[Discuss-gnuradio] filter ssb

[cswiger]

Mike's ssb demodulation works darned effeciently - this must be
the simplest ssb receiver:

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#!/bin/env python

from gnuradio import gr, audio, usrp
import ssba

def build_graph():

        target_freq = 3938e3

        rf_rate = 256000
        af_rate = 32000

        fg = gr.flow_graph()

        src = usrp.source_c(0,250)
        src.set_pga(0,10)
        src.set_rx_freq(0,-target_freq)
        freq_error = -target_freq - src.rx_freq(0)

        ssb1 = ssba.ssb_demod(fg,rf_rate,af_rate)
        ssb1.tune(freq_error)

        volume = gr.multiply_const_ff(.001)

        dst = audio.sink(af_rate)

        fg.connect(src,ssb1,volume,dst)

        return fg


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

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I'm using it to listen to hams at the moment, less than 10% cpu.

I think you have to reverse the taps to change sideband, i.e.,
change the sign of the exponentials in hfir.sci.

--Chuck