Now that I've looked at the manual for the DX Doubler from Top Ten Devices and the Manual for DX4WIN 6.01 I think I see the problem with SO2R operation. The DX doubler uses pin 17 on the LPT port for CW keying (High state to key transmitter) and DX4WIN 6.01 uses pin 20(DTR) for CW keying. As it stands even if I have File|Preferences|Control|CW Keyer Interface set to "NONE" the radio selected is keyed as soon as it is selected. Both DX4WIN 6.01 and the DX Doubler SO2R box use LPT pin 14 for "Radio Select", so that works fine. The DX Doubler works correctly with Writelog and is advertised as being able to work with CT, NA and TRLog. I know at one time there wasn't as standard for some of the LPT pins. I don't know if there is one now. Hopefully, if I'm not missing something, the new DX4WIN program can also be made to use pin 17 for CW Keying.
Roger, W1EM
