I’ve set up the RF Link 434MHz, and want to simply turn on and off an LED using the data pin. However, when I send a signal out to the receiver, the LED turns on and immediately off. Is it not possible to send a continuous ‘high’ signal through the transmitter?
Hi, tell us which receiver you purchased and we’ll try to sort it out.
-Mike
SparkFun Tech Support
This transmitter / receiver pair has a maximum pulse width of around 30 milliseconds. If you hold a steady voltage on the transmitter’s data pin for any longer than 30ms, then the automatic gain control on the receiver will drift away and it loses the signal.
One thing you could try would be to use some kind of pulse-width modulation to make the LED mostly-off or mostly-on. E.g. on the transmitter, you could switch between a 0 and a 1, and vary the time for each, like this:
LED Off: Send “0” for 29 milliseconds, send “1” for 1 millisecond
LED On: Send “1” for 29 milliseconds, send “0” for 1 millisecond
This will make sure you have a 0-1 or a 1-0 transition every 30 milliseconds, which should prevent you from losing the signal.
The receiver unit may not be able to put out enough power to drive an LED directly. You might need to use a transistor or some kind of gated buffer.
Yeah I figured. Thanks, makes sense.
And don’t worry, a transistor was used 
Can you post a schematic on how you are doing it? I’m an electronic newbie and don’t know how to do it.