Panasonic PD LM-R650J

[Philip Pemberton]

Zane H. Healy wrote:
> I am looking for info on "Panasonic PD LM-R650J" optical media, and on what
> kind of drives can read it.  I gather it is a 650MB Cartridge of some sort.

Does it have a little "PD" logo on the metal shutter? If so, it's probably one 
of the Panasonic "PD" (phase-change digital) discs.

I remember reading about these in the mid-1990s, just before CD-RWs became 
widespread. They never really caught on (I certainly don't recall anyone 
selling the drives or the discs) and AIUI died off some time in the early '00s.

There's a (small) amount about them on Wikipedia: 
<http://en.wikipedia.org/wiki/Phase-change_Dual>
Basically, they store 650MB of data, and work similarly to a CD-RW (i.e. 
phase-change recording). You can read, write and erase them a few thousand 
times, but they're not readable in standard CD drives.

Apparently a first-generation Panasonic DVD-RAM drive (that'll be the ones 
that take the big cartridges) can read them, but I suspect finding one of 
those in working condition might be difficult. Finding a working PD drive 
would probably be even more difficult... optical drives don't usually stay 
working for long IME.

-- 
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/