[GreenKeys] available

[Chris Elmquist]

On Saturday (08/20/2011 at 09:05PM -0400), Christian Gauger-Cosgrove wrote:
> 3.5" is probably useless. 5.25" ... has gotten very, very rare. (Now,
> if you have 8" I would be interested...)

Well, not exactly.  I have built an emulation of 5.25" hard-sector
floppies used in the Heathkit H8 and H89 computers (which were 10-hole,
hard-sectored floppies) that uses a 3.5", 720K drive and media.   This
scheme will work for other old systems that used 10-hole, hard-sectored
media such as the NorthStar Horizon as well.   So, if you have 720K 3.5"
media, that is of use to some of us.

If they are 1.44MB, 3.5" media, then they can be used as well although
somewhat less reliably.  You can cover the density select hole in the
upper left with a piece of black tape and then the 3.5" drive will treat
them as 720K media (ultimately, this changes the bit rate recorded on
the media to 250Kbps which is what these old systems use).

We have also developed a hand-held punch which can turn 5.25"
soft-sectored floppies into 10- and 16-hole hard-sectored floppies for
many different legacy systems.  This has made 5.25" media less rare for
our purposes since you can still buy 5.25" soft-sector media new and
then we just punch them to get whatever hard-sector supply we need.

So, I would say the most useful of all of these would be 3.5" if they
are 720K type--  those will have just one hole or slot at the top
of the media...  and that is the hole with the write-protect slider.
There will be no other hole directly across from that one.  A 1.44MB
will have another hole or slot across from the write-protect without
any slider in it.

Chris N0JCF

> On 20 August 2011 20:36,  <telegrapher at q.com> wrote:
> > Does anyone need or still use 3 1/2 inch disks?  i've probably got 8 or more boxes of them, at least 3 unopened along with a variety of the 5 1/4 inch ones as well.  Otherwise i can use them for target practice with my new Henry rifle.  Wonder what they will sound like when they get hit?  Aim for the center and hope you hit the target soldier!
> >
> > Larry
> > W0OGH
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-- 
Chris Elmquist