rtl_fm bandpass filter for CTCSS sub-tone

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koval
Posts: 6
Joined: Sun Feb 22, 2015 4:07 pm

rtl_fm bandpass filter for CTCSS sub-tone

Post by koval » Sun Feb 22, 2015 4:14 pm

Hey!

I am using rtl_fm on my computer.

This command work great on my windows xp system

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rtl_fm -M fm -f 433.075M -s 12k -g 40 -l 20 | play -r 12k -t raw -e s -b 16 -c 1 -V1 -
For now I need to use lowpass and highpass filter for audio signal. I need to filter CTCSS sub-tone.

When I am trying to run

Code: Select all

rtl_fm -M fm -f 433.075M -s 12k -g 40 -l 20 | play highpass 300 lowpass 3000
 -r 12k -t raw -e s -b 16 -c 1 -V1 -

it show me an error
"play FAIL sox: Not enough input filenames specified"
Does anybody know how can I use bandpass filter correctly?

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