Re: X10 replacement?

[Marc_F_Hult <MFHult@xxxxxxxxxxxxxxxxxxxxx>]

On Tue, 03 Oct 2006 20:28:44 GMT, Joerg
<notthisjoergsch@xxxxxxxxxxxxxxxxxxxxx> wrote in message
<0KzUg.12961$7I1.2600@xxxxxxxxxxxxxxxxxxxxxxxxxx>:

> But even then it is a rather brazen assumption that
>the loss along a power line would be less than 40dB or that the noise
>won't swamp everything, unless there is a proper passband filter. One
>that is only a few kHz wide and not tens of kHz.

Who is making this assumption ?

At the transmitter end, and at the receiver end, there are low-current
improvements that are practical in part because they involve physically small
devices with concomitantly manageable costs. Here, the filters only need to
pass the signal. not, generally, high current. And if they do, the current
may be reduced (eg 5 amps as in a wall-wart filter) compared to the in-wall
AC distribution lines (15, 20, 30 amps).

As soon as one moves from the device level to the realm of permanently
installed transmission medium which in US and Canada, is 110VAC is subject to
electrical codes that (for permanently installed components of the
transmission system) require a *minimum* 15 amp current-handling capability)
the problem becomes quantitatively much different.

How does one make a (c)UL-listed, low cost, 15+ amp, 120khz, multi-pole notch
or bandpass filter ? If one can't, then the notion that robust distributed
X-10 can be low cost is myth.

Lightolier introduced the concept and sold the Compose PLC (X-10) system
based on large, expensive hardware to filter and segment the home AC
distribution.

http://www.lightolier.com/index.jsp?FLASH=1&FL=releases/PRComposePLC.htm&A=208&B=233

It was (see this thread's subject) an evolutionary "X10 replacement".

My limited perspective is that it seems to have had a short run in the
marketplace and then seems to have mostly declined. I don't have any
experience with it. Maybe someone in c.h.a else does and can pipe up.

>Many times X10 works ok, other times it doesn't. The worst case is when it
>sometimes does and then quits. That drives ordinary customers nuts,
>especially when they do  not understand why.

It also drives  folks who _do_ understand to rip it up and install something
"more reliable" (whatever that might mean ;-) Knowing that and *why*
something doesn't work can also be a powerful driver to removing it. Depends
in part on one's mindset.

Thanks for the cogent discussion ... Marc
Marc_F_Hult
www.ECOntrol.org