Hi Bruce, Though I am not sitting there, I feel the Toolkit is dropping out just as the Minder is periodically sending Hayes Modem reset strings to initialise a modem it 'suspects' is there. Toolkit isn't expecting that on a PCI. If this is the issue, you can attach hyperterminal etc to it in terminal mode and you will see ATZ ATS0=2 ?+++ATH etc 'The serial port output you are seeing are modem control strings as the Minder thinks it is talking to a modem to allow remote access. ATZ reset the modem to factory defaults, ATS0=2 sets a modem to answer on the second 'ring', +++ sets the modem to 'command state' and ATH hangs up waiting for call. Look for 'AT modem command' or 'Hayes modem strings' on Google for more info. ' See [URL]http://www.cbusforums.com/forums/showthread.php?t=7223&highlight=hayes[/URL] for more detail It could also be: 1. Like Mr Mark says, the PSU has too much voltage on the c-Bus making the c-Bus comms AC waveform transmitted 'on top' of the DC voltage get 'clipped'. 2. A burden is not present or the capacitor is old, dry and dead. Use a new burden or enable one in the relay you showed pictures of. Remove the other one. As for the Minder programming, I wanted to give you a taste so you know what you are in for. If you are looking for an all consuming holiday project, then this is it!!! :D See attached JPG 1 :- from the training manual. Note well the 'Experience' piece of the pie chart and also the line 'Everything that the HomeMinder is required to do must be programmed in explicit incremental terms a line at a time'. Still makes me shiver!!! :p Next is JPG2 - a copy of what YOU need to write just to get one small part of the program working. This is pg93 and the 'demo program' fills full pages to page 111 (though you can use the demo as a template to a degree) Save yourself the PHD and purchase a newer logic unit. You'll thank everyone and yourself!! Wisers are my favorites as you get so much in one box (including iPhone and iPad local/remote house control) but everyone's cottoned on to that now and so demand is hugely outstripping supply. Happy to help. PM me for a time. Regards again, Brad