I took your advice and purchased a TT BlacX and a WD20EURS. Haven't connected it yet but I understand your sequence to connect it. Now I still have some old recordings on the internal drive I need to watch but I would like to see that what I bought will work so I would like to connect the external, try it, and then remove it. What would be the best sequence to power down and remove the external and use the internal again? Thanks for your reply!
First time you do it, unplug the HR and don't plug the dock in yet. Attach the eSATA to eSATA cable to the HR and then, with the HDD in the dock, plug in the power cord. Wait until the HDD is thru spinning up, you can hold your hand on the top of the HDD and feel it spin up and "burp" when it's done. Then plug in the HR and it should recognize the external HDD. You will see a window on your TV that says the HR is checking your storage device, or words to that effect. Believe RunnerFL when he says the on/off button on the back is fragile. Once you initially use it to turn the dock on, don't use it anymore, pull the plug.
After the first installation, follow RunnerFL's instructions on rebooting. Doesn't work every time, but it does most of the time. If it doesn't work, go back to my original instructions.