GNUradio using a signal as a variable.

[vini_i]

I'm trying to use GNUradio with an RTL-SDR to read the data transmitted by my vehicles keyfob.

I can receive the signal with SDR#. So that I don't have to sit there and push the keyfob button over and over I wanted to put together a simple chain that could simulate the keyfob signal. My best idea of what to do is to feed two separate frequency signals into a selector and the to switch between them with something to make a pseudo frequency coded signal. My best effort was to feed a signal source set to a zero to one square wave into a probe signal and then use the probe signal as a variable. This failed terribly. The selector does not recognize the probe signal as a variable. I'm not sure what else I can do.

My understanding of GNUradio if very limited. Is there anything else I can do?

 

[ansul1001]

Do you know what freq it is operating on or is that what you are trying to find out if you know the freq I can maybe help you

 

[vini_i]

Do you know what freq it is operating on or is that what you are trying to find out if you know the freq I can maybe help you

The scheme looks like frequency shift keying. With the frequencies being about 313.875MHz and 313.8125MHz.

 

[ansul1001]

you can try to use the fm receiver that is in gnu radio but then you will have to modify the bandwidth FM is 250000 and the freq you are interested in is 10000