2 Oct
2022
2 Oct
'22
2:58 a.m.
How "stable" is bubble memory, over decades?
There is a Sharp PC-5000 that may be available, I believe from 1983-1985
era, which is said to have bubble memory. But the owner can't find a power
cable, to verify if anything still works.
I have older systems with ICs that are still working OK, but I was
wondering thoughts on any risk associated with bubble memory? (likelihood
of not working at all, or being damaged in long distance shipping)
Actually another thought, can any "normal" ICs be used to
replace/substitute the bubble memory?
Regards,
Steve
2 Oct
2 Oct
4:38 a.m.
Hi Steve,
the Sharp PC-5000 bubble memory is very reliable. It`s working flawless
on two machines I have.
Bubble memory was used as well in some significant older machines, like
the Texas instruments Silent Terminals (around 77 I guess). And last
time I turned on the terminal, it worked perfectly still showing text in
memory, entered decades ago. So no worry.
Thomas
Am 02.10.2022 um 10:58 schrieb Steve Lewis via cctalk:
How "stable" is bubble memory, over
decades?
There is a Sharp PC-5000 that may be available, I believe from 1983-1985
era, which is said to have bubble memory. But the owner can't find a power
cable, to verify if anything still works.
I have older systems with ICs that are still working OK, but I was
wondering thoughts on any risk associated with bubble memory? (likelihood
of not working at all, or being damaged in long distance shipping)
Actually another thought, can any "normal" ICs be used to
replace/substitute the bubble memory?
Regards,
Steve
9:02 a.m.
How "stable" is bubble memory, over
decades?
There is a Sharp PC-5000 that may be available, I believe from 1983-1985
era, which is said to have bubble memory. But the owner can't find a power
cable, to verify if anything still works.
I have older systems with ICs that are still working OK, but I was
wondering thoughts on any risk associated with bubble memory? (likelihood
of not working at all, or being damaged in long distance shipping)
Actually another thought, can any "normal" ICs be used to
replace/substitute the bubble memory?
Bubble memory uses magnetic domains, so to a first approximation it's as
"stable" as any other magnetic storage system. These domains tend to be
relatively large by modern standards. The modules are invariably magnetically
shielded in heavy coverings, and are shockproof. If it works it all, it
probably works fine.
I have a Texas Instruments Silent 700 Model 763 and so far no problems with
storing and retrieving data on its bubble memory cards, even though this unit
is well over 40 years old (here it is with my KIM-1 as a punch tape storage system:
http://oldvcr.blogspot.com/2022/09/what-kim-1-really-needs-is-bubble.html
).
There are no modern drop-in equivalents for bubble memory modules specifically.
Bubble memory is inherently serial and requires additional drive circuitry.
However, that doesn't mean someone couldn't make a unit that emulates the
entire system and looks like a bubble memory storage device, naturally, just
like any other disk emulator.
--
------------------------------------ personal: http://www.cameronkaiser.com/ --
Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckaiser(a)floodgap.com
-- Do you think I could buy back my introduction to you? -- Groucho Marx ------
2:51 p.m.
Second that. I've got a PC-5000 as well (wanna buy it?) and have never had
any issues with the bubble paks.
I suppose it's the computer as well but I was surprised by how relatively
slow they are, considering that they're 'solid state'.
An interesting project, replacing them with SD cards or similar; way beyond
my skills though.
I assume the manual is out there somewhere?
m
On Sun, Oct 2, 2022 at 7:39 AM osi.superboard via cctalk <
cctalk(a)classiccmp.org> wrote:
Hi Steve,
the Sharp PC-5000 bubble memory is very reliable. It`s working flawless
on two machines I have.
Bubble memory was used as well in some significant older machines, like
the Texas instruments Silent Terminals (around 77 I guess). And last
time I turned on the terminal, it worked perfectly still showing text in
memory, entered decades ago. So no worry.
Thomas
Am 02.10.2022 um 10:58 schrieb Steve Lewis via cctalk:
How "stable" is bubble memory, over
decades?
There is a Sharp PC-5000 that may be available, I believe from 1983-1985
era, which is said to have bubble memory. But the owner can't find a
power
cable, to verify if anything still works.
I have older systems with ICs that are still working OK, but I was
wondering thoughts on any risk associated with bubble memory?
(likelihood
of not working at all, or being damaged in long
distance shipping)
Actually another thought, can any "normal" ICs be used to
replace/substitute the bubble memory?
Regards,
Steve
3 p.m.
I suppose it's the computer as well but I was
surprised by how relatively
slow they are, considering that they're 'solid state'.
It's largely the fact that bubble memory is inherently serial. You have to
cycle through all the bits in a line until you get to the right location.
--
------------------------------------ personal: http://www.cameronkaiser.com/ --
Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckaiser(a)floodgap.com
-- BOND THEME NOW PLAYING: "The Living Daylights" -----------------------------
579
days inactive
579
days old
4 comments
4 participants
participants (4)
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Cameron Kaiser -
Mike Stein -
osi.superboard -
Steve Lewis