[Discuss-gnuradio] Demodulating digital signal (FSK?) from audio

[Stefan Oltmanns]

Hello,

I would like to write an application that checks the battery status of
wireless microphones. The battery status is transmitted as a very low
frequency (below 10 Hz) signal that is mixed in the normal audio. I was
able to filter the signal out of the demodulated audio and display it
(see image). AFAIK this modulation is called FSK.
The signal that is shown there should decode to data-blocks containing
"11100000000" or something like that, are there any blocks in GnuRadio
that can do that?
Because the signal is derived from audio it is not complex but normal
float, all GnuRadio demodulators seem to work only on complex data.
Can somebody please help me?

Best regards,
Stefan

demod_battery.png
Description: PNG image