I bought one of the original TED 1001 versions when they were being dumped last year for just $15. Yesterday I finally got around to installing it, using our XPF isolated "electronic circuit" for its communication. While the indicator worked fine when plugged into the same isolated outlet as the sender, it would not register readings when moved into my office and plugged into the same circuit. Like with X10, the UPS and computer loads on that circuit must be too much for the TED signal to get through.
While our X10 operation seemed to be behaving properly after the installation, last night the landscape lights missed their scheduled "ON" transmission even though the Leviton 16400 indicated it had been sent. Later in the evening I noticed the hall lights had not dimmed down to their nighttime setting. And today while testing a new production XTBM-Pro, it was indicating a continuous stream of Bad Start Codes.
Even though that circuit is isolated with the XPF filter, there must be enough TED signal leaking through to interfere with some X10 devices on the same phase. While the XTB-ANR squelches most of the TED signal, those signal bursts that have the same profile as actual X10 transmissions still come through. What worked was to isolate both the transmitter and receiver with a second X10 filter (XPPF) plugged into the isolated electronics circuit.
Thinking about it, it doesn't surprise me that a single XPF didn't attenuate the TED signal sufficiently. TED uses a frequency where X10 modules are most sensitive. So even though the XPF knocks down the signal level by at least a factor of 10, enough is left to cause problems for some X10 modules.