I am trying to send commands to my ceiling fans using an Arduino Nano and an RF transmitter (UCEC XY-MK-5V). It took me a long time to get to this stage but I believe I currently have the right commands and can duplicated them. However, the fan does not respond to the commands. The fan is listed as a 434MHz RF device and using SDRSharp I believe the frequency is 433.925MHz. I then used Universal Radio Hacker to record the signals from the remote. I then used the Arduino to transmit the signal. Attached is an image that shows parts of the signal. At the bottom is what I recorded from the remote and on top is what I emit. They copy is pretty close in timing to the original. Note that this is just the beginning and there is about 4x more after that but again the timing is quite similar. The biggest difference is that the original only shows 4 sinus waves per bit while the copy has many more (which is why it shows up as black). I have a feeling that I can’t really trust those signals though because the device runs at 434MHz and I am sampling at 1Msps. So I really only record the on-off states and what is in between is random. Still, maybe this is the reason why I can’t control the fan. If anybody can shed some light on this I would really appreciate it.
Looks to me that your carrier frequency is way too high compared to the original waveform.
I've never used the 433MHz radio modules, but I imagine all you need to do is send the message envelope to the radio and the radio sends the envelope modulated at the correct frequency, resulting in the correct waveform.
Can you post your Arduino code?