Steve
2016-03-29 11:57:25 UTC
Playing around with SOX I was wondering how much I could filter the ME FM
waveform, and I was surprised that using the sinc 1k-3k option still
decoded nicely.
./freedv_tx 2400B ../../raw/ve9qrp_10s.raw - | sox -r 48000 -t raw -b 16 -c
1 -e signed-integer - -r 48000 -t raw -b 16 -c 1 -e signed-integer - sinc
1k-3k | ./freedv_rx 2400B - - | play -t raw -r 8000 -e signed-integer -b 16
-
The waveform actually sounds nicer (not so raspy as with the non-filtered).
I don't know how this would fair at long range though. Maybe doesn't need
to be so narrow.
â
waveform, and I was surprised that using the sinc 1k-3k option still
decoded nicely.
./freedv_tx 2400B ../../raw/ve9qrp_10s.raw - | sox -r 48000 -t raw -b 16 -c
1 -e signed-integer - -r 48000 -t raw -b 16 -c 1 -e signed-integer - sinc
1k-3k | ./freedv_rx 2400B - - | play -t raw -r 8000 -e signed-integer -b 16
-
The waveform actually sounds nicer (not so raspy as with the non-filtered).
I don't know how this would fair at long range though. Maybe doesn't need
to be so narrow.
â