Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Jon Elson via cctalk
On 06/28/2018 12:22 PM, Liam Proven via cctalk wrote: What amazed me is that none of the NICs blew, none of the machines failed or died. Once the cabling was sorted, it was OK. Who knew that BNC Ethernet ports could handle 100V or more flowing through them and mostly work? They are

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Noel Chiappa via cctalk
> From: Eric Smith > If you _must_ run a long -232 cable 'Don't!' That's what -422 is for. :-) Noel

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Chuck Guzis via cctalk
On 06/28/2018 01:42 PM, Eric Smith wrote: > On Thu, Jun 28, 2018 at 2:20 PM, Chuck Guzis via cctalk > mailto:cctalk@classiccmp.org>> wrote: > > So, on a TIA/EIA/RS-232C DB-25 connector, what's the official position > on pin 1?  The standards calls it PGND = Protective ground and most >

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Peter Coghlan via cctalk
On 2018-06-28 at 13:20:25 -07:00, Chuck Guzis via cctalk wrote: > > So, on a TIA/EIA/RS-232C DB-25 connector, what's the official position > on pin 1? The standards calls it PGND = Protective ground and most > reference seem to indicate that this is chassis/earth ground at both > ends of a

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Liam Proven via cctalk
On Thu, 28 Jun 2018 at 21:14, Bill Gunshannon via cctalk wrote: > > I realize that, just pointing out that the threat was already well known > by the 1980's. Ah, ISWYM now. Sorry. Yes, in that case, you're absolutely right. -- Liam Proven - Profile: https://about.me/liamproven Email:

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Eric Smith via cctalk
On Thu, Jun 28, 2018 at 2:20 PM, Chuck Guzis via cctalk < cctalk@classiccmp.org> wrote: > So, on a TIA/EIA/RS-232C DB-25 connector, what's the official position > on pin 1? The standards calls it PGND = Protective ground and most > reference seem to indicate that this is chassis/earth ground at

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Chuck Guzis via cctalk
On 06/28/2018 09:45 AM, Eric Smith via cctalk wrote: > Of course, this isn't specific to Ethernet. It can happen with e.g. > TIA/EIA-232 (formerly RS-232) as well, and in fact that is even more common > in practice, because Ethernet is transformer-isolated at each station, but > TIA/EIA-232 is

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Bill Gunshannon via cctalk
On 06/28/2018 02:37 PM, Liam Proven wrote: > On Thu, 28 Jun 2018 at 20:13, Bill Gunshannon via cctalk > wrote: > >> The US Electrical Code has not allowed any kind of signal wire in >> the same conduit with any kind of power wiring for as far back as >> I can remember. > Sounds very sensible,

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Liam Proven via cctalk
On Thu, 28 Jun 2018 at 20:13, Bill Gunshannon via cctalk wrote: > > The US Electrical Code has not allowed any kind of signal wire in > the same conduit with any kind of power wiring for as far back as > I can remember. Sounds very sensible, but the Isle of Man isn't part of the USA, nor even

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Bill Gunshannon via cctalk
On 06/28/2018 01:22 PM, Liam Proven via cctalk wrote: > On Thu, 28 Jun 2018 at 18:45, Eric Smith via cctalk > wrote: >> In case it may not be obvious to some readers, the reason you should NEVER >> ground an Ethernet cable (of any kind) at two points is that the ground >> potential at two

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Liam Proven via cctalk
On Thu, 28 Jun 2018 at 18:45, Eric Smith via cctalk wrote: > > In case it may not be obvious to some readers, the reason you should NEVER > ground an Ethernet cable (of any kind) at two points is that the ground > potential at two different points is unlikely to be the same, so that will > cause

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Eric Smith via cctalk
On Thu, Jun 28, 2018 at 7:18 AM, Paul Koning via cctalk < cctalk@classiccmp.org> wrote: > > On Jun 28, 2018, at 4:52 AM, Peter Coghlan via cctalk < > cctalk@classiccmp.org> wrote: > > On a slightly different point, didn't the thickwire spec call for the > outer > > conductor of the cable to be

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread systems_glitch via cctalk
Thanks for the clarifications, Paul! Indeed, some thinnet devices do have terminators built in. On a fair bit of Allied Telesyn gear, there's a switch for it. Thanks, Jonathan On Thu, Jun 28, 2018 at 9:18 AM, Paul Koning via cctalk < cctalk@classiccmp.org> wrote: > > > > On Jun 28, 2018, at

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Paul Koning via cctalk
> On Jun 28, 2018, at 4:52 AM, Peter Coghlan via cctalk > wrote: > > On 2018-06-27 19:34:38 -07:00, Chuck Guzis via cctalk wrote: >> On 06/27/2018 04:19 PM, Antonio Carlini via cctalk wrote: >> >>> No idea. But on thickwire the taps were all supposed to be made at >>> specifically marked

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread systems_glitch via cctalk
Thinnet is supposed to be grounded at one point, and only one point, as well. Supposedly that's what the chain on some terminators is for. Some hubs have a grounding and termination option built in. I don't know offhand if this was specced in the standard or not. Of course, this often wasn't

Re: IBM junk

2018-06-28 Thread Sam O'nella via cctalk
Oops. *Roswell not Atlanta. Sent from my Apple /c > On Jun 28, 2018, at 7:15 AM, Sam O'nella wrote: > > It's Lonnie in Atlanta. Spoken to him a few times in email and he/they are a > serious investor in computer history. They also helped vintage computer > festival southeast get a

Re: IBM junk

2018-06-28 Thread Donald via cctalk
I don’t recall if I had any 3880 documents. I will ask how they would like to handle this type of request. There are many duplicates and they will need time to catalog the documents.

Re: IBM junk

2018-06-28 Thread Sam O'nella via cctalk
It's Lonnie in Atlanta. Spoken to him a few times in email and he/they are a serious investor in computer history. They also helped vintage computer festival southeast get a location originally. It's a good home for that gear. Sent from my Apple /c > On Jun 28, 2018, at 2:55 AM,

Re: IBM junk

2018-06-28 Thread Donald via cctalk
I don’t think so.

Re: Thicknet/10base5 Test Segment: The Cable is In!

2018-06-28 Thread Peter Coghlan via cctalk
On 2018-06-27 19:34:38 -07:00, Chuck Guzis via cctalk wrote: > On 06/27/2018 04:19 PM, Antonio Carlini via cctalk wrote: > > > No idea. But on thickwire the taps were all supposed to be made at > > specifically marked positions (for the reason given earlier). > > Perhaps someone (incorrectly)

Re: IBM junk

2018-06-28 Thread Christian Corti via cctalk
On Wed, 27 Jun 2018, Donald wrote: The whole collection went to Computer Museum of America in Roswell, GA https://computermuseumofamerica.org/ Is that the museum that formerly was in San Diego? Christian