Thanks for your additional comment on this. I really appreciate it. However, so far the one from sghioto is working flawlessly with my RF433 module(from 5 volt to 12 volt). Sorry, I have no background on this electronics thing.Hi guy. This is your circuit simulation result.
Since the pulse time is very short, and the amplitude is not very high. I think you should an additional circuit behind to rectify the wave, something like a GATE logic nor complicated like a voltage comparator with a low threshold settings.
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