Re: Ethernet cable (Was: Sun3 valuations?)

[Al Kossow via cctalk]

On 1/24/18 1:05 PM, Brent Hilpert via cctalk wrote:

> I haven't seen any pictures during this thread of the transceivers we used 
> with the 10MB yellow hose - heavy gauge metal boxes about 3" * 4" * 1" with N 
> connectors. I remember piling up the 3 ft diameter loops of yellow coax in 
> the machine room where you had a bunch of machines together and didn't need 
> the cable lengths between them, until the DEC DELNI (ethernet AUI hub) 
> cleaned up that mess.
> 

likely 3Com

http://www.piercefuller.com/library/10126.html


ones with vampire taps

http://www.computerhistory.org/collections/catalog/102625376
is the dec H4000

Cabletron ST-500
http://www.computerhistory.org/collections/catalog/102642433
http://www.computerhistory.org/collections/catalog/102677160
also was availble with N connectors

http://www.computerhistory.org/collections/catalog/102682788
dec H4005

Re: Ethernet cable (Was: Sun3 valuations?)

[Glen Slick via cctalk]

On Wed, Jan 24, 2018 at 1:05 PM, Brent Hilpert via cctalk
 wrote:
>
> I haven't seen any pictures during this thread of the transceivers we used 
> with the 10MB yellow hose - heavy gauge metal boxes about 3" * 4" * 1" with N 
> connectors.

I have a 3COM 3C100 transceiver that must have come along with some
old Sun servers I acquired a few years back. It's a heavy black box
about 4" x 5" x 1" with two N connectors and the 15-pin AUI connector.
I opened it up just now to look inside to see why it is so heavy. The
whole thing is potted inside with a solid black compound so there is
nothing to see.

Re: Ethernet cable (Was: Sun3 valuations?)

[Paul Koning via cctalk]

> On Jan 24, 2018, at 4:05 PM, Brent Hilpert via cctalk  
> wrote:
> 
> On 2018-Jan-23, at 12:27 PM, Paul Koning via cctalk wrote:
>> The Ethernet spec says that the cable OD is in the range .365 to .415 inch, 
>> which is 9.27 to 10.54 mm.  The nominal OD of RG-8/U is .405 inches, or 
>> 10.28 mm, which is within spec for Ethernet cable.
>> 
>> One place where the two cable specs differ is in the velocity factor, 0.66 
>> for RG-8/U and 0.77 for Ethernet cable.  That relates to the dielectric -- 
>> solid polyethylene for RG-8/U and foamed material (unspecified) for 
>> Ethernet.  Also, Ethernet requires a solid inner conductor (for the tap) 
>> while RG-8/U may come stranded.  (Maybe only in some variants, I'm not 
>> sure.)  And there are the stripes, of course, but those have no electrical 
>> significance.  You can use a tape measure if you don't have the stripes.
> 
> I was attempting some calculations to see if I could derive the 2.5M 
> transceiver spacing and was wondering what the velocity factor for the cable 
> was, as it should affect the transceiver spacing in theory.

The velocity factor is specified as 0.77.  The Manchester encoding of 10 Mb 
Ethernet means the dominant frequency is 10 MHz, which in the coax would have a 
wavelength of 23.1 meters (0.77 * c / 10e6).  So the 2.5 meter spacing is 
0.1082 wavelengths, i.e., a number chosen NOT be be a round value.  If you look 
at the integer multiples of that value you'll find hardly any that are close to 
an integer; the first one I see is 37x which is 4.004.  This ensures that there 
is very little in the way of coincident reflections.

There are lots of other spacings that would work, for example 2.0 meters is 
also a decent choice -- all that is required is "pick a spacing such that 
nearly all the tap points are not round multiples of 1/2 wavelength of 10 MHz 
apart".  2.5 seems a fine choice given the max cable length (500 meters) and 
station count (100); there is no real benefit in picking a smaller value.

If you're using actual RG-8/U (VF = 0.66) then the answers come out different, 
of course.

paul

Re: Ethernet cable (Was: Sun3 valuations?)

[Brent Hilpert via cctalk]

On 2018-Jan-23, at 12:27 PM, Paul Koning via cctalk wrote:
> The Ethernet spec says that the cable OD is in the range .365 to .415 inch, 
> which is 9.27 to 10.54 mm.  The nominal OD of RG-8/U is .405 inches, or 10.28 
> mm, which is within spec for Ethernet cable.
> 
> One place where the two cable specs differ is in the velocity factor, 0.66 
> for RG-8/U and 0.77 for Ethernet cable.  That relates to the dielectric -- 
> solid polyethylene for RG-8/U and foamed material (unspecified) for Ethernet. 
>  Also, Ethernet requires a solid inner conductor (for the tap) while RG-8/U 
> may come stranded.  (Maybe only in some variants, I'm not sure.)  And there 
> are the stripes, of course, but those have no electrical significance.  You 
> can use a tape measure if you don't have the stripes.

