Help with the Parallax 433 MHz RF Receiver

NaOH

I'm am very new to wireless circuits and would like help to make a simple on/off switch using the Parallax 433 MHz RF Receiver and transmitter. If any one could help me that would be great.

Mike Green

A lot depends on where you're located, whether there are other 433MHz signals floating around.

The 433MHz receiver and transmitter can be used directly for on/off signalling since the receiver puts out a logic 1 if there's a signal present and a logic 0 if there's no signal and you can use that to trigger a relay of some sort to switch whatever you want. There's no way to distinguish this signal from noise or an interfering signal on the same (or nearly the same) frequency.

Typically, you'd use a Stamp or some other microcontroller on each end and the microcontroller would actually transmit serial asynchronous data (like some characters) using the SERIN / SEROUT statements of the Stamp or their equivalent. The receiving Stamp would look for the specific data wanted and trigger the relay on a match.

Dgswaner

Start with the demo code and get them talking, IHO, the biggest mistake when first using these modules is setting the correct Baud rates, there is a chart on page 397 of the Stamp Manual that will tell you which value to use for the serout and serin commands for stamps. keep in mind that a BS2 can't reliable communicate via these adapters above 2400 baud but a BS2SX and others can. give it a shot, if your still having trouble you'll need to supply more info, which micro processor your using, code etc.

good luck!

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"A complex design is the sign of an inferior designer." - Jamie Hyneman, Myth Buster

DGSwaner