Here’s an extremely handy tool if you’re installing and troubleshooting X-10 equipment. Just plug it in and it measures all sorts of attributes of the powerline signal and background noise. It allows you to track down weak X-10 signals, high noise levels and it will also dissect the X-10 codes into their bit by bit components and keeps a running history in memory to boot..

X-10 CODE IDENTIFIER & SIGNAL STRENGTH ANALYZER – All 256 X-10 unit codes and the 16 X-10 function codes can be displayed. The Analyzer will display the signal received an example would be E-12 E-On. To indicate a corrupted signal the display would read bsc (Bad Start Code). This simplifies identifying code transmissions and diagnosing faulty transmitters. To check a transmitter simply plug the unit in and push the transmitter button. The Analyzer should display the correct code and the signal strength. Just performing this simple test will tell you if the transmitter is sending the correct code, that it is a clear code and that it is a strong code.

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The signal strength, measured in volts, is displayed underneath each corresponding X-10 code received. As an example you may receive an E-12 with a strength of 89m (Milli Volts) . Because the signal strength is measure in milli volts it is very easy to see the effect of other devices.

POWERLINE NOISE INDICATOR – Strong electrical “noise” on the AC power line can interfere with X-10 transmissions. X-10 codes are placed on the AC power line at a frequency of 120 Kilohertz for a duration of 1 millisecond after each zero-crossing of the AC Power line cycle. The Analyzer will identify noise over 100 Kilohertz and indicate the strength of the interference. The analyzer takes two different readings for noise at the zero-crossing one is at .5 milli seconds the other is between .2 and .9 milli seconds. This is a very valuable tool to assure any installed filters have diminish the interference to acceptable levels.

X-10 SIGNAL DISSECT – This is an extremely powerful tool allowing you to analyze X-10 protocol. Each X-10 code is always transmitted twice using 22 AC power line cycles. Each true bit of code information is transmitted at the zero-crossing point with a compliment bit transmitted on alternate half cycles. All 22 true bits of X-10 code and their compliments can be viewed. You can actually dissect the E-12 E-On down to 1s and 0s bit stream. This is helpful with diagnosing boosters and repeaters. This also allows you to see extended X-10 data codes for preset, hail acknowledge and others.

HISTORY – Up to 190 X-10 events can be recorded and stored into non-volatile memory to be played back at a later date. The Analyzer stores the identity of the received X-10 code, it’s signal strength and the elapsed time from the start of recording. This is another powerful tool allowing you to verify macro events and also identify spurious and bothersome X-10 signal at odd times.

I found the unit very easy to learn and operate. Just plug into the outlet you want to analyze and use the 3 buttons on the face to display the data you need. The “Mode” button let’s you select one of 5 modes by pressing it the prescribed number of times. Don’t worry if you forget which mode is which … they’re written on the front of the unit. The modes of operation are:

* Mode 1 – Code Identifier and Signal Strength (volts or millivolts)
* Mode 2 – Power Line Noise (millivolts)
* Mode 3 – Signal Dissect
* Mode 4 – Record History of Events
* Mode 5 – Reset History Log

The “Back” and “Next” buttons allow you to scroll through the history. This display gives you a listing of how many codes were recorded, the number of the event being displayed, what the code was, it’s signal strength and the number of hours since the History was reset.

A handy table on the back of the unit lost what all of the display abbreviations mean and the bitcode values for dissected X-10 codes.

The unit is small and easy to handle. It comes with a nice carry bag and a short but complete set of instructions. I guess my only concern with the unit is that the mode buttons are a bit flimsy mind you they are very sensitive and responsive.

The Power Line Signal Analyzer is available from Custom Home Control for $349. They may be reached by email at or here’s the address.
43055 Camino Caruna Temecula, CA 92592
Phone Office & Fax (909) 506-2329