I had been doing some noise testing, and out of curiosity I decided to compare the various X10 filters I have. The testing was done on an isolated lab circuit with about a 50 foot electrical run to the panel. Testing was done using a X10 Maxi Controller as the signal source, and the infamous Lumoform LED light as the noise source. Readings were made with the XTBM-Pro, which measures noise just before, during, and just after the X10 transmission window.
There were two surprises. One was how poorly the 20A XPF filter performs. It is essentially a severe signal sucker itself, and does not do well blocking noise from the LED light. And I was surprised that the 15 amp XTB-F15 performed significantly better than the 15 amp ACT F120, both from a signal loading and a noise rejection standpoint.
I knew the X10 XPPF was a good filter from prior testing. This test confirms the XTB-F10 performed as well for noise rejection, and the XPPF actually loaded down the Maxi Controller more than the XTB-F10. The XTB-F15 doesn't do quite as well because it uses lower value inductors to handle the higher current.
Rating X10 Level Pre X10 Window Post X10
No Filter ----- 8.12V .03V .99V .98V
XPPF 5A 7.32V .01V .01V .01V
XPF 20A 3.32V .01V .15V .14V
AF120 15A 6.20V .01V .04V .04V
XTB-F10 10A 7.88V .01V .01V .01V
XTB-F15 15A 6.88V .01V .02V .02V
Jeff