Good Ol' Twinax (used to be Dedicated console)

Once upon a time (S/36 epoch) We had a 800 meters long underground Twinax
line
carrying three 5251 terminals and a 5256 printer (daisy chained) .

On one occasion when it stopped working (due to rain?) We had an IBM
technician
connecting some sort of electronic device to the S/36 side of that Twinax
line and saying
"There is a short cut / disconnection 5 hundred meters down the line" we
went there and found a faulty Twinax nipple connection. (luckily it was in
a cables pit)

Those were the days...

Gad

And, a Twinax cable is STRONG, you could tow your car using Twinax

On 5/21/2021 1:20 PM, James H. H. Lampert wrote:

> ...IBM has thrown out a connectivity technology as bulletproof
> as Twinax.

OK Maybe you couldn't kill it with bullets, but I've seen twinax in
walls pierced with screws to mount drywall. I've seen customers slice
out walls and take the twinax with it. I've seen 16" Steel I-beams cut
to allow large fork lifts to pass and oddly the twinax laying in that
was sliced as well.

Further I've seen twinax simply pulled right out of the connector. I've
seen two wire extension cords used thus removing the ground and wiping
out an entire string of terminals. I've seen a pile of twinax thrown up
on top of a conference room ceiling ended up laying on the fluorescent
light. Every time the light was turned on or off that string of
terminals went down!

We kinda remember the good parts but man when Twinax didn't work there
were a thousand things to check!

- DrF


--
IBM Champion for Power Systems