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Re: Rarest Card

On Mon, 19 Oct 2009, Michael J. Mahon wrote:


rhohler wrote:

The NuMustang discussion got me thinking.  What is the rarest Apple II
card today?  Of course, prototype cards are limited and rare but what
production card.  I would bet on the Transwarp II card or something.


I have some 128K bubble memory cards that emulate a Disk ][ with
somewhat less capacity.  They were made by Helix Labs, and were
intended to provide non-volatile storage for Apple II's used in
harsh industrial environments.

I don't have easy access to serial numbers, but I'm guessing that
not too many were made and even fewer survive.

Some of you may remember that magnetic bubble memory (in which small
circular magnetic domains ("bubbles") circulate on a thin garnet
substrate under the influence of external magnetic fields) were
expected to eventually replace magnetic disks in the late 1970s!


They were still seen that way in the early to mid-eighties. Basically
"it's just around the corner, soon bubble memory will be cheap and you'll be glad". 

I'm not sure if there were problems making it cheap, or other things came
along that were just so much better that bubble memory was dropped in favor of silicon memory.
At the time, the density was quite high, but now what was available a quarter century ago is pretty minor.
I do find it amusing that cheap high density memory really just snuck up on us, for a long time it never seemed to keep up with demand, until in the past decade or so you could get memory so cheap that you could throw it away on things like MP3s. 

   Michael