check and report back after the next release is available.

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