Re: [Discuss-gnuradio] FSK transmitter tutorial

[Ron Economos]

I have a RTTY flow graph that you may find useful as a starting point. 
It's transmit only (I was just using it to test the RTTY decoder on the 
ICOM IC-7300 ham transceiver).

http://www.w6rz.net/rtty.grc

And a program to generate a baudot test file from a text file.

http://www.w6rz.net/baudot.c

Ron

On 03/20/2018 04:48 AM, Murray Thomson wrote:
> Hi,
>
> I would like to build an FSK modulator/demodulator. I'm using file 
> sink/sources for the moment. I need to be able to specify the two 
> frequencies, baud rate and sample rate (ideally at runtime).
> I started with the gr-tutorial for qpsk, hoping to replace the 
> modulation/demodulation with gfsk blocks, but I didn't get the result 
> I was hoping for. I don't fully understand the gfsk module or how to 
> change the frequencies after the modulation. I tried the fsk burst 
> modem example, but it's not what I want. I would rather not use PDUs 
> and I don't want to transmit in bursts.
>  I would really appreciate if someone could point me to a tutorial or 
> example on this. These are the resources I have read so far:
>
> https://github.com/gnuradio/gr-tutorial/blob/master/examples/tutorial7/mpsk_stage6.grc
> https://nccgroup.github.io/RFTM/fsk_transmitter.html
> https://www.reddit.com/r/GNURadio/comments/3u5zp2/gnu_radio_gfsk_modulation_rate_deviation/
> http://www.indigresso.com/wiki/doku.php?id=opentag:radios:testing_with_gnuradio
> https://oshearesearch.com/index.php/2015/05/31/building-a-burst-fsk-modem-in-gnu-radio-with-message-lambda-blocks-and-eventstream/
>
> Many thanks,
> Murray