I was attempting some calculations to see if I could derive the 2.5M 
transceiver spacing and was wondering what the velocity factor for the cable 
was, as it should affect the transceiver spacing in theory.

I haven't seen any pictures during this thread of the transceivers we used with 
the 10MB yellow hose - heavy gauge metal boxes about 3" * 4" * 1" with N 
connectors. I remember piling up the 3 ft diameter loops of yellow coax in the 
machine room where you had a bunch of machines together and didn't need the 
cable lengths between them, until the DEC DELNI (ethernet AUI hub) cleaned up 
that mess.

Re: Ethernet cable (Was: Sun3 valuations?)

[Al Kossow via cctalk]

And if anyone has any of the early TCL transceivers, check the tantalums
on the power supply input. I've had many failures of them.

On 1/24/18 10:38 AM, Al Kossow via cctalk wrote:
> 
> 
> On 1/24/18 10:23 AM, Grant Taylor via cctalk wrote:
>> I think that would make the transceivers slightly more usable.
> 
> It makes them a LOT more usable :-)
> 
> 

Re: Ethernet cable (Was: Sun3 valuations?)

[Al Kossow via cctalk]

On 1/24/18 10:23 AM, Grant Taylor via cctalk wrote:
> I think that would make the transceivers slightly more usable.

It makes them a LOT more usable :-)

Re: Ethernet cable (Was: Sun3 valuations?)

[Grant Taylor via cctalk]

On 01/24/2018 10:52 AM, Al Kossow via cctalk wrote:
More pics of the 3mbit transceiver, cable and pics of a 10mbit TCL 
transceiver (the original 10mbit one) are up now


Thank you for the pictures.

I really like the idea of the BNC modification.  I think that would make 
the transceivers slightly more usable.




--
Grant. . . .
unix || die

Re: Ethernet cable (Was: Sun3 valuations?)

[Al Kossow via cctalk]

More pics of the 3mbit transceiver, cable and pics of a 10mbit TCL transceiver 
(the original 10mbit one)
are up now

On 1/23/18 8:10 AM, Al Kossow via cctalk wrote:
> there are pictures of the transceiver w/o the vampire tap on bitsavers
> under http://bitsavers.org/pdf/xerox/ethernet_3mb/

Re: Ethernet cable (Was: Sun3 valuations?)

[Noel Chiappa via cctalk]

   > From: Chuck Guzis

> On 01/23/2018 04:04 PM, Al Kossow via cctalk wrote:

>> they mention they used CATV technology (where the vampire taps come
>> from)

> Wasn't that ChaosNet?

The CHAOS net (capitalization varied, but original docs usually use two words)
hardware did use the heavy-duty CATV cable (not the indoor stuff; I have a
chunk of the heavy-duty kind they used too :-), but not vampire taps; the
transceivers had T-connectors on them, and to install one, one put connectors
on the ends of the cable segments, and screwed them onto the T-connector.

Noel

RE: CX laser printers (Was: Sun3 valuations?

[Ali via cctalk]

> At least close.
> It's what Printerworks says that they use to repaint the Fedex purple
> printers back to look like the other CX based printers.   Check the

Fred,

Thanks for the info. I guess I may have to stop by the local
Sherman-Williams and see what they have!


p.s. while we are at it anybody remember what the color is for the "Apple
Platinum" machines (a la Mac IIs)?

Re: Ethernet cable (Was: Sun3 valuations?)

[Chuck Guzis via cctalk]

On 01/23/2018 04:04 PM, Al Kossow via cctalk wrote:

> There is a clue in the PARC Ethernet Blue and White about this where
> they mention they used CATV technology (where the vampire taps come
> from ) but they don't actually say there that they used 75 Ohm cable,
> terminated at both ends.

Wasn't that ChaosNet?

--Chuck

Re: Ethernet cable (Was: Sun3 valuations?)

[Al Kossow via cctalk]

On 1/23/18 4:04 PM, Al Kossow via cctalk wrote:

> He's holding up the wrong stuff if it's RG-8
> 
> Experimental Ethernet is 75 ohms.
> 

I just went out to storage and got the run of cable that was used with a Dorado.
I'll take some pics of it later.
It is orange, looks like RG-6, is Malco 98278 (Xerox PN 117P80660)
I measured the terminator resistance to be 75.0 ohms.

