Mr. Man-wai Chang wrote:

How could a device tell their differences? By looking for a partition
table?

I have a Panasonic TV that can record programs on USB hard disks only. I
am thinking to deceive it by inserting a USB flash drive....


It's possible the information is part of the USB Class
and is in the configuration table of the USB chip.

See the section "Removable or what?" here, where it
mentions DRIVE_REMOVABLE and DRIVE_FIXED. It sounds
like the Panasonic is looking for "DRIVE_FIXED".

http://www.uwe-sieber.de/usbstick_e.html

Looking at this thread, it's suggesting the drive itself has
an "RMB" bit. The hack in this case, involves preventing
the OS from seeing the RMB bit. But you don't have
access to the OS on the Panasonic.

http://hardforum.com/showthread.php?t=1655684

You could try an SSD inside a USB SATA enclosure, as
a means to make it look like a fixed disc. And
then you'd be recording on flash chips, without
the same issues as would exist with a hard drive.

Paul