Re: Water heater eating X-10 signal

["Jeff Volp" <JeffVolp@xxxxxxx>]

"Dan Lanciani" <ddl@danlan.*com> wrote in message
news:1338672@xxxxxxxxxxxxxxxxxxxxxx
>
> Jeff has suggested that signal sinks can reduce the signal as seen at
> the panel/repeater (either by taxing the repeater's power supply or by
> causing a drop across its output coupling network).  I've never seen this
> happen in practice, but it could provide a mechanism for non-local
> effects.

XTB-II output with no load is over 40Vpp.  The measurements I made here last
year with the XTB-II connected to the main distribution panel were 25Vpp on
one bus and 30Vpp on the other bus.  Since the driver is common, that has to
be drop in the coupling networks.  One leg must have somewhat lower
impedance than the other at 120KHz.  The leg that read the lowest was our
non-X10 phase with the "unfriendly" loads.

In a recent test, I measured the XTB-II driving 30Vpp into a 5 ohm resistive
load.  Increasing the load pulls down the 6W unregulated supply.  Obviously,
more power is delivered as the load impedance decreases.  But the lower
power supply also decreases the Vpp delivered to the coupling networks.

Jeff