From: themos@umbc5.umbc.edu (Mr. Themos Pentakalos; ADMIN-COMP)
Subject: Converting from TP to AUI or BNC (NICs)
Organization: Univ. of MD, Baltimore County
Date: Mon, 16 Nov 1992 19:29:18 GMT

HI everyone,

	A few weeks ago I posted a request for info on converters
so I can use TP RJ45 to connect NICs which only have BNC and AUI on them.
I delayed summarizing since the answers didn't stop comming in until
last week.

	Twentynine people answered to my question and I thank each
and everyone!

	Themos

From: John Lauro <jal@acc2.flint.umich.edu>

Cabletron makes a converter that can support up to 10 machines on a
segment.  However, Asante' makes a repeater (so it can handle 28
devices) for only about $200.  It's more then an ethernet card, but
less then several ethernet cards...  It will depend if you can put
multiple machines in the same office or not...

From: ingram@cs.duke.edu (Robert E. Ingram)

You will probably get a lot of "yes" answers to this, so ill add one
more, but in addition, i have experience with two such devices.

The Cabletron CTP100T is a flat (3/4") box, about 4 x 7. It has a switch
allowing you to terminate internally or externally, has the very readable
LANview (TM) LED's, & a nice little users manual.
Price: $375

Lantronix offers a 2-pice unit, known collectively as LTX-C2. It is a 10BaseT
to AUI Converter, with an ordinary Thinnet xcvr plugged directly in. It wobbles
a bit, but its smaller & the kicker--
Price: $186.75

All devices of this type require power. Note also that prices have educational
discount. If you go with the Cabletron here's a little tip. It tends to jam
when initially connected. Power cycle that little sucker & it'll clear.

I hope this helps.

Date: Wed, 4 Nov 92 06:58:09 PST

You can buy something that converts from twisted pair (rj45) to thinwire
(BNC), but that really isn't what you want.  You want a twisted pair transceiver
that goes onto the AUI interface (the 15 pin DB15 connector on the card).
The best price I've seen on these is through a company called St. Clair.
They have such critters for $39.95.  Contact St. Clair at 412-835-5000.
We have some of their transceiver and, despite the low price work just
fine.

Good Luck,

 -Dale

From: Aaron Leonard <LEONARD@arizona.edu>

Yes there are such devices, but you won't like the price tag - about
$250-350 each.

There are two types of devices with a 10baseT RJ45 jack on one side
and a ThinWire BNC on the other - media adapters and repeaters.
Each allows you to plug some number of daisy-chained ThinWire
stations onto the end of a 10baseT UTP run.

A full repeater typically goes for $300-350.  It allows you to connect
a full-sized ThinWire segment (up to 29 stations, up to 185 meters)
to a full-length (100 meter) 10baseT run.  The downsides are cost and 
the fact that they increase your repeater count (never forget the 
4-repeater rule!), which may necessitate the insertion of bridges.

A media adapter is somewhat cheaper, around $250-300.  It is not a
repeater but a "plug and pray" device that simply converts the
signal between the dissimilar media types.  It does not increase
your repeater count.  However, as the jitter budget of the ThinWire
segment is "stolen" from that of the UTP run, you wind up with 
tradeoffs between the UTP run length, the number of ThinWire stations,
and the length of the ThinWire segment.  For example, you may be
able to attach a 70 meter ThinWire with 12 stations to a 50-meter
UTP run, but only one ThinWire station on a 1 meter ThinWire onto
a 90-meter UTP run.

It may well be cheaper for you to pitch your ThinWire NICs and get
10baseT ones.

Best,

Aaron

From: teddybur@netcom.com (John Sanger)

Yes, many of the companies that make ethernet cards and converters  and
such have the devices to do this.  Clair and Allied Telesis are just 2 of
them.  Clair is the most inexpensive of the two.


Ciao!
	John S. :^)

From: teddybur@netcom.com (John Sanger)

Yes it is cheaper.  I have Clair convertors to go from the aui connector to
the rj45 which I am cabling my office with.  My cards are $895.00 each so
for $39.95 each I have converted them to 10baseT .
Oh, it is St. Clair Systems Corp. at 2680 Marshfield Drive, Pittsburgh, PA
15241, (412) 835-5000.

Ciao!
	John S. :^)

From: sweeney@ingres.com (Tony Sweeney)

Yup. The little yoke connecting me to the world is called an:

Ethernet
10BaseT
Micro-ceiver

and is made by Transition Engineering Inc. I could probably find
out how much we paid for them. These are powered straight from
the AUI (if there's clearance to plug it straight onto the card), else
via drop cable. We have a couple that go from BNC to RJ45, but I 
imagine these are more 'spensive, since they each have their own little
external mains power supply. You probably get to re-jumper your 
Ethernet card to AUI for it to work. Transition are at:

7090 Shady Oak Road,
Eden Prairie,
MN 55344
Tel. (612) 941 7600
Tel. (800) 325 2725
Fax. (612) 941 2322


Hope this helps.

Tony.

From: aem%symbi1.UUCP@uunet.uu.net (a.e.mossberg)

ThinNet Baluns are available from Black Box at $45/ea.  Any network
equipment place should have them...

aem

From: tclar@baddog.cca.cr.rockwell.com (Thomas G. Clark)

No. Then you would need an external transceiver instead of using the one
built in to your ethernet card. You  don't want to do this. It will be
more expensive than using a rj45-bnc balun.  If you can't justify
spending the about $45 to go from bnc to rj45 via baluns, how are you
going to justify spending about $80-$100 for external transceivers?  And
if the money isn't an issue, then you should do it right and get
ehternet cards with built-in twisted pair!

aem

From: BARR DOUG <barr@tramp.colorado.edu>

If your ethernet card has an AUI port you may attach a TRANSIEVER to this
port. The transiever may be a twisted pair, thinwire or fiber optic.
This device has an AUI port on one side and the twisted pair (or other)
port on the other. They go for about $100. Try and get one with a link,
transmit, recieve, collision and SQE led. That way you can observe the
traffic and problems by looking at your transiever lights. You may need
a short AUI cable if you do not have room between the workstation and the
wall for the transiever. I recommend Cabletron, Milan, and Allied Telesis.

