#!/usr/bin/env python

from gnuradio import gr
from gnuradio import audio

def build_graph ():
    sampling_freq = 32000
    ampl = 0.1

    fg = gr.flow_graph ()
    src0 = gr.sig_source_f (sampling_freq, gr.GR_SIN_WAVE, 350, ampl)
    src1 = gr.sig_source_f (sampling_freq, gr.GR_SIN_WAVE, 440, ampl)
    dst = audio.sink (sampling_freq)
    fg.connect (src0, (dst, 0))
    fg.connect (src1, (dst, 1))

    return fg

if __name__ == '__main__':
    fg = build_graph ()
    fg.start ()
    raw_input ('Press Enter to quit: ')
    fg.stop ()