Paul: Donald is right. One other thing is
if the signal is strong a signal amplifier
can actually make the signal weaker (the
original and amplified signals can cancel
each other out). Besides, it doesn’t
matter how strong your signal is if the
module interprets the noise as a signal.
Modules with AGC are better at picking out
a strong signal in a noisy environment or a
weak signal in a quiet environment.
Having said that, if the devices in
question are absorbing signal and not
generating noise (it is difficult to
differentiate these two without a signal
monitor), a signal amplifier might help.
One alternative is to put a 20A filters on
circuits that have several noisy devices.
This will prevent X10 devices from working
on those circuits though so be careful
where you install them.
Another alternative is to use a shunt
filter (such as the ACT AF310). A shunt
filter will filter out noise that is above
or below 120kHz without affecting your X10
signal. Obviously, if the noise is at or
near 120kHz, a shunt filter won’t help, but
it can help with some types of noise.