On 3 Jun 2009 at 21:48, Curtis H. Wilbar Jr. wrote:
DC600A = 9 tracks 60MB (600 ft tape), 550 Oersted
DC6150 = 18 tracks, 150MB (600 ft tape), 550 Oersted
I'd guess you can do 150MB on a DC600A as long as it is bulk erased
first (I'd imagine the individual tracks are narrower on a QIC-150
formatted tape vis a QIC-24 format (60M) tape (much like 1.2M 5.25"
floppy tracks are narrower than on the 360K drive (which led to all
sorts of 'fun' writing 360K disks on a 1.2M drive!)))
That's odd--all of my 6150s are 620 ft. 6250s are 550 Oersted, but
1020 ft.
What QIC-02 drives taking DC-600-sized carts require preformatted
tape?
I've got a Cipher 525 that takes DC600A carts, but it's a floppytape
interface and probably requires preformatting. I've also got an
Iomat requires a preformatted tape as the EOT and BOT markers are
encoded (instead of holes in the tape).
But all of my QIC02/QIC36/SCSI tape drives don't care what's on the
tape beforehand. 9 tracks, 11 tracks, 18 tracks--it's all the same.
On a related bit, I've gotten tapes in that were clearly written on
the same system, but 310 Oe (DC300XL) tapes mixed with with 550 Oe
(DC600A) tapes. Didn't seem to matter as far as readability 15 years
down the road.
--Chuck