Re: X-10 Antenna Interference...

[nobody@xxxxxxxxxxxx (Dave Houston)]

No, antennas do not absorb the signal and thereby weaken it for others. If
that were the case, the more people who put up radio and TV antennas, the
worse everyone's reception would be and the radio and TV stations would have
to continually increase the strength of their signals to compensate until
they and their audience were cooked by the radiation. For that matter, any
metal will act as an antenna whether coupled to a receiver or not.

There can be subtle interactions between antennas but they are too complex
to analyze easily. The effects can be both positive and negative.

However, the RF receivers that X-10 uses in their transceivers (except for
the CM15A) are of a type called "superregenerative receivers" and they can
interfere with each other if they are too close because they also radiate
energy. This is likely to have a much bigger effect than any antenna
interactions.

The simple answer is that if your setup works for your purposes, go for it.

"Michael G." <514mike@xxxxxxxxx> wrote:

>Hi again!
>
>I have a question that isn't really so much about Home Automation as it
>is about radio waves and antennae:
>
>Right now, I have two transceivers plugged into the same socket.  I
>actually extended each antennae so that they look like bunny ears.
>
>>From a physics point of view, do multiple antennae interfere with one
>another?  Does an antenna "absorb" the signal, thus weakening it for
>the other device?
>
>I do not know much about this stuff, but intuitively, I would say they
>would not interfere with each other.
>
>If I had ten FM radios on a table, would the signal get progressively
>worse for each radio as each antenna was extended??
>
>Or taken a step further... if everyone in a city tuned into the same
>radio station, would that affect the station's signal?
>
>I have so far experienced no problems (I think).
>
>I have two transceivers piggybacked in one outlet, and in another
>outlet, I have a third transceiver.  My remotes and sensors seem to
>work 98% of the time.
>
>I would love to take all three transceivers, and plug them in a power
>bar, side-by-side.  I can then add a fourth as well, and hide it.
>
>Do you think that is a good thing, or a bad thing?
>
>I'm sorry if this is a basic radio/physics question, but I don't think
>the answer is so obvious...!
>
>Thanks!
>
>Mike