The next screenshot shows the signals on pins 13 & 18 of the ESM1's PIC. The ESM1 is a low voltage device and is isolated from the powerline by its 12VAC transformer.

The following screenshot is of a .WAV file recorded with a soundcard connected to pins 13 & 18. This was with no attenuation on either channel other than setting Line-In volume to midscale in the mixer control. The sampling rate was 8000 samples/second. I used Loop Recorder to record it and GoldWave to display it. The screenshot is from GoldWave.

EXAMPLE.WAV is a short wave file with X-10 PLC sequences you can download and view in a wave editor.

The ESM1 schematic below was drawn by John Galvin soon after the ESM1 was introduced. I added the dashed lines to show connections to make to create outputs that can be recorded as .WAV files using LINE-IN on a soundcard. In my case, I cut about 8 inches from the female end of a 3.5mm M/F extension cable. I stripped about 3 inches and connected them as shown in the schematic.

DO NOT USE ANY SOUNDCARD INPUT OTHER THAN LINE-IN. USE AT YOUR OWN RISK!

Here's a picture showing the connections on the bottom of the ESM1 printed circuit board.

Prudence suggests the signals to both soundcard channels should be attenuated to guarantee they do not overload the soundcard. The voltage divider shown below will do this - one is needed for each channel. If your soundcard mixer has a Line-In volume control you can adjust it to accomplish the same thing. Start with it set to minimum and increase until the strongest signal is just short of maximum on the wave editor display.

There are freeware and commercial software packages that allow using the soundcard as an oscilloscope. This allows you to make amplitude adjustments in realtime before recording to a wave file.

http://www.electronic-engineering.ch/microchip/software/soft.html
http://www.zeitnitz.de/Christian/Scope/Scope_en.html
http://www.zelscope.com/
http://www.virtins.com/page2.html#Oscilloscope

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