Re: Compact Fluorescent Noise

[nobody@xxxxxxxxxxxx (Dave Houston)]

"Jeff Volp" <JeffVolp@xxxxxxx> wrote:

>One other thing I noted while looking at the scope photos is that timing of
>X10 bursts at other than the zero crossing is not well defined.  Please look
>at the following two photos:
>
>http://jeffvolp.home.att.net/x10xmtbuf/linenoise1.jpg
>
>http://jeffvolp.home.att.net/x10xmtbuf/linenoise2jpg
>
>Notice how the X10 bursts move from one sample to the next.  Also note the
>zero crossing burst is fixed as is the line transient just after the center
>zero crossing.  That third burst moves just about 1mS, and I don't see how
>it could hit the reception window in a three-phase system.  Signals were
>transmitted from a RR501 in response to a palmpad.

I've never seen that and I've looked at a lot of scope traces from various
X-10 devices. In fact, I've always been rather impressed that the 120kHz is
really 120kHz and other timings are near right on using 30 year old LC
technology. For some examples, take a look at the screenshots in this
link...

     http://davehouston.net/x10-sig.htm

My pseudo-scope measures frequency and amplitude of a signal, making some
measurements fairly easy.

I suspect either that you have an erratic RR501 or there's something amiss
in your setup or that your scope has rheumatism.

It sounds like a neigbor has an intercom or baby monitor.

http://davehouston.net
http://tech.groups.yahoo.com/group/roZetta/
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