X10 Feng Shui

X-10 makes several wireless sensors - door/window switches, motion detectors, stick-a-switches, etc. which have notoriously short range. While the FCC prohibits any modification of the antenna on a transmitter and several X-10 receivers have electronics that use the hot side of the mains as electronics ground (making it dangerous to make changes to the receiving antenna which is OK with the FCC), there is still something that can be done to improve the operation of these wireless systems using the ancient Chinese art of Feng Shui to improve the qi or energy flow1 of the system.

The concept is illustrated below. By properly aligning a short length of wire (passive radiator) at each of the wireless transmitters, the system energy flow is increased. You may need to experiment with the wire type, length and orientation. I found an 18" length of solid steel coat hanger wire worked quite well and I could not see much difference in energy flow from a few experimental orientations; it just needs to be close to the transmitter. While I've illustrated the concept using the SS15A, I've tested door/window switches and similar X10 transmitters with equally good results.

To counter negative energy flow from members of the household more interested in upholding appearances than in exploring ancient Oriental mysteries, you can drill two holes in the dry-wall, insert the ends of the wire and plaster over the holes.

Conductive tape would likely work as well as a wire but I do not know whether paint will adhere to it.

Using an RF receiver with a linear (analog) output and an ADC pin on a microcontroller, I have made comparisons using door/window switches and motion detectors with and without passive radiators and observed a doubling or tripling of received signal strength at the receiver 25-30' away.

Some CM15A users have reported range improvements by taping an 18" length of stiff wire parallel to the CM15A antenna, aligning one end with the base of the existing antenna. One user's range tests using an SH624 remote gave over 200' with a 1/2 wavelength (18") wire on the remote and a standard CM15A. He got 120' with a standard Sh624 and an 18" wire added to the CM15A.

1. A modern sceptic, with access to an electronics lab, measured an omnidirectional increase in qi of 10dB.

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