i am re-posting this project.
I have a portable wireless receiver (reciever only) which has buzzer, speaker, leds, switchs, and 433MHZ receiver.
i need this device to be able to "learn" a signal, and alert if detected.
the signal is based upon EV1527/RT1587E protocol (20 bit address + 4 bit data).
i added files for more information.
One thing we could not find - is how to measure VDD voltage, as it need to alert on low battery.