Interesting ACT CR230 repeater failure mode

[ddl@danlan.*com (Dan Lanciani)]

I recently tracked down some odd behavior with my X10 equipment.  It
turned out that my CM11a was not seeing certain status responses.  In
particular, the response from an ACT RS104 (which normally consists
of its own unit number followed by status_is_on/off) consistently
contained only the unit number.  The responses from various PR511
(status_in_on/off only) arrived intermittently.  Looking back through
my log files I found that the problem had first appeared several months
ago with intermittent reception of the RS104 response and eventually
built up to consistent failure.

Disabling the CR230 repeater made the problem go away.  X10 being what it
is this isn't dispositive, so I ordered a fresh CR230 to swap in.  It
arrived today (I was disappointed that it still doesn't carry a UL logo)
and installing it did not cause the problem to return.  So I'm pretty sure
this is a CR230 failure.

Superficial examination of the suspect CR230 shows the characteristic
blackening around the hot zener, but nothing obviously damaged.  (If
I were guessing I'd say it might be the adjacent filter capacitor which
is only an 85C part and is clearly subject to a lot of heat from the
zener.)

I tried to mail Phil Kingery but his address at ACT goes to the intercept
that says they don't support PLC products anymore.  Is anyone interested
in more detailed analysis?  I wouldn't normally be inclined to bother--
especially with ACT apparently getting out of the business--but the effect
of corrupting (apparently only) status responses seems oddly familiar.

				Dan Lanciani
				ddl@danlan.*com