JP1 Remotes

So the transceiver is not needed if you have a IR543 in the mix?
Right, the transceiver is for handling RF signals, the IR543 converts IR signals into X10 signals.

Everything is on the same house code. I have 3 modules 1,2 and 3. 1 is the transceiver. 2 and 3 are lamp modules. They all work fine ...

the RF Transceiver is always unit code #1. If you have appliance and light modules, code them for the same house code as the IR543, give them different unit codes other than #1. and unplug the RF transceiver try to control the modules. So the transceiver is not needed if you have a IR543 in the mix ...

The Robman wrote:What does the term "primary" mean in this case?

The X10 module that has the antenna and is device 1.

A, C and O are "house codes", you only need to change that if you have multiple IR543 units scattered around the house, which it doesn't sound like you do. If you only have one IR543 unit, just use the main A house code.

You control the individual modules by giving them different "unit codes". My ...

I just got an IR543 and I can't get it to control anything except the first module (with the antenna). I have my modules on 1-8 and I tried A, C and O and only the primary module works.

I can turn the first device on or off from the IR543 or my Pronto remote. But if I try my modules on 2,3 or 4 ...