RE: Re: xPL/xAP an alternative to C-Bu$ ?

["Kenneth Watt" <kwatt@xxxxxxxxxxxxxxx>]

> (contentious night tonight :-)

It's fun though. ;)

> There is nothing wrong with power line control per se, you just have
> to do it right.

Agreed, but that means all new products, with licences and development
costs
you'd probably be more expensive than X10 is especially on low volume
production.

> The X10 protocol was devised over twenty years ago, and built to a
> price that could be achieved back then.  The designers chose a
> simple encoding, low baud rate, with no form of error checking.

Yes, which has survived for all this time and in fact thrived and grown as
well a spurned a whole generation of automation products that may otherwise
have never have seen the light of day. It got people interested and it does
the job, if not as perfectly as some would like.

I should imagine that two factors drove the development as they always seem
to do, price and what could be done at the time. When X10 was developed a
PC
in every home was a pipe dream, Laserdisc had just been invented and CD was
a new thing to the market at gross prices. A PC that was considered state
of
the art for the home was a ZX80, by comparison X10 has done well to survive
as it has done simply because it's cheap, simple and easy to use.

> Technology today supports broadband ethernet over powerline, which
> has a much greater data rate, and higher requirements of data
> accuracy.  It can be done.

Yes it can be done, but remember your remark about it being twenty years
old
and also bear in mind that for most people's *HOME* automation needs it is
actually just fine.

> I agree.  But when I slag X10 as a poor relation system (which is
> nevertheless a system I use personally) everyone wants to tell me
> how great it is.  If its so great why cant it be compared to a bus
> system?

Because a bus system has its own dedicated wire to transmit commands along
which should, if the installation is correct, be free from any external
interference and X10 is not afforded that luxury in that any old vac or
transformer that's plugged in could potentially cause a problem.

K.