I started with a 64GB memory stick, which worked, but was not fast enough to record at the same time as playing a previously-recorded program. The TV repartitions it in such a way that I couldn't use it on a PC again - I can't restore it to a working 64GB stick using the Windows OS software. It may be possible with Linux - I'm not that familiar with it - but beware, if you plug a memory stick in, you can throw it away when you unplug it again.
Then I plugged in a 160GB disk drive that came from an old desk top PC (It's an IDE drive that I put into a USB chassis). It works fine, but the TV software doesn't work properly, and Sony has no interest in fixing it - apparently no interest in keeping its customers happy. Here are the problems:
1) As stated above, a USB stick works (to a degree), but becomes a throw-away item when you disconnect it (although it will still work as before in the TV)
2) TheTV has two lists of programs, the "Timer list", which stores the titles of programs that are scheduled to be recorded (but which have not yet been broadcast), and the "Program list", which lists the programs that have been recorded.
The Timer list contains the correct program titles that you selected for recording, but they are not carried through to the Program list. Here's what happens. You want to record Columbo - a detective series in which the clever stuff is revealed in the last 30 seconds of the show. It comes on at 10PM. You select it from the program scedule, and the Timer list shows : 10PM: Columbo - 60 minutes.
At 10PM, the TV switches on, but the previous program, "Master chef competition final", in which you have no interest, has overrun by 2 minutes, so it is still on when the timer starts recording. The Program list (where you select the program for viewing) says "Master chef competition final - 60 minutes". When you view it, Columbo starts after two minutes. 58 minutes of recording time to go - so when the timer switches the recording off, the program still has two minutes to play, and you miss the clever ending. I miss the ends of programs and films time after time after time, and I'm sick of it. This is NOT unavoidable. If I could get hold of the source code for the processor that handles recording, I could fix it - but Sony has no interest in that - presumably because there's no money in it. Existing customers pass on the word. I wouldn't advise anybody to buy Sony!
Incidentally, if you wanyt to use the hard drive on a PC again later, you CAN repartition it using the Windows OS - although while it's possible, it's not straightforward.
