It's also possible to unlock this recorder, and indeed most recent sony machines using a laptop with an infra-red port.
I know because I have done it!!
The info below is copied from another source, but please read my notes below that.
1. Download the winsamp -package from Blank Franks site.
This innovative piece of software allows you to send standard home electronics IR signals using a PC IRDA port.
2. Extract the package onto a bootable DOS floppy disk.
3. Save the following code into a file named "REMOTE.TXT" and put it in the same and place it in the same directory as the package above.
"Sony Region Free Code 1",84,24,6,12,6,12,6,12,6,12,6,12,6,12,6,12,6,6,6,12,6,6,6,12,6,12,6,12,6,6,6,6,6,12,6,6,6,6,6,12,6,6,117,24,6,12,6,12,6,12,6,12,6,12,6,12,6,12,6,6,6,12,6,6,6,12,6,12,6,12,6,6,6,6,6,12,6,6,6,6,6,12,6,6,117
"Sony Region Free Code 2",84,24,6,12,6,6,6,12,6,6,6,6,6,12,6,12,6,6,6,12,6,6,6,12,6,12,6,12,6,6,6,6,6,12,6,6,6,6,6,12,6,6,118,24,6,12,6,6,6,12,6,6,6,6,6,12,6,12,6,6,6,12,6,6,6,12,6,12,6,12,6,6,6,6,6,12,6,6,6,6,6,12,6,6,118
"Sony Region Free Code 3",84,24,6,12,6,6,6,12,6,6,6,12,6,6,6,12,6,6,6,12,6,6,6,12,6,12,6,12,6,6,6,6,6,12,6,6,6,6,6,12,6,6,118,24,6,12,6,6,6,12,6,6,6,12,6,6,6,12,6,6,6,12,6,6,6,12,6,12,6,12,6,6,6,6,6,12,6,6,6,6,6,12,6,6,118
"Sony Region Free Code 4",84,24,6,12,6,12,6,12,6,12,6,12,6,6,6,12,6,6,6,12,6,6,6,12,6,12,6,12,6,6,6,6,6,12,6,6,6,6,6,12,6,6,117,24,6,12,6,12,6,12,6,12,6,12,6,6,6,12,6,6,6,12,6,6,6,12,6,12,6,12,6,6,6,6,6,12,6,6,6,6,6,12,6,6,117
"Sony Region Free Code 5",84,24,6,12,6,6,6,12,6,6,6,12,6,6,6,6,6,6,6,12,6,6,6,12,6,12,6,12,6,6,6,6,6,12,6,6,6,6,6,12,6,6,118,24,6,12,6,6,6,12,6,6,6,12,6,6,6,6,6,6,6,12,6,6,6,12,6,12,6,12,6,6,6,6,6,12,6,6,6,6,6,12,6,6,118
4. Boot up your PC from the floppy disk and run winsamp.exe.
If your IRDA port doesn't appear as COM2 you may override this by using an appropriate command line switch. For example, use COM1 by running 'winsamp C1'.
5. Press the 'r' key to load up the codes into winsamp.
6. Make sure your DVD player is in standby mode and your IRDA port is within range.
7. Run the IR codes from 1 to 5 by pressing Enter on each corresponding button.
8. Your DVD player should start up and display the text "SUCCESS".
9. Repeat step 7. Your player should return to standby mode.
Your player is now multi-region.
1. not all players display 'SUCCESS', some will display 'TIMER OK'
2. it's not essential to extract the winsamp package to a floppy, or to boot the computer in DOS mode if you are using windows 98 or lower. running the program in a DOS shell works fine. I think it may be necessary if using a computer running XP.
3. after unlocking my machine, I was able to successfully play a region 1 DVD. However, because it used the NTSC colour format, pictures appeared black and white on my PAL TV. This was because i was using a composite video connection. Changing the connection to RGB restored full colour (and sharper picture generally).
I hope the above is helpful.
Thanks to all the people that Magaman thanked and thanks to him - two and a bit years later!!Thanks to all of you guys in this forum
Used Kameleon 3 in 1 (One for All Kameleon URC-8203)
to hack the SONY DVP-NS52P for Multiregion playback.
First prepare the remote:
1. select dvd device on remote (dvd icon)
2. hold magic button (for 3 sec.) until rabbit comes out of the hat
3. enter device code 0533
Now program buttons 1-5 with the following codes:
1 - 00189
2 - 00255
3 - 00095
4 - 00221
5 - 00079
To program keys with this remote do the following:
1. hold magic button device key blinks twice
2. press 994
3. press magic button
4. enter 5 digit code from above (ex: 00189)
5. press button (1..5) where to program it
Repeat steps 1 to 5 for all (five) keys.
After this just apply the hack:
1. remove disk, put player on standby
2. press 1,2,3,4,5 - SUCCESS is displayed
3. press 1,2,3,4,5 (again) - SUCCESS is displayed again! Put player on standby
Thats it! It works! Now it plays R1, R2 and R3 disks (I dont own other regions disks).