AUI to AUI cheaply, how?

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Derrick J. Brashear

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Mar 1, 1994, 11:14:52 PM3/1/94
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Hi,

I have 2 machines here with free AUI ports, and I'd like to connect
*just* these two machines, i.e., there is no need for anything beyond a
connection to these two machines. What I'd like to know is, what is the
absolute cheapest way I can do it? I have a very limited budget, to say
the least....

Here's what I have:
a Sun 3/160, one AUI connected to the rest of the world, a second AUI
board with no network interface connected...
a Sun 3/80, one free AUI port
one AUI to BNC transceiver
two AUI to LattisNet transceivers

Ideas, anyone?

TIA,

-D

steve.

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Mar 2, 1994, 1:57:01 PM3/2/94
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In article <chR1_wC00...@andrew.cmu.edu> Derrick J. Brashear,

db...@andrew.cmu.edu writes:
>Hi,
>
>I have 2 machines here with free AUI ports, and I'd like to connect
>*just* these two machines, i.e., there is no need for anything beyond a
>connection to these two machines. What I'd like to know is, what is the
>absolute cheapest way I can do it? I have a very limited budget, to say
>the least....
>
On pg33 of the newest Black Box catalog there is a device for exactly
what you want to do. It comes with two or four ports for around $235
for the two port and $385 for the four port model.


>Here's what I have:
>a Sun 3/160, one AUI connected to the rest of the world, a second AUI
>board with no network interface connected...
>a Sun 3/80, one free AUI port
>one AUI to BNC transceiver
>two AUI to LattisNet transceivers
>
>Ideas, anyone?
>
>TIA,
>
>-D

-steve.

Syed Zaeem Hosain

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Mar 3, 1994, 6:16:02 PM3/3/94
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In article 51...@newstand.syr.edu, steve. <sema...@syr.edu> writes:
>In article <chR1_wC00...@andrew.cmu.edu> Derrick J. Brashear,
>db...@andrew.cmu.edu writes:
>>Hi,
>>
>>I have 2 machines here with free AUI ports, and I'd like to connect
>>*just* these two machines, i.e., there is no need for anything beyond a
>>connection to these two machines. What I'd like to know is, what is the
>>absolute cheapest way I can do it? I have a very limited budget, to say
>>the least....
>>
>On pg33 of the newest Black Box catalog there is a device for exactly
>what you want to do. It comes with two or four ports for around $235
>for the two port and $385 for the four port model.

*Way* too expensive, IMHO.

Here is what I just did for a friend, with items bought from local
store, (I am including only one transceiver since the list of things
this person already has includes one transceiver):

Allied Telesis MX10S transceiver $39.95 $39.95
BNC 50-ohm terminators (two) $ 2.80 each $ 5.60
BNC T connector (two) $ 2.25 each $ 4.50
BNC RG58 thin-wire cable 25' $ 7.50 $ 7.50
--------
TOTAL $57.55

In CA, toss in a few bucks for sales tax, and you have a solution
for about $62.30 - *much* less than the Black Box solution.

>>Here's what I have:
>>a Sun 3/160, one AUI connected to the rest of the world, a second AUI
>>board with no network interface connected...
>>a Sun 3/80, one free AUI port
>>one AUI to BNC transceiver
>>two AUI to LattisNet transceivers


--
-------------------------------------------------------------------------
| Syed Zaeem Hosain P. O. Box 610097 (408) 441-7021 |
| Z Consulting Group San Jose, CA 95161 s...@zcon.com |
-------------------------------------------------------------------------

Szymon Sokol

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Mar 7, 1994, 5:37:15 AM3/7/94
to chR1_wC00...@andrew.cmu.edu
steve. (sema...@syr.edu) wrote:
: In article <chR1_wC00...@andrew.cmu.edu> Derrick J. Brashear,

$235?!?! I think that Derrick could buy an MX-10 from Allied Telesis (it is
a BNC transceiver; any other BNC transceiver should do) for $50,
two T-connectors and two terminators for <$10, and a piece of thin coax for ...
uhm, $10? This adds up to about $70, not 235, and clearly is the best solution
in this case...
--
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U U M M M M University of Mining and Metallurgy, Computer Center
U U MM MM MM MM ave. Mickiewicza 30, 30-059 Krakow, POLAND
U U M M M M M M M M TEL. +48 12 338100 EXT. 2885 FAX +48 12 338907
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WWW page: http://www.uci.agh.edu.pl/~szymon

Tatjana Heuser

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Mar 7, 1994, 2:35:53 PM3/7/94
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>: In article <chR1_wC00...@andrew.cmu.edu> Derrick J. Brashear,
>: db...@andrew.cmu.edu writes:
>: >Hi,
>: >
>: >I have 2 machines here with free AUI ports, and I'd like to connect
>: >*just* these two machines, i.e., there is no need for anything beyond a
>: >connection to these two machines. What I'd like to know is, what is the
>: >absolute cheapest way I can do it? I have a very limited budget, to say
>: >the least....

