Re: x10 Help

["Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>]

"Dave Houston" <nobody@xxxxxxxxxxxx> wrote in message
news:46fcd37d.3058850734@xxxxxxxxxxxxxxxx
> "Robert Green" <ROBERT_GREEN1963@xxxxxxxxx> wrote:
>
> >If you're going to continue with the XTB, you'll need to recalibrate the
> >unit to match its much higher than normal output.  I would just set it so
> >that the signal at an outlet farthest away from the XTB shows a few bars.
> >What you really want to know is relative, rather than absolute signal
> >strength.  If it shows a few bars at the very end of a circuit, it should
> >still be able to register a drop if you put a new device on the line that
> >turns out to be a signal sucker.
>
> I would not calibrate it to the XTB as you will then be unable to see
> signals that, while low, are still more than adequate to trigger an X-10
> receiver.

Why would you care about low, unboosted signals like that?  If you plug
something like that into the outlets of a house with an XTB-II in the
repeater mode, it's going to boost the signal.  If you wanted to measure the
output of those low output devices accurately you would have to place them
behind an X-10 filter to keep the XTB from seeing them.

It makes more sense to me to find the weakest XTB boosted signal you can
find and make sure that it shows up on the meter as a few bars.  If a signal
sucker finds its way on line, you'll be able to see its effects easily.  I
agree that in most cases you will care more about the weaker devices than
the stronger ones, as you say, but with the XTB-II installed the signal of
most things in the house is likely to "bend the needle" at the max end of
the ESM1 bargraph LED with no discrimination.

Setting it so that it registers the weakest signals in the house as a few
bars will likely mean that most normal transmissions in the house occur
within the bargraph's display range, which is what I would want to have from
a meter.  The way the ESM1 flickers it's not likely you're going to get a
precise voltage reading anyway so it makes sense to calibrate it so that it
registers the highest and lowest signals somewhere on the scale.  The
difficulty in all this is that you're trying to read from 0 - 20+ volts with
meter only designed to read from 0 to 5.  That implies a compromise
somewhere along the line.

It all really depends on how he plans to use his meter.  Will he use it to
check for signal suckers?  Noise?  Relative signal strengths?  Jeff's
suggestion of adding a filter ahead of the wall wart would work, but it
makes the meter into more of a bolo than it already is and makes it a lot
harder to fit into tight outlet spaces.  It's probably pretty easy to add a
small switch with a fixed resistor to provide two scales, one high, one low
and if I didn't have the Monterey, which reads accurately from 5mv to 4
volts, I probably won't bother dual scaling the ESM1.

--
Bobby G.