We have been using X10 for automation control since it was introduced in the 70’s. I still have the Radio Electronics issue that first described how it works. We replaced a couple of failure-prone mechanical timers with lamp modules and that old blue electro-luminescent timer with the slide switches. No more worn out mechanical timers!
As with most people, our system gradually grew. We added a few wall switches to control exterior lights, X10 floodlight, and motion detectors. The palm-pad RF link gave even greater convenience. Automation was becoming part of our lives.
Like most good stories, there has to be a bad guy. In our case it was the Sony XBR TV we bought over a decade ago. A lamp module in the family room became cranky. And the exterior post light sometimes did not switch. Replacing the wall switch appeared to help marginally. Eventually, adding an old Leviton 6201 repeater did solve the problem with the post light. And a lot of troubleshooting showed that unplugging the Sony TV made the lamp module work better. The solution was to put a filter on the TV. Around that time I beta tested the CM11A and CM14A, and our house grew smarter.
During those years I learned a lot about how X10 really worked. I learned about phase coupling, noise sources and “signal suckers”. Back then everybody said X10 problems were due to interference from noise sources. Well, that isn’t really true. Most problems are due to low signal levels caused by electronic devices that attenuate the signals. I bought an ESM1 signal level meter before it became the “Elk” ESM1. Any problem was quickly isolated, and resolved with an appropriate filter. That was when I learned how to deal with the early compact fluorescent lights.
Fast-forward a few years… We built our “retirement” home. Having had good luck with X10, I planned it to be fully X10 controlled – lights, irrigation, ventilation, etc. Knowing about phase coupling issues, I connected all “X10” circuits to the same phase. No coupler was needed. A single circuit was run throughout the house to power “unfriendly” devices, such as computers, TVs, and some other electronic equipment. That is run through a 20A X10 XPF filter, and can be powered by a huge UPS. To prevent possible future problems, I installed Leviton 6287 "noise blocks" on all circuits feeding CFL ceiling lights.
OK, so I did everything right here. Except for the XPF, 6287s, (and a whole-house blocking coupler), no other X10 filters were used. We upgraded to Leviton wall switches throughout for full rocker action, and added several 16400 indicating controllers. Since X10 had dropped development of the CM14A, I also upgraded to the Ocelot. Things were good.
After a couple of years, we began to notice one light sometimes did not turn off. Electronic devices continue to proliferate. Digging out the ESM1 showed X10 levels were low on one central circuit even with all other devices unplugged. The sheer number of X10 loads (especially transmitters) was now loading down the signal levels.
After some thought, I decided I had to boost the output of my TW523 powerline interface. The XTB was originally designed for just that application. In fact, an early version needed a wire connection between the two units. That evolved into the units that are available to all today. More info on those units is available here:
http://jvde.us/xtb_index.htm
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Topic: XTB Background (Read 41990 times)