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jls1504
03-20-2012, 09:14 AM
Hi all,
i just bought a 37PFL7666H/12 (France) and i am satisfied with this TV set.
I complemented it with a home made mediacenter, that i use to record TV programs. I want to use the usb recording feature of the TV to enable timeshift. To do so, i connected a SANDISK 32 Gbit USB Key (model SDCZ52-032G-B35), the description of which can be found here :

http://www.sandisk.fr/products/usb-flash-drives/cruzer-switch-usb-flash-drive

The TV formatted the key, then made the write performance test, and the conclusion was "this drive is not fast enough to
enable timeshift" !!

Quite a strange result for a flash drive ! According to the user's manual, the requirement is a disk with a minimum write speed of 30 Mbit/s. This usb key achieved more than 100 Mbit/s when i tested it on my computer.

Did anyone have a similar problem ? Can anyone suggest a alternate usb key that proved to work correctly in this context ?
Thank you
JLS

Perpetual Beta
03-20-2012, 02:35 PM
Hi all,
[..] 37PFL7666H/12 (France) [..]
[..]32 Gbit USB Key (model SDCZ52-032G-B35) [..]

The TV formatted the key, then made the write performance test, and the conclusion was "this drive is not fast enough to
enable timeshift" !!

[..] According to the user's manual, the requirement is a disk with a minimum write speed of 30 Mbit/s. This usb key achieved more than 100 Mbit/s when i tested it on my computer.

Did anyone have a similar problem ? [..]

Enable "Show threads from the... Last Year" in "Forum: TV: USB-recording" and you will see (http://www.supportforum.philips.com/en/showthread.php?2924-Only-HDD-can-be-used&daysprune=365).

Philips will have to decide whether the minimum recording speed is
30MBps (30 MByte/second) as written in the "EN User Manual" 37pfl7666h_12_dfu_eng.pdf page 25
or
30 Mb/s (30 Mbit/second) as written in the "FR Mode d'emploi", 37pfl7666h_12_dfu_fra.pdf page 32).
Unfortunately the technical specification of a minimal write speed makes little sense without the specification of a maximal write latency, especially for flash and harddisk storage.

My guess, as told here in the forum: Better take 30 MByte/second minimal write speed. Philips did implement the USB recording feature with technical limits above the abilities (sustainable write speed, write latency) of most USB 2.0 flash drives sold e.g. at amazon. On top of it all the TV's USB port is delivering 0,5A max. which is not enough for several 2,5" external hard disks and not enough for the most USB 3.0 flash drives. And several "32 GB Flash drives" have a formatted capacity below 32 GB.

I've tested a 64 GB USB 3.0 flash drive (Sharkoon Flexi-Drive Accelerate Duo) here (42PFL7456K/02 FW 000.014.093). With USB 3.0 hub to get enough power (otherwise errors during writing / formatting operations). I can get a PC DVB-S2 TV card for that money so the test was briefly.