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@cdgraff
Forked from cannikin/rtl_fm options
Created February 26, 2018 01:01
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rtl_fm, a simple narrow band FM demodulator for RTL2832 based DVB-T receivers
Use: rtl_fm -f freq [-options] [filename]
-f frequency_to_tune_to [Hz]
use multiple -f for scanning (requires squelch)
ranges supported, -f 118M:137M:25k
[-M modulation (default: fm)]
fm, wbfm, raw, am, usb, lsb
wbfm == -M fm -s 170k -o 4 -A fast -r 32k -l 0 -E deemp
raw mode outputs 2x16 bit IQ pairs
[-s sample_rate (default: 24k)]
[-d device_index (default: 0)]
[-g tuner_gain (default: automatic)]
[-l squelch_level (default: 0/off)]
[-p ppm_error (default: 0)]
[-E enable_option (default: none)]
use multiple -E to enable multiple options
edge: enable lower edge tuning
dc: enable dc blocking filter
deemp: enable de-emphasis filter
direct: enable direct sampling
offset: enable offset tuning
filename ('-' means stdout)
omitting the filename also uses stdout
Experimental options:
[-r resample_rate (default: none / same as -s)]
[-t squelch_delay (default: 10)]
+values will mute/scan, -values will exit
[-F fir_size (default: off)]
enables low-leakage downsample filter
size can be 0 or 9. 0 has bad roll off
[-A std/fast/lut choose atan math (default: std)]
Produces signed 16 bit ints, use Sox or aplay to hear them.
rtl_fm ... | play -t raw -r 24k -es -b 16 -c 1 -V1 -
| aplay -r 24k -f S16_LE -t raw -c 1
-M wbfm | play -r 32k ...
-s 22050 | multimon -t raw /dev/stdin
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