I'm wondering if it's possible to connect them *directly* by just crossing
the relevant lines (send-receive, etc).

anyone more knowledgeable to comment?

/tatjana
--
Tatjana Heuser | pie...@cs.tu-berlin.de
Ettaler Str.2 |
D-10777 Berlin | +49 30 / 214 27 58

Syed Zaeem Hosain

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Mar 7, 1994, 11:24:51 PM3/7/94
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In article 2lf04r...@galaxy.uci.agh.edu.pl, szy...@galaxy.uci.agh.edu.pl (Szymon Sokol) writes:
>steve. (sema...@syr.edu) wrote:
>: In article <chR1_wC00...@andrew.cmu.edu> Derrick J. Brashear,
>: db...@andrew.cmu.edu writes:
>: >Hi,
>: >
>: >I have 2 machines here with free AUI ports, and I'd like to connect
>: >*just* these two machines, i.e., there is no need for anything beyond a
>: >connection to these two machines. What I'd like to know is, what is the
>: >absolute cheapest way I can do it? I have a very limited budget, to say
>: >the least....
>: >
>: On pg33 of the newest Black Box catalog there is a device for exactly
>: what you want to do. It comes with two or four ports for around $235
>: for the two port and $385 for the four port model.
>:
>: >Here's what I have:
>: >a Sun 3/160, one AUI connected to the rest of the world, a second AUI
>: >board with no network interface connected...
>: >a Sun 3/80, one free AUI port
>: >one AUI to BNC transceiver
>
>$235?!?! I think that Derrick could buy an MX-10 from Allied Telesis (it is
>a BNC transceiver; any other BNC transceiver should do) for $50,
>two T-connectors and two terminators for <$10, and a piece of thin coax for ...
>uhm, $10? This adds up to about $70, not 235, and clearly is the best solution
>in this case...

Good recommendation! The only difference is that I would recommend the
MX-10S instead. This has a short extension on the AUI connector that
makes it easier to plug into a Sun. This is what I recommended in an
earlier response to this post.

Z

Lars Poulsen

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Mar 8, 1994, 6:01:04 AM3/8/94
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In article <chR1_wC00...@andrew.cmu.edu> Derrick J. Brashear,
db...@andrew.cmu.edu writes:
>>: >I have 2 machines here with free AUI ports, and I'd like to connect
>>: >*just* these two machines, i.e., there is no need for anything beyond a
>>: >connection to these two machines. What I'd like to know is, what is the
>>: >absolute cheapest way I can do it?

In article <2lfvmp$8...@news.cs.tu-berlin.de> pie...@cs.tu-berlin.de writes:
>I'm wondering if it's possible to connect them *directly* by just crossing
>the relevant lines (send-receive, etc).

While it is often possible, it is not particularly robust, and it is
very easy to make mistakes that damage the equipment.

If you know enough to have a really good idea of which pins ought to
be conencted, and you have the tools to make cables, then you probably
also have the skills to do it safely and to troubleshoot it, if it
doesn't work. (I did this, about 10 years ago, when I was testing out
a prototype Ethernet controller for an IBM channel, in a LAB without
a "live" ethernet, and could not afford a hub. But at today's prices
for BNC transceivers, it isn't worth the risk to the equipment.)

If you have to ask about pin numbers, I would very strongly advise
against trying this on your own !!
--
/ Lars Poulsen Internet E-mail: la...@CMC.COM
CMC Network Products Phone: (011-) +45-31 49 81 08
Hvidovre Strandvej 72 B Telefax: +45-31 49 83 08
DK-2650 Hvidovre, DENMARK Internets: designed and built while you wait

Jay Hennigan

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Mar 11, 1994, 5:22:54 PM3/11/94
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In article <1994Mar8.1...@eskimo.cph.cmc.com> la...@Eskimo.CPH.CMC.COM
(Lars Poulsen) writes:
>In article <2lfvmp$8...@news.cs.tu-berlin.de> pie...@cs.tu-berlin.de writes:
>>I'm wondering if it's possible to connect them *directly* by just crossing
>>the relevant lines (send-receive, etc).
>
>While it is often possible, it is not particularly robust, and it is
>very easy to make mistakes that damage the equipment.

