Alternate
Method for Aligning ReceiversCredits: )) Sonic ((
http://siber-sonic.com/X10/X10world.html
Most X-10 devices have one or more internal
adjustments, most commonly related to the powerline carrier (PLC).
Modules typically have one transformer to optimize the reception of the 120kHz PCL signal.
Old-style modules also contain a frequency adjustment for the IC.
The simpler controllers typically have both frequency and amplitude adjustments which
affect the 120kHz PCL signal. More complex devices such as the RR501 transceiver may have
4 or more adjustments.
One may well ask, “Aren’t X-10 modules
correctly aligned at the factory? Why bother adjusting them?” Well, first of all,
given the low price of most X-10 modules, not every one of them may have been optimally
adjusted at the factory. Second, the transformers which couple the 120kHz PLC into and out
of the A.C. powerline are affected at least slightly by the particular impedances of the
particular wiring and connected devices at each particular location in each of our homes
(and wherever else X-10 devices may be used). Thus, marginally-triggering modules and
controllers may both perform more reliably when adjusted to their particular locations.
The alignment procedures on these pages take these considerations into account.
After aligning the controllers and modules with
the procedures described, AND cleaning the circuit breakers and their busbar and wire
connections with Cramolin® R5 spray cleaner, the CP290 now reliably controls these
modules, and indeed everything in the 2200 sq. ft. house and detached garage. Same with
any combination of the other maxi- and mini-controllers, Sundowners, etc. with any
modules.
In all honesty, while the alignments did noticeably improve the situation, the cleaning
was essential for consistently reliable operation. Note that only two years prior, i had
cleaned ALL the breakers/busbars/wires with Cramolin® R5. It cannot be overstated how
important it is that all electrical connections throughout the structure are clean and
tight for proper X-10 operation!
Not all wiring systems propagate 120kHz signals equally well, and it seems that the X-10 system, reasonably enough, is designed for homes wired with NM cable (often called by the trade name Romex®) or wires in conduits. Old homes with open Knob and Tube wiring are likely to experience greater reliability issues, since the far greater spacing of the conductors will present a very different impedance to 120kHz signals intended to traverse closely-spaced conductors.
Connected a clip lead to the stereo AM antenna
terminal and laid the free end between the transformer (T2) and the chip. (loose coupling)
Tuned T2 till I heard a carrier on the stereo.
BTW: I then tried this on a untouched IBM mini controller and heard the carrier without
any T2 adjustment. Which leads me to believe that at least that one was properly aligned
at the factory. This seems like it would be a good quick and dirty way for folks without a
counter to get those transmitters aligned.
In each individual alignment procedure, i will mention
isolation devices as i used them with my equipment. It is up to you to modify my
instruction to pertain to your particular equipment. Depending what you have, you may not
need isolation where i needed it, or vice-versa. Proceed with caution!
Basic
adjustment outline for the entire X10 system
Transmitter amplitudes needs to be measured in
some way away from the module, to minimize the interaction of the test equipment. The best
solution i found so far is to connect the test equipment via an isolation transformer. In
the future, i hope to provide a schematic of a full-fledged X-10 alignment box at siber-sonic.com. Until then, i leave
you to your ingenuity as to how you will safely measure the PLC output on X-10
controllers.
For the purposes of these alignment pages, i will already
refer to whatever 120kHz sensing arrangement may be used as the “powerline signal
sensor”.
In some cases, the PLC frequency will be measured from the powerline signal sensor, just
as for the amplitude. This will usually be in cases where it is possible to generate the
120kHz carrier without the X-10 data stream modulation. In other cases, the 120kHz
carrier, or some clock multiple thereof, will be measured directly on the device being
adjusted, where this can be done without detuning the oscillator!
PLC amplitude in receiver modules will be
measured within the module. It will be necessary to attenuate the output of a
previously-aligned (for correct frequency, at least) controller sufficiently to put the
received signal below the diode clipping amplitude, yet large enough to see above the
noise reliably. It would be very convenient to have a modified controller with
continuously-adjustable output amplitude. Having not thought of that as i was developing
these alignment procedures, i connected the controller to a long extension cord (15 to
30m/50 to 100') and adding/removing loops and/or changing to other circuits to obtain a
reasonable amplitude.
Example alignment procedures are in the respective module modification section.
Alternate
Method for Aligning Receivers
You will need just a scope for this procedure.
Open the module and hook up a scope at the
output of the impedance matching transformer. This is the leg that is farthest from the
edge of the PCB and closest to the large electrolitic capacitor in an appliance module, as
shown in figure at left. The setup should be close as possible to where the receiver will
operate 
Operate a transmitter to continuously send ON to HouseCode M, Unit Code 13. The best way is to program an endless macro or something similar.
Set the scope to 200mV/Div, 200mS/Div, trigger on Line, and connect power to the module. Be careful, the module is live, don't touch anything with your hand.
While the transmitter is transmitting, use a small isolated screwdriver to tune the transformer until the maximum amplitude is reached. I was able to get about 400mV of signal.
The scope screenshots below show the difference between a poorly tuned transformer and an optimally tuned one.
