At 10:40 PM 5/14/2003 -0500, you wrote:
>many home-handy devices (like X10 and other remote-control units,
>From the X10 web site: <http://www.x10.com/support/technology1.htm>
(and edited quite a bit)
"X10 powerline carrier transmissions are synchronized to the zero crossing
point of the AC power line. The goal should be to transmit as close to the
zero crossing point as possible, but certainly within 200 microseconds of
the zero crossing point. The maximum delay between signal envelope input
and 120 kHz output bursts is 50 ?sec. A Binary 1 is represented by a 1
millisecond burst of 120 kHz at the zero crossing point, and a Binary 0 by
the absence of 120 kHz."
With the 135Khz spacing that WB5JNC is having, we are a bit more than 10%
off. Maybe good enough for the signal to work but it might start getting
intermittant for some of the devices on the system. The other thing that
would steer me away from this is the very low duty cycle. It only has data
when there is something to send and then it only transmits its 120Khz burst
for 1ms at the zero crossing.
The X10 devices would be lower on my list than someones PC switching supply.
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