Hello Kevin, Thanks, your link had useful information about the principles to consider with a vector source.
Considering the following generic flowgraph : Vector Source > Repeat > Multiply (with a sine wave) > Resampling / Filtering > Output (?) I have seen that most of the variables are related to the Morse code transmission with the words per minute. However, I was wondering about how to tune the interpolation rate of the Repeat block after the Vector source for a known bit sequence, but out of the Morse standard. I would also expect some kind of periodic signal, if not an audio signal, at the input of the FM transmitter (I guess). What would you expect as a clean signal at the input of the FM transmitter (output here), if not an audio signal ? I am also wondering about how to set the cut off frequency and transition width of the low pass filter in these flowgraphs. Is it by hand, or is there a relationship with the flowgraph variables ? Thanks for your feedback! Anthony Le jeu. 2 juil. 2020 à 18:39, Kevin McQuiggin <[email protected]> a écrit : > > https://hackaday.com/2020/04/14/pluto-might-not-be-a-planet-but-it-is-an-sdr-transceiver/ > > Whoops! Here is the link! > > On Jul 2, 2020, at 9:36 AM, Anthony B. <[email protected]> wrote: > > Hello, > > Thanks for the answers! > > Is it this project ? > https://github.com/duggabe/gr-morse-code-gen > > I'm gonna check it out, but it looks like the idea is in there, thanks! > > Anthony > > > > > Le jeu. 2 juil. 2020 à 18:21, Alex Humberstone < > [email protected]> a écrit : > >> Hey Kevin, I don't see the link that you mentioned, did you forget to >> include it? >> >> >> On Thu, 2 Jul 2020 at 11:18, Kevin McQuiggin <[email protected]> wrote: >> >>> Hi Anthony: >>> >>> Check out this link. The author is using a Pluto but he developed a >>> flowgraph to transmit a vector that represents Morse code. Pretty >>> well-explained. The ideas you need are likely in there. >>> >>> Kevin >>> >>> >>> > On Jul 2, 2020, at 8:40 AM, Anthony B. <[email protected]> wrote: >>> > >>> > Hello all, >>> > >>> > I am trying to build a very simple FM Transmitter using a flowgraph as >>> a reference. The principle is the following : >>> > Signal source of 48 kHz Sample Rate > Rational Resampler up to 360 >>> kHz Sample Rate > Add Constant 1 > VCO at 360 kHz with a carrier frequency >>> at 120 kHz. >>> > >>> > What I am trying to do right now is to replace the signal source with >>> a vector of bits coming from another application to then modulate it with >>> FM. >>> > I've seen many examples of this kind of transmitter with audio input, >>> but I don't understand how to pass it a vector of bits and to get the >>> expected result. >>> > Is there something I should consider before going to the VCO ? Is the >>> principle only working with periodic signals as input ? >>> > >>> > Thanks for your help! >>> > >>> > Anthony >>> >>> >> >> -- >> Sincerely, >> Alex-M-Humberstone >> PhD Student >> Klipsch School of Electrical Engineering >> New Mexico State University >> Las Cruces, New Mexico >> >> >
