[Discuss-gnuradio] CPFSK grc block question ... problem with data types

[Michael Civ]

Hello all,

I am having the following trouble with data types:

I have the following flowgraph working to record FM broadcasts:
{USRP2 source -> LPF -> FM Demod -> File Sink}

Next, I am making another program to transmit the stored FM broadcast audio to my handheld radio which expects FSK modulation. So I would like to do the following:
{File source -> CPFSK mod -> LPF -> USRP sink}

The problem is that the grc CPFSK block expects bytes. This means that the recorded file has to have bytes, but the FM demod only outputs complex or float data types. Is there a gnu radio function (or grc block) that converts floats to bytes? Or is there a way to store the audio data as bytes in my first program?

Thanks in advance for your help,
Mike