Good question! I did a serial loopback test right at the 9 pin port and it passed. I added the 9 pin female adapter and did a loopback test after the adapter was inline and it passed the loopback testing I then added in the cat 6 cable with the RJ45 connectors and did a loopback test at that end. It passed too. So essentially I tested after each device and tested all the way thru from the serial port to the Tech 2 side and everything passed. BTW - I did buy a new Belkin cat 6 RJ45 cable and also made my own cables to test. Each one passed all the testing. I also bought a female 9 pin connector that you can easily change the wiring on the pinouts just in case I had a conductor connected to the wrong pin. So far the serial cable i have is correct. The pinouts are: (RJ45 to DB9) 1-6, 2-1, 3-7, 4-2,5-3, 6-8, 7-5, 8-4 If anyone has a different pinout, please let me know.