kopia lustrzana https://github.com/ha7ilm/rpitx-app-note
1.1 KiB
1.1 KiB
Application note on using rpitx
Using with csdr to modulate streaming input
You will need the dev branch of csdr for doing this.
Setup instructions:
git clone https://github.com/simonyiszk/csdr.git
cd csdr
git fetch
git checkout dev
make && sudo make install
Note that it should be already done, if you installed qtcsdr.
Modulate from raw audio file
These examples will use the raw audio file testsound48000.raw
, which is present in this repo. You can get this file by:
git clone https://github.com/ha7ilm/rpitx-app-note
cd rpitx-app-note; ls #There is your file.
A raw audio file differs from a .wav file because it doesn't have any headers to store its parameters, just the samples after each other.
Generate AM modulation:
cat testsound48000.raw | csdr convert_i16_f | csdr gain_ff 1.0 | csdr dsb_fc | csdr add_dcoffset_cc | sudo rpitx -i- -m IQFLOAT -f 28400
- The part
csdr gain_ff 1.0
can be changed to increase/decrease modulation. - The
-f 28400
at the end gives the transmit frequency in kHz.