What makes it non-robust? As I understand it, an AUI cable is essentially
four twisted pairs. Would not a "crossover cable" be inherently simpler
and less failure-prone than a number of inter-series adapters? And are
the line drivers and receivers in the equipment so fragile that a
mis-wired cable could indeed do damage? Would an over-zealous installer
putting a staple through a drop cable to a thicknet trunk also be capable
of causing hardware damage?

>If you know enough to have a really good idea of which pins ought to
>be conencted, and you have the tools to make cables, then you probably
>also have the skills to do it safely and to troubleshoot it, if it
>doesn't work. (I did this, about 10 years ago, when I was testing out
>a prototype Ethernet controller for an IBM channel, in a LAB without
>a "live" ethernet, and could not afford a hub. But at today's prices
>for BNC transceivers, it isn't worth the risk to the equipment.)
>
>If you have to ask about pin numbers, I would very strongly advise
>against trying this on your own !!

I, too have a similar need, and turned to this newsgroup for the express
purpose of asking about pin numbers! Tell us about your experience of 10
years ago. I've got plenty of experience in making cables and the right
tools, but just need the pin numbers if in fact it is doable.

As an alternative to rolling one's own, is there a "null modem" type of
adapter on the market that could be used with a standard AUI extension
cable, already correctly wired? If not, it seems as if there is at least
a warm market for one.


Matthew Deter

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Mar 13, 1994, 12:45:17 PM3/13/94
to
Jay Hennigan (j...@coyote.rain.org) wrote:

: I, too have a similar need, and turned to this newsgroup for the express

: purpose of asking about pin numbers! Tell us about your experience of 10
: years ago. I've got plenty of experience in making cables and the right
: tools, but just need the pin numbers if in fact it is doable.

The following is a reply I received when I asked this exact same
AUI <-> AUI "null modem" question a while back. (I forget which group
I asked on...)

I **DID NOT** try out this wiring diagram, as the need evaporated
before I had a chance to try it out. (I found some BNC transceivers
laying around. :-)

**Try this at your own risk.**

---BEGIN INCLUDE---

From ayeo...@vnet.IBM.COM Wed Oct 6 02:43:18 1993
Date: Wed, 6 Oct 93 10:42:20 BST
From: "Andrew J V Yeomans" <ayeo...@vnet.IBM.COM>
Subject: AUI <-> AUI cabling question

I've done the following, and got it to work. No promises, try at your
own risk!

Shield 1 1 Shield
Collision Detect A 2 2 Collision Detect A
Transmit Data A 3 ----\ /---- 3 Transmit Data A
(Receive Data Shield) 4 X 4 (Receive Data Shield)
Receive Data A 5 ----/ \---- 5 Receive Data A
Vc 6 --- --- 6 Vc
(Control Out A) 7 | | 7 (Control Out A)
(Control Out Shield) 8 | | 8 (Control Out Shield)
Collision Detect B 9 --- --- 9 Collision Detect B
Transmit Data B 10 ----\ /---- 10 Transmit Data B
(Transmit Data Shield) 11 X 11 (Transmit Data Shield)
Receive Data B 12 ----/ \---- 12 Receive Data B
V+ 13 13 V+
(V Shield) 14 14 (V Shield)
(Control Out B) 15 15 (Control Out B)
--
Andrew Yeomans 081-818 4288 NOSS/VNET: BASVM1(YEOMANA)
Internet: AYeo...@vnet.ibm.com IEA: GBIBML89 at IBMMAIL
IBM Ltd, 1 New Square, Bedfont Lakes, Feltham, Middx, TW14 8HB

---END INCLUDE---
--
$$ Matthew Deter
$$$$ m...@netcom.com
$$
$$$$ "The fortune of my spirit is not to be blown into coins of brass
$$ and flung to the winds as alms for the poor of the spirit."
$$$$
$$ -- from the novel _Anthem_ by Ayn Rand

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