1
\$\begingroup\$

As part of a larger project, I would like to be able to replay signals of this remote. It's a remote for a temperature controller, operating at 433MHz and it looks like it's using ASK modulation.

I've bought an RTL-SDR dongle and recorded the remote signal using SDRSharp (see Audacity screenshots). Each button press (increase/decrease temperature) produces 6 packets that are exactly the same.

From reading a few blogs it seems that the common assumption is that each fat/thin pulse corresponds to 0/1. Is that a reasonable assumption? Also, do I need to replay all 6 packets and does the interval between the packets matter? Any sense in how accurate my timing (ie baud rate) needs to be?

Singe button press

Single packet

\$\endgroup\$
  • 1
    \$\begingroup\$ no, there aren't any "libraries" that allow you to record the waveform. you need a spectrum analyzer with video out. set it to 0 span, and output to an oscope and analyze the waveform manually. then pray to god, that the the communication is not encrypted \$\endgroup\$ – hassan789 Apr 6 '15 at 1:23
3
\$\begingroup\$

You can use RTL-SDR dongle and either put together a decoding package using gnuradio or see if anyone did this already for your remote. Protocols for many remotes, utility meters, weather stations, etc. have been reversed already.

To replay the data you'll need a transmitter. There are ham radios for your band but chances of finding ready-made software for your protocol are low. Again, gnuradio can be used for that.

| improve this answer | |
\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.