On Mon, Jul 12, 2004 at 05:30:47AM -0700, vrs wrote:
> I could help relieve someone of the burden of excess PDP-8 cartridges, too
> :-)!
I think a lot of us could... I myself have a number (a few dozen, some
with versions of RT-11, some with random contents) of 12-sector packs and
one 16-sector F pack (never been able to read it, and I've had it for 20
years!) and one 16-sector J pack.
One thing that's come up here a couple of times is what it would take to
"convert" either a 12-sector hub to a 16-sector hub, or to modify a drive
to read 12 sector marks, but to pass along 16 sector marks to the electronics.
Since 12 and 16 share a common denominator of 4, you would be able to keep
4 sector slits intact, block up 8, and make 12 new ones... not impossible,
as long as you could keep any aluminum dust off the platter.
If anyone has any *crashed* 16-sector packs, it might be worth an experiment
to unclamp the hub and put it on a former 12-sector platter, and reformat.
I don't know if that's even possible, but it's an idea.
> The question lurking in my mind, though, is are the 'F' cartridges different
> from the 'J' cartridges? (I have a couple of RK05F drives that I'd like to
> convert to PDP-8 use.)
Inherently, no, but the F packs have been tested and qualified for twice as
many tracks (the differences between an RK05F drive and an RK05J drive are
a few jumper settings, different heads, and different mounting mechanisms -
the J has the full door and pack guide rails; the F has a blank front-panel
and uses a plastic wedge and springs screwed to the pack since it's fixed).
Much like taking an ST-225 and formatting it on an RLL controller as if it
were an ST-238, it's theoretically possible to take a J pack and mount it
in an F drive, but there's a potential for data loss.
-ethan
--
Ethan Dicks, A-130-S Current South Pole Weather at 12-Jul-2004 24:00 Z
South Pole Station
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Ethan.Dicks_at_amanda.spole.gov http://penguincentral.com/penguincentral.html
Received on Mon Jul 12 2004 - 19:11:37 BST