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