This has been a dormant thread for quite a while, do to other matters taking priority, but thought I might now update this "long strange trip" with my X10 experience...
I kept the breaker switch for the XPCR off for the past 8 months and have been utilizing the Signalinc only. As previously noted, I have been getting fairly good signals only on Phase A, and nothing on Phase B. This weekend, I had a little time to play with the XPCR again so I unplugged the Signalinc from the dryer outlet, turned on the breaker that the XPCR is on and... lo' and behold I am now getting signal response on 80% of Phase B!
I've been wracking my brain trying to think of anything that has changed in the household. There are no new electronics added or subtracted. The only thing remotely I can think of is that I had to replace a PS on my computer. That computer is on a line filter, by the way.
The other possibility...and this is only for X-Files fans. My house is about 1,000' down-range from a fairly substantial "Naval Communications Training Station." I am 50 miles southwest of DC, and the largest body of water nearby will accept nothing larger than a 12' rowboat. So... why, you ask, does the Navy have a "training station" out in the countryside? Seems the mountain they are on has a nice, clear line of sight into DC. Draw your own conclusions from there!
Now, during the past year, on a couple of occasions, cable crews have come through our neighborhood running new cables that go straight up the hill. They aren't going in to improve our internet access, that's for sure!
Could it be possible that some radio transmissions are being moved to cable transmissions and thus eliminating some potential interference?
Conspiracy theory? Perhaps. But maybe not?
Anyway, since my last post, my XPCR has unexpectedly begun to perform very nicely! I haven't fully tested all the Phase B outlets yet, so I'll have to do a little more work before making a final debriefing on the matter.