LampLinc 2000STW - mystery solved

[nobody@xxxxxxxxxxxx (Dave Houston)]

I bought one of these when they were first introduced, placing my order
before they were shipping. I then posted here that I was disappointed
because it would periodically go deaf to the powerline while randomly
flashing its LED. An LM465 & LM14A in the same circuit performed flawlessly.
Using my scope card and ACT Scope-Test2, I could see nothing on the
powerline to explain it but still suspected there was some noise (outside
the Scope-Test2's bandwidth) that was bedevilling the 2000STW. (I've seen
periodic reports from others that they've seen the same thing with this and
similar LampLinc modules.)

At the time, SmartHome asked if I'd be willing to be a beta tester and
offered to replace the 2000STW and give me two more. I declined, saying that
my health was too iffy to guarantee I could give it the time warranted. They
replaced my 2000STW and gave me two more, anyway. All did the same thing but
were OK if used in other circuits so I've been using one with a bedside lamp
since then with only one glitch - a couple of weeks ago a brief power outage
caused it to lose its address.

Recently I tried the others again in the circuit that had given them trouble
and they were OK. In the interval between the original and the latest trials
I had given one of my PCs to a niece who was moving out of town. My guess
was that the power supply on that PC was the culprit.

Yesterday, while experimenting with various lamp modules (See the X-10 Dims
thread.), I dug out the unused 2000STWs. They were again OK.

This morning, they both exhibited the deafness and flashing of the LED
(although its now constant instead of random). Again, an LM465 and LM14A
perform flawlessly in the same circuit.

A few days ago I wiped out my printer and had to order a new one. The new
one has a switch mode power supply. The 2000STWs are fine when in a circuit
isolated from the printer.

I think the 2000STW is overly sensitive to out of band noise.