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
Does anyone have a Philips P2000C CP/M luggable with the carrying strap?
I will be restoring such a machine in the near-ish future and mine is
lacking the strap. Clear photos of the end fittings that slot into the
machine, the dimensions of them, etc would be a great help in making
something up.
-tony
Hi,
I recently acquired a Solid State Music SB-1 from which all the chips had
been removed. I've reinstalled all of the chips (I located an SSM2000) and
I've been trying to figure out why this board crashes my computers. The
conclusion that I've come to is rather astounding. The board specifies two
74ls85 4 bit binary comparator chips to perform address decoding. The
designers of this board seem to have had incorrect pinouts for it. Every
source that I can find specifies:
B3 1 16 VCC
A<B (in) 2 15 A3
A=B (in) 3 14 B2
A>B (in) 4 13 A2
A>B (out) 5 12 A1
A=B (out) 6 11 B1
A<B (out) 7 10 A0
GND 8 9 B0
The 7485s that I was able to get have this pinout. BUT! The SB-1 is
designed as:
B2 1 16 VCC
A2 2 15 A3
A=B (out) 3 14 B3
A>B (in) 4 13 A>B (out)
A<B (in) 5 12 A<B (out)
A=B (in) 6 11 B0
A1 7 10 A0
GND 8 9 B1
I Ohm'd out the board to verify this and it matches the schematic here:
https://wiki.theretrowagon.com/wiki/Solid_State_Music_SB1
What the heck??? Did the pinout of the 7485 just arbitrarily change at some
point? Was this some competition between manufacturers? Is there any way
to get the "right" 7485?
Thanks,
Bill
--
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www.avast.com
A bit off topic but I'm curious if anyone has any technical information on
Animatics motion controllers. Animatics was based in (Santa Clara) in
the 1990s. They were bought by Moog sometime around 2000 and all the old
info was thrown out.
A support engineer working for Moog (who had worked for Animatics before
the buyout) provided a bunch of DOS utilities and info on the RS232
programming that he found on a backup, but this is all the info that exists.
Schematics for the hardware (CPU is a Phillips SCC68070 with a MC68881 math
coprocessor), firmware code and any other technical info would be great.
Wayback machine link:
http://web.archive.org/web/19990218104405/http://www.animatics.com/5000list…
eBay link to an actual controller: https://www.ebay.com/itm/124030784795
I have just stumbled across this nice "Timeline of Computer History" from
the CHM:
https://www.computerhistory.org/timeline/computers/
I have not seen this before and thought it may be of interest to this list.
Tom
Is it just me? I have recently sent an email to this guy about two
different topics. There was no response in either case. What is going on?
Or am I missing something?
Many thanks,
peter vp
I know this is sacrilege but I am looking for the front panel of a *Data
General Nova *and/or *a DEC PDP 8/11/12/15*.
Why? I collect artefacts from the days of the minicomputer and earlier and
I want them for my collection/display. They should be not too damaged and
of course do not need to be functional. I would be willing to pay
postage/freight.
Any offers? Any offers?
Peter
PS Please don't shout at me!
All the discussion around 8" disks reminded me about a question I've not
been able to find an answer to.
I've got a Qumetrak 842 drive that I use for imaging 8" disks with either
ImageDisk or AppleSauce. When I first tried it out with AS, the listed
RPM was > 7K. It turns out that the disk I was working with was a NOS
Dysan that had both the single and double-sided index windows punched in
the jacket. The 842 has both of those index sensors, so both were being
triggered one after the other. The solution was to cover one of the index
windows on the disk.
The question I have is how did a contemporary system deal with the
combination of a disk with both index windows and a drive with both index
sensors?
tnx!
g.
--
Proud owner of F-15C 80-0007
http://www.f15sim.com - The only one of its kind.
http://www.diy-cockpits.org/coll - Go Collimated or Go Home.
Some people collect things for a hobby. Geeks collect hobbies.
ScarletDME - The red hot Data Management Environment
A Multi-Value database for the masses, not the classes.
http://scarlet.deltasoft.com - Get it _today_!
Hi All:
I’m pleased to report that my 11/45 and 11/34 which were in need of a new home have been taken by another collector here in BC. They will be off to a very good home!
Thanks for reading my post.
Kevin
