SmartHome 4826B coupler-repeater loses all dimming

[cactusjack]

My X-10 system using ActiveHome Pro worked satisfactorily except for one 3-way Lev-6383. I purchased a SmartHome 4826B coupler-repeater to strengthen the system. It controlled everything beautifully with strong signals as measured with a test set. However none of the modules responded to the dim setting. What am I missing? My home is 5000 sq. ft. and I do have a 0.1mf capacitor coupling the phases at the breaker box.

[JeffVolp]

Bright/Dim commands are a special case for repeaters.  X10 signals are normally sent twice in the same message.  Most repeaters take advantage of that by receiving a command during the first half, and re-transmitting it in exact sync with the second half.  This works for most commands where a module only needs one valid copy to take action.

Bright/dim commands work differently.  There are normal bright/dim steps, which will slew the dimmer from full-on to full-off in about 16 steps.  Then there are micro-dim steps, which take over 100 from full-on to full-off.  Unfortunately, the X10 protocol uses exactly the same command for both.  The only way the receiving module can tell them apart is how they are strung together.

Normal bright/dim commands are sent in sequence with no gap between.  A sequence of several bright/dim commands sent that way will ramp a light quickly.  The repeater messes up this sequence by only repeating the second half of each bright/dim command.  So those bright/dim commands are recognized as micro-dim steps by any module that does not receive the first half.  Some repeaters have a fix for this, and it is one of the special cases I am trying to handle in the repeater version of the XTB-II.

A suggested fix is to move your transmitter closer to the main distribution panel so the modules stand a better chance of receiving the first half of the bright/dim message.  If that is not feasible, you could use a booster to directly increase the transmitter output.

Jeff

[Walt2]

I bought one of the 4826B's, and ended up returning it.

The 4826B also doesn't seem to support 2-way modules either, and will "hang" in a continuous repeating of powerline commands, over and over again, until you unplug it.   

Check out Troubleshooting Automation Problems -- Phase Coupler/Repeater, plus other similar postings (search on "4826B").