Is there any kind of solution that does NOT involve even a microcontroller on the receiving end? I want to make a VERY simple, low-cost project.
Any range (only need like 15ft)
Any voltage
Any power consumption
(almost) any cost
1 GPIO pin (more OK)
I haven’t found anything so far and would love to hear what the community might have to say. Thanks.
a phototransistor stimulated by an IR LED seems the simplest, but I should add that there is no direct line of sight. The wireless signal must go through walls
Look at garage door opening and car entry TX/RX’s (Key Fobs).
I think SparkFun has one.
Here is a simple but complete kit:
this pair seems most appropriate (and also WAY cheaper than XBee!):
Cue the questions about why it doesn’t work in 3…2…1…
What are the on/off periods? How long does it stay on or off. These last mentioned receiver/transmitter pairs are not intended for slow steady signals. Also, it it does not detect the carrierwave of the transmitter, it will increase it’s amplification of the received signal. This might cause detection of spurious false signal changes.
Even lightswitch remote controls have a microcontroller to encode the ID of the switch or lamp, and to encode it a fashion that is a not-static signal level. (look-up manchester encoding.)
Garage door opener