I'm trying to control a HomeEasy remote with the Arduino. I followed the instructions on this page http://www.instructables.com/id/Arduino-Home-automation/step2/Basic-principle/
(Arduino pin --> optocoupler --> remote switch)
However instead of using 8 cables for the 4 on/off remote switches I used a 4051 demux so that I can save some pins on the arduino. I also did not use any LEDs.
If I go from an Arduino pin directly to the optocoupler and send a signal, the remote switches as it should.
If I measure resistance on the optocoupler on the side of the HomeEasy remote... and send something through the demux... I can see that the optocoupler is indeed switched...so the circuit is ok I guess... but the remote does not react at all... :(
Could this be a problem with too much resistance? What can I do to fix this? Sorry I'm a beginner on circuits.
The optocouplers I am using http://uk.farnell.com/vishay-semiconductor/ild1/optocoupler-transistor-o-p/dp/1469477
The demuxer I am using http://at.farnell.com/nxp/hef4051bp/single-8-chan-mux-4051/dp/385347?Ntt=385347
Thanks for your help
--- another update
Heureka! I found it. Turned out that when I had all outputs of the 4051 connected, I was sending always, even when LOW, LOW, LOW as input. But the remote didn't seem to like that and couldn't switch. When I unplugged the wire going from Y0 --> switch 1 OFF it worked! That means currently I cannot turn off switch 1... but at the moment I only have 3 things to control anyway and I could extend the circuit :)