On Tue, Aug 11, 2020 at 11:41 AM John Wettroth via TriEmbed
<[email protected]> wrote:
>
> Not so much on the technology side and not quite as old but I found some ISA 
> card hacking stuff in a recent cleaning.  Two are extenders- to get the card 
> out of the box to probe on, one 8 bit (XT) and one 16 bit (AT).  I also have 
> an ISA-8 card with a solderless breadboard on it.  I will included Ed Nisley 
> book on hacking ISA computers (if I can find it).  All to a good home if you 
> have a use for it.  I also have some ISA card eprom programmers of similar 
> vintage and other miscellany.
>
      Somewhat related question: can anyone recommend me an old dual
or quad port ethernet card that is 5V PCI 32bit slot- and
Linux-friendly? I want to compare something with my PCI-e cards but
found while my motherboard has PCI-e v3 slots, it does not have 3.3V
PCI slots, which seems to be all of the multiport ethernet cards I can
find. It does not need to be gigabit.

> John Wettroth
> 919 349-9875
>
> ________________________________
> From: TriEmbed [mailto:[email protected]] On Behalf Of Rodney 
> Radford via TriEmbed
> Sent: Monday, August 10, 2020 9:40 AM
> To: Robert Mackie
> Cc: TriEmbed Discussion
> Subject: Re: [TriEmbed] Old computers
>
> This is the first time I have seen another one - thanx for the photo and the 
> back story. If you find the patent number, I would be interested in seeing it.
>
> After watching someone interface an Arduino to core memory at the virtual 
> computer festival, I wondered how difficult it would be to interface an 
> Arduino to this delay line. Mine has 12v stamped on the board, so that gives 
> me some hint as to voltages, and the electronics on the board is simple, so 
> should be possible to sketch out a schematic of the read and write circuits.
>
>
> On Mon, Aug 10, 2020 at 3:10 AM Robert Mackie <[email protected]> wrote:
>>
>> Rodney,
>>
>> Oddly enough, I see the photos attached.
>>
>> re:  a mechanical delay line
>>
>> My dad worked for IBM way back in the day, as an electrical engineer.
>>
>> He left me copies of a few of the patents on which he was listed as an 
>> inventor. One of them is exactly such a device, used at the edge of 
>> telephone switching networks (I think - edge of some network anyway) to hold 
>> state. Much cheaper than core memory for the time, and could hold 2048 bits, 
>> with a latency of something like 50ms. Somewhere I have the paperwork for 
>> the patent application. Now I'm curious if it was a refinement or the first 
>> of its type. Never thought about it before.
>>
>> But this is one where he had kept a physical example, one they had to cut 
>> open during testing. I knew exactly where it was so I just snapped a photo 
>> with my phone:
>>
>> http://mackies.org/mechanical_delay_line_dynamic_memory_ibm.jpg
>>
>> Figured it would be interesting to see and compare.
>>
>> Rob.
>>
>> On Sun, Aug 9, 2020 at 6:14 PM Rodney Radford via TriEmbed 
>> <[email protected]> wrote:
>>>
>>> Nevermind, the photos 440k were deemed too large to be sent by the TriEmbed 
>>> server.
>>>
>>> Sorry you will not be able to see them.
>>>
>>>
>>> On Sun, Aug 9, 2020 at 5:38 PM Rodney Radford <[email protected]> wrote:
>>>>
>>>> I forgot to include the photos...
>>>>
>>>>
>>>> On Sun, Aug 9, 2020 at 5:37 PM Rodney Radford <[email protected]> wrote:
>>>>>
>>>>> One of the passions I have put time in the last few months are collecting 
>>>>> and learning about old vintage computers.
>>>>>
>>>>> I currently have:
>>>>> * IMSAI S-100 system
>>>>> * Sol-20 S-100 system
>>>>> * TRS-80 Model 1 and 4p
>>>>> * Two Apple IIe systems
>>>>> * Kaypro 10 luggable system
>>>>> * TI 99/4
>>>>>
>>>>> I used to have a much larger collection including
>>>>> * Burroughs L5000 (google about that beast)
>>>>> * TRS-80 Model 2, 3 and 4
>>>>> * Zerox CP/M system (I think I still have it, but can't find it)
>>>>> * Pet Commodore 2001 (loaned to a 'friend' - never got it back)
>>>>> * several Apollo systems
>>>>>
>>>>> While I wish I could have kept all the old systems, it just was not 
>>>>> possible due to storage space constraints.
>>>>>
>>>>> Back in highschool, a teacher gave me her old 4-function Singer (yes, the 
>>>>> sewing machine) calculator. I, of course, took it apart... ;-)
>>>>>
>>>>> I did keep two parts from the calculator - the keyboard (mechanica 
>>>>> marvel) and the storage device (a mechanical delay line).
>>>>>
>>>>> When I first looked inside, I saw the aluminum box with the words read 
>>>>> amp and write amp on it, and I *knew* I had found core memory. Then I 
>>>>> opened it and was completely surprised with what I found. It is a 
>>>>> magnetostrictive delay line memory device - memory was stored by twisting 
>>>>> the wire at one end, and the twist would propogate through the long coil 
>>>>> and out at the other end. By varying the direction of the twist, data 
>>>>> could be stored temporarily, and it was then sent back in again for 
>>>>> storage again.
>>>>>
>>>>> The other item I kept from the calculator was the keyboard. On each 
>>>>> keypress, the key was decoded with gears and levers that move magnets 
>>>>> over reed relays - as that was more economical than a simple electronic 
>>>>> keyboard decoder.
>>>>>
>>>>>
>>>>> Here is a link to information about the calculator (and some info on the 
>>>>> delay line):
>>>>>
>>>>>
>>>>> https://www.oldcalculatormuseum.com/friden1160.html
>>>>>
>>>>>
>>>>> Photos included of the delay line and keyboard. If we were meeting in 
>>>>> person Monday, I would have brought them out for show and tell.
>>>>>
>>>>> I also really enjoyed the virtual vintage computer festival I mentioned 
>>>>> earlier. Some really good talks on that, and my first of four books I 
>>>>> ordered arrived today - the ENIAC Technical Reference manual, as written 
>>>>> by one of the first female programmers on it.
>>>>>
>>>>>
>>>>> PS: If you have any old systems that need a home let me know. I really 
>>>>> should have grabbed the TRS-80 Model 100 that I brought last year that 
>>>>> was given to the club, but I let someone else take it (any idea who 
>>>>> grabbed it?)
>>>>>
>>>>>
>>>>> Anyway, back to current time where I need to finish up an IoT device for 
>>>>> work... ;-)
>>>>>
>>>>>
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