Do modules attenuate X10 line signals like some electronics do?

[roger1818]

If I add a repeater I'm going to get double (or more) responses from the devices inside the house as they receive the signal from the RR501 (or CM15A) then again from the repeater/amplifier.

I don't want my dimmers to operate at warp speed, thank you very much.

Most if not all modern coupler/repeaters (my reccomendation is the ACT CR-234) won't cause this problem.  Standard X10 signals are sent twice anyway and the CR takes advantage of this.  Bright and dim commands are handled in a special way so that they will behave properly when "repeated."  Phil Kingery explains the two ways this is done in his article Which One Should I Use, Part V: Dim/Bright Commands and Coupler-Repeaters.

[dave w]

but signal amplifiers in general can actually make strong signals weaker. 

Poodle gas!! Please explain.

If the amplified signal is out of phase with the X10 signal (I am not talking about the phase of the 60Hz powerline signal, but the phase of the 121kHz X10 signal), the two signals can either partially or completely cancel each other out. 

I am confused. Unless you are talking about something that can only happen on the same branch as where the controller signal originates(?) this is common?

[roger1818]

If the amplified signal is out of phase with the X10 signal (I am not talking about the phase of the 60Hz powerline signal, but the phase of the 121kHz X10 signal), the two signals can either partially or completely cancel each other out. 

I am confused. Unless you are talking about something that can only happen on the same branch as where the controller signal originates(?) this is common?

You are right in that this typically this only happens when the amplifier is on the same circuit as the transmitter or in an outlet that is close to the breaker panel where a coupler/repeater is installed. 

From what I can tell, the XTB is immune from this problem as it seems as though it will only amplify signals from the device plugged into it and not any signal it sees.  I may be wrong about this though (as I said before, I don't know much about the XTB).

Unless you only have one transmitter and don't ever plan on using 2-way modules, I would reccomend using a Coupler/Repeater if you are having signal strength problems.

[JeffVolp]

From what I can tell, the XTB is immune from this problem as it seems as though it will only amplify signals from the device plugged into it and not any signal it sees.

That is correct.

With respect to repeaters, the Leviton 6201 did not increase my signal levels significantly, as measured with an ESM1.    Replacing the 6201 with the XTB gave me much stronger levels throughout the house (when the XTB was moved near the electrical  panel).  It also gave me micro-dim capability, which the 6201 was somehow masking.

[roger1818]

With respect to repeaters, the Leviton 6201 did not increase my signal levels significantly, as measured with an ESM1.    Replacing the 6201 with the XTB gave me much stronger levels throughout the house (when the XTB was moved near the electrical  panel).  It also gave me micro-dim capability, which the 6201 was somehow masking.

Sounds about right for the Leviton 6201 (it is actually designed an manufactured by X10).  I recommend ACT CRs.  They cost more, but they provide a larger output and I like the way it handles bright and dim commands better.