X-10 RF troubleshooting

["Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>]

For a while last night, I thought Bill K. might be right - X10 is junk!
(*(_*#^&^^ rotten stinkin' JUNK!!!!!

In the last few days I noticed, in this sequence:

The light on my RF-sensing pen started to flicker constantly, not in its
usual random pattern.  This was promotional item I got at some show that
lights a diode whenever it detects cellphone EMF nearby to let you know your
cellphone is ringing by eye.

Then, the Powermid IR unit in the LR would not control the AV stack but
direct control and control of the AV gear from the kitchen was still
possible.

Finally, almost everything stopped working, especially RF remotes.  Local
control was still available, and close-by controllers worked close-by
modules.  The Monterey showed a steady stream of P1 OFF's - P is the code
for all the PalmPads.

So while other people were hunting Easter eggs, I lashed my ESM-1 to a TM751
and plugged them into a long extension cord and began hunting for stuck
transmitters.  The ESM1 varied wildly as I moved about the house and changed
the orientation of the antenna relative to the case.  I finally found the
problem - out of the corner of my eye I saw a blinking red LED when I turned
the lights out. The ESM-1/TM751 combo had led me to that area, but not right
to that spot.  It was the same as before - a stinkin' &&^$# PalmPad got
wedged under a keyboard in the PC room.  I had previously searched that area
pretty closely using the AM radio technique and found nothing, FWIW.

I thought that the PLC signal strength might be affected by the RF signal
strength, but that turned out not to be the case.  I think with the TM-751
sitting so close to the ESM-1 on the extension cord (they're back to back,
connected by rubber bands to hold the meter head in place) I was seeing some
sort of inductive coupling.

But I also noticed something much more interesting.  When hunting a known
test item in a known test location I found that I could use doorways to form
collimating slits.  The walls are old lead-based paint over wire lathe
plaster --   :-(    -- RF barely penetrates.  But when I position the
Palmpad somewhere where it's visible to the naked eye, the ESM-1 clearly
indicates any deviance from that line of sight.  As soon as there's a wall
between the TM-751 and the Palmpad, the signal vanishes.

This is at least the third or fourth time there's been a "stuck" transmitter
button.  The ESM-1 is useful in tracking down the stuck Maxicontroller
keys - the closer you get, the higher the signal level - but so far tracking
down the RF "stuckees" has been rather more difficult.  It would be nice if
I could build a cheap X-10 RF signal strength tracker.  Even a simple
direction finder would be nice. I guess I can find an old coffee can and run
some tests.  Problem is, we don't drink coffee anymore!

--
Bobby G.