From: Aaron Leonard <LEONARD@arizona.edu>

Themos:

This time you asked the right question.  Yes, it would be MUCH better
for you to use the AUI port.  All you need to do is to order a 
"10baseT MAU", for each station, which typically costs between
$50 - 100 each.

The best deal I've seen is from St. Clair - only $39.95 each.
(1-800-326-5367).  Caveat: I haven't used any of these, so
I can't verify that they work correctly.  However, I've got 
a couple on order right now.

Best,

Aaron

From:	SMTP%"pat+@transarc.com"  4-NOV-1992 17:09:55.03

David Systems sells such a box.  Unfortunately, I don't have their
phone number or pricing available.

Also, St. Clair Systems has a BNC to 10BaseT converter for $369.

If you only have a couple of machines, it's probably worth it to just
change out the network cards to 10BaseT or AUI cards; otherwise, try
the converter.

From: searsk@med.ge.com (Kevin D. Sears)

Cabletron has a device called a CTP100 which will transfer from UTP to
thinnet. 
Check with them for node and distance limitations.

From: taylorb@ncifcrf.gov

Cabletron makes a transceiver called a TPT that converts 10BaseT to
ThickNet (AUI) that costs about 80 bucks.  We use em all the time.......

From: Aaron_Dailey%stortek.UUCP@csn.org (Aaron Dailey)

Black Box, at (412) 746-5500 makes such a device.  We've used them,
and they work well.  They are about $300 a piece though.  You can put
several thinnet computers on one box though.

From: Ed Richardson <ed@delfin.com>

We recently went through the same process.

There are transceivers which attach directly to an AUI port on your
Ethernet board.  The TP cable plugs into the transceiver.  For us, this
was less expensive than buying all new controllers.

Our controllers had both BNC and AUI ports.  If your boards only have BNC,
this won't work.

There are Coax to TP converters available.  With one of these, you could have
several machines connected with coax, then feed the coax to the converter to
connect to the TP wiring.  We are also using this approach in some areas
of our building.

The products we are using are both made by MiLAN Technology in Sunnyvale,
CA.
          MIL-10P  10BaseT Transceiver
          MIL-120A Coax to 10BaseT Converter

Try calling Wendy Miller at 408-752-2760.

From: Frank Eugene Kietzke <fk03+@andrew.cmu.edu>

St. Clair
1751 North Highland Road
Pitttsburgh, Pa 15241
(412)835-5000

AUI to 10BASE-T and
AUI to 10BASE-2 

$39.95 according to the catalog I just received

From: dave%major.panix.com@panix.com (Dave O'Shea)

Cabletron (Manchester, NH - 603-332-9400) makes such a device, called a TPT-4.
comes with a stubby AUI cable directly attached to it, or they make one
slightly smaller and cheaper. The TPT-4 is something like $100, discounted.

From: gmansoor@cal state northridge   (George Mansoor)

	Do you have an AUI connector on those cards?   If you do you can 
use the CentreCom 210T tp transceiver from Allied Telesis.  That's what I 
use, and they work great.

George

From: Aaron_Dailey%stortek.UUCP@csn.org (Aaron Dailey)

You just need a transceiver to go from AUI to UTP.  These are nearly
commodity items - you should be able to get one for ~$80.  Black Box
at $140 has good service and quality but for a price.

From: Andy Gutman <andyg@corollary.com>

	Sir,
		Try IMC Networks (Irvine, CA) 800/624-1070 or
		714/724-1070.

From: Jeff@digtype.airage.com (Jeff Wasilko)

Cabletron has small AUI transceivers. They're in the $100 range./...

From: tony@mpg.phys.hawaii.edu (Antonio Querubin)

10Base-T transcievers are very inexpensive nowadays, roughly $100 or less.
However, you would need a hub at the central wiring closet to connect your
network together.  12-port hubs run for around $1000 or less depending on
what kind of features you want.

From: billp@Syntex.COM              

Themos,

I bet most of your NIC cards have a 15 pin AUI connector as well.  I'd
get 10baseT tranceivers to plug into that connector.  I have seen some
converters that clame to convert between Thin Ethernet and 10baseT but
the ones I tried from Ungarman-Bass didn't work.  There are some people
that make active converters that are really two port repeaters that no
doubt work but they are more expensive (~$300) than a 10baseT tranceiver.
10baseT tranceivers should be under $100.  I've seen them as low as $50.

From: Brian Toomey              #### <BToomey@chipcom.com>

Chipcom makes two kinds of AUI to 10BASET tranceivers.  One is the standard 
type you'll here about from most companies, the other is a fault tolerant 
tranceiver which allows you to create two connections to the device with one 
in standby (redundant mode).

Many companies now make these devices: Cabletron, Synoptics, Allied Telesis, 
etc..

From: cacci@interlan.interlan.com (Ernie Cacciapuoti)

Black Box Corp. (tech supp line 412-746-5565) has an adapter   

From: cacci@interlan.interlan.com (Ernie Cacciapuoti)

So now you tell me!! Okay, WE have one of those guys -- it's called a 
Micro Mau and I think it's around $100 -- just call the number
above for "pre-sales support to find where your nearest vendor is.