The TW523 and PCS-05 are identical - the only difference seems to be the price.

The PL513 and TW523 are detailed at http://software.x10.com/pub/manuals/technicalnote.pdf. The PSC-O4 and PSC-05 have the same details.

The diagram showing how to connect your OEM product is a little confusing until you understand that everything outside the OEM product is internal to the PSC-05. Specifically, the optos are internal to the PSC-05.

Refer to [b]Typical OEM Connection diagram (p11). All you need is a pull-up on your X10 signal (to the PSC-05). You really don't need to invert the X-10 signal from the PSC-05 as you can handle that in your program logic. The clamping diodes and the 100 ohm current limiting resistor are overkill.

I don't have access to my PBP manual, as it has been in a storage unit since my lengthy stay in the hospital last year , but as best I recall, it shows exactly what you need.

X-10 is being cautious as the same basic approach is used for both 120VAC and 230VAC. The optos protect you and your circuitry should something go amiss within the PSC-05.

Bruce, Anand Dhuru and mackrackit can all advise you on the specifics.