Are any of these transceivers better than the others, in terms of range and powerline signal strength ?
My existing setup consists of 12 devices on 5 different house codes. 9 are hardwired switches on 4 different house codes. 3 are plug-in, each on a different house code. Using the CM11A, PLC signals only reliably reach about half of them. The others almost never work. I have many more switches and plug-in modules in a drawer, uninstalled, that I'm not using because of the noise problems.
I also have a CM17A, and two RF-X10 transceivers, models RTM75 and RR501. I have found that the RF reach of the CM17A in my office is pretty good. It reaches through several room/walls. By placing the transceivers on different outlets, and changing their house code, I'm able to control at least 11 devices (haven't checked on the 12th yet, it's not very important) reliably. At least, I was able to at the time of the day that I tested. I'm not sure it would work all the time. But this is encouraging as there was zero mishap so far in this test.
I will need at least one more transceiver, though. Consolidating all devices onto one or two house codes would not be enough - I need to use at least 3 outlets to reach every existing device, and thus, at least one more transceiver.
Thus, my question - which additional transceiver(s) models would be preferred ? I probably wouldn't be plugging anything into any of them, so any differences related to 2-pin/3-pin outlets, or wattage, is irrelevant. I would prefer a module without a relay/outlet at all, actually.
I am also wondering why X10 never made a transceiver that works on all house codes. As far as I can tell, the X10 RF protocol sends both the house code and unit code over the air. But the transceivers retransmit only signals for the house code they have specifically been setup for. It seems a bit silly. I suppose it makes sense in apartments or houses very close to each other. But there is no issue of interference with neighbors in my case, so a transceiver without any house code / unit code / outlet would work best.