I have been asked several times about the relay that I have behind my TV that operates the projector screen and PC buttons. So here is an annotated photo to help explain it better. The 12V power for it is actually routed down from the loft so it works even when the spur in the lounge is off. This is so I can turn the PC on without having to turn the spur on.
This pre-assembled relay from Quasar Electronics has jumpers so that each relay can either latch or be momentary. For the screen and LED lights it must be set to latch, and for the PC buttons to momentary. You can click on this image for a larger version
Then inside the PC in the attic, the 4 core cable is spliced to the power and reset cables respectively.
And then the little RF remote works for me as follows from the comfort of my sofa…
…and this is the relay as it comes (pre-assembled model) from Quasar
wonders whether you could 'learn' this from an rf harmony remote.
Good question. The Gyration remote(s) I use only learns IR and not RF, otherwise I would try it. Although I can't see why a Harmony wouldn't work as it's all on the same 2.4Ghz spectrum.
Having said that, the receiver unit can pair with several different transmitters, so maybe it could learn a generic command from an RF remote. If I get a minute I'll try it with my Gyration remote…
I tried pairing the relay behind the TV last night to my Gyration remote and unfortunately it doesn't work. I remember trying to pair it with another brand 4 button transmitter a few months ago (as the wife had lost the original transmitter – £20 to replace!!) and that didn't work either, so I guess the relay is locked to a certain type of transmitter.
But as for whether the transmitter could be learnt by another RF remote I do not know.