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* Re: [TUHS] Spider
@ 2020-01-24  1:28 Paul Ruizendaal
  2020-01-24  2:37 ` Jon Steinhart
  0 siblings, 1 reply; 6+ messages in thread
From: Paul Ruizendaal @ 2020-01-24  1:28 UTC (permalink / raw)
  To: TUHS main list

> Ugh. Memory lane has a lot of potholes. This was a really long time ago. 

Many thanks for that post - really interesting!

I had to look up "Pierce Network", and found it described in the Bell Journal:
https://ia801903.us.archive.org/31/items/bstj51-6-1133/bstj51-6-1133_text.pdf

In my reading the Spider network is a type of Pierce network.

However, the network that you remember is indeed most likely different from Spider:
- it was coax based, whereas the Spider line was a twisted pair
- there was more than one, whereas Spider only ever had one (operational) loop

Condon and Weller are acknowledged in the report about Spider as having done many of its hardware details. The report discusses learnings from the project and having to tune repeaters is not among them (but another operational issue with its 'line access modules’ is discussed).

All in all, maybe these coax loops were pre-cursors to the Spider network, without a switch on the loop (“C” nodes in the Pierce paper). It makes sense to first try out the electrical and line data protocol before starting work on higher level functions.

I have no idea what a GLANCE G is...





^ permalink raw reply	[flat|nested] 6+ messages in thread
* Re: [TUHS] Spider
@ 2020-01-23  8:38 Paul Ruizendaal
  2020-01-23 17:40 ` Jon Steinhart
  0 siblings, 1 reply; 6+ messages in thread
From: Paul Ruizendaal @ 2020-01-23  8:38 UTC (permalink / raw)
  To: TUHS main list


> I have vague memories here that maybe Heinz can help with if his are any better.
> I believe that Sandy played a part in "the loop" or "the ring" or whatever it
> was called that we had connecting our Honeywell 516 to peripherals.  I do
> remember the 74S00 repeaters because of the amount of time that Dave Weller
> spent tuning them when the error rate got high.  Also, being a loop, Joe
> Condon used to pull his connectors out of the wall whenever people weren't
> showing up to a meeting on time.  I don't know whether our network was a
> forerunner to the spider network.

It most likely was Spider - it became operational in 1972. The vist report that I linked to earlier also says:

"The current system contains just one loop with the switching computer (TEMPO I),
four PDP-11/45 computers, two Honeywell 516 computers, two DDP 224 computers,
and one each of Honeywell 6070, PDP-8 and PDP-11/20. In fact many of these are
connected in turn to other items of digital equipment.”

It would be interesting to know more about the H516’s and Spider, any other recollections?




^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2020-01-26  1:01 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-01-24  1:28 [TUHS] Spider Paul Ruizendaal
2020-01-24  2:37 ` Jon Steinhart
2020-01-24  3:03   ` Gregg Levine
2020-01-26  1:01   ` Heinz Lycklama
  -- strict thread matches above, loose matches on Subject: below --
2020-01-23  8:38 Paul Ruizendaal
2020-01-23 17:40 ` Jon Steinhart

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