Re: Water heater eating X-10 signal

[nobody@xxxxxxxxxxxx (Dave Houston)]

"Robert Green" <ROBERT_GREEN1963@xxxxxxxxx> wrote:

>What happens if you move the ESM1 meter head near the transformer, as in
>mounting both the head and a power supply inside the same box and having
>just a line cord extend from the unit?

>What would happen if I recorded in MP3 and converted back to WAV format?
>would the loss be noticeable?  Disk space wouldn't be as much of an issue
>that way.

I tested the effects of the wall transformer on the meter extensively when
the ESM1 was introduced (and my review here savagely attacked on those very
grounds). I found no effect. My test setup usually has the wall transformer
in a powerstrip on a work bench with the meter sitting atop the transformer
and my Scope-Test2 or other filter plugged into the same powerstrip.

I have no idea how lossy MP3 might be in this case. I use Loop Recorder for
tests like these and it only records .WAV files. All I can suggest is that
you experiment.

Until I test it I don't know whether the soundcard will record the higher
frequencies that are beyond the audio range. Since we're sampling at a rate
well below the Nyquist limit, we'll see an aliased noise signal if it's not
filtered out first. My Audigy soundcard can sample at 96Kb/s (although Loop
Recorder does not go that high) but higher frequencies may be filtered
before the sample is taken. This is, after all, a $1.98 solution (1 audio
cable, 2 resistors) which, while it may not be the ultimate piece of PLC
test gear for all conditions, it should prove useful to anyone who already
has the ESM1.