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dawsonjon / PicoRX

Build a SDR SW/MW/LW Receiver with a Raspberry Pi Pico
MIT License
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Added audio de-emphasis #82

Closed mryndzionek closed 2 months ago

penfold42 commented 2 months ago

cool!

could the de-emphasis settings be stored in 2 bits of rx_features (next to flag_enable_auto_notch)

mryndzionek commented 2 months ago

cool!

could the de-emphasis settings be stored in 2 bits of rx_features (next to flag_enable_auto_notch)

Done.

penfold42 commented 2 months ago

super quick! I should probably move my oled_contrast setting into idx_hw_setup too

dawsonjon commented 2 months ago

Thanks, great work as usual! The 50us and 75us settings have a break-in frequency of 3.1 and 2.1 kHz which is quite close to the audio cutoff frequency. I wonder if different settings would be better for narrow band modes? I had a quick search to see if there was any info on this, but couldn't find anything definitive, do you know of any good references?

mryndzionek commented 2 months ago

Thanks, great work as usual! The 50us and 75us settings have a break-in frequency of 3.1 and 2.1 kHz which is quite close to the audio cutoff frequency. I wonder if different settings would be better for narrow band modes? I had a quick search to see if there was any info on this, but couldn't find anything definitive, do you know of any good references?

Hmm, I only see a KiwiSDR thread here. "Designing" the filter is not complicated, so we might even add tau as input parameter.