Re: Ethernet cable (Was: Sun3 valuations?)

[Al Kossow via cctalk]

On 1/23/18 12:27 PM, Paul Koning via cctalk wrote:
> 

>> The stuff with better shield, marking bands, etc is 10 Mb; it's about 1.05cm
>> in diagmeter. The black stuff (the stuff Dave is holding in the video) is 
>> 3Mb;
>> the piece I have is .95 cm.
> 
> The Ethernet spec says that the cable OD is in the range .365 to .415 inch, 
> which is 9.27 to 10.54 mm.  The nominal OD of RG-8/U is .405 inches, or 10.28 
> mm, which is within spec for Ethernet cable.
> 

He's holding up the wrong stuff if it's RG-8

Experimental Ethernet is 75 ohms.

see 
http://bitsavers.org/public_html/pdf/xerox/alto/ethernetEthernet_Transceiver_Electrical_Characteristics

Drive Voltage: +3 volts (Nominal) into  >> 37.5 ohms <<

There is a clue in the PARC Ethernet Blue and White about this where they 
mention they used CATV technology
(where the vampire taps come from ) but they don't actually say there that they 
used 75 Ohm cable, terminated at both ends.

Re: Ethernet cable (Was: Sun3 valuations?)

[Ethan Dicks via cctalk]

On Tue, Jan 23, 2018 at 11:12 AM, Bill Gunshannon via cctalk
 wrote:
> Vampire taps.  Now there's a blast from the past.  Somewhere around here
> I still have my toolbag which still has my tap drill for installing those 
> taps.

I also have a tap drill somewhere, but it was a rescue from a
clean-out.  I've never installed any Thicknet... so far.

I did pick up a bit of yellow 10mbit cable at VCF Midwest a couple
years back, and a couple of taps.  I wish I had one more to make it
interesting.  I do have some of the boxy transceivers but with 10Base2
BNCs on the mounting plate that can also take a vampire tap mounting
plate.

One of my long-term low-priority projects is to mount that Ethernet
segment high up on a wall, display fashion, and have 2-3 stations and
AUI cables hanging down to table height for interconnecting vintage
networking gear.  I do have 10BaseT hubs with AUI ports and even one
or two AUI<->Fiber MAUs to make it all interesting.

Something I have that may be of interest here is a small box of
N-connector 50 Ohm terminators.  I can't ever imagining needing more
than 2 pair for my entire life, so if anyone wants to swap for vintage
network hardware, let me know.  Mostly, I really want one or two of
the clamp-on vampire taps, the kind you could unscrew from the
transceiver (so that you never had to disturb the tap but you could
remove a station).

The last time I knew I was using Etherhose was at the South Pole in
1996 - they had a long run of it before they switched all the building
interconnects to fiber.  It's probably still buried there.

-ethan

Re: Ethernet cable (Was: Sun3 valuations?)

[Bill Gunshannon via cctalk]

I hope they all weren't on that yellow cable.  @60 devices on a single
collision domain would likely not have worked very well.

I also can't believe you used Ethernet RG8 for ham radio.  I read the
spec and even tried some (I had reels of that stuff at one time) and
found it way too lossy even at HF frequencies.  It was very low quality
RG8.

bill
KB3YV


From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Pete Lancashire via 
cctalk <cctalk@classiccmp.org>
Sent: Tuesday, January 23, 2018 3:51 PM
To: Noel Chiappa; General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Ethernet cable (Was: Sun3 valuations?)

A side story. I was the only 'customer' of a long run of that yellow cable,
when we moved the 260 + 3/50's to a different location, I asked
if they were going to reuse the cable. "Nope, cost to much to get it out of
the roof trusses." I forget but it was a LONG run. Tektronix
back in those days was still an engineering oriented company and all I had
to do was mention it one day in the main cafeteria. Next
thing I know I was followed back to the building with at least 10 engineers
following me. I called and asked one one the facility department
guys that knew about the cable no longer being used, and his reply was
something like if it not there Monday I know nothing about it.

The bottom of the trusses were a good 15 if not more feet up. Five of us
got it down and I came home with the cable on Sunday.
My helpers would not take anything in $'s, the challenge was good enough.

Make a great cable for my ham radio hobby.

Today one would never get away with such 

-pete



On Tue, Jan 23, 2018 at 12:39 PM, Noel Chiappa via cctalk <
cctalk@classiccmp.org> wrote:

> > From: Paul Koning
>
> > The nominal OD of RG-8/U is .. within spec for Ethernet cable.
>
> Oh, OK. I was just used to the 10Mb cable we used being slightly larger
> than
> the 3Mb cable we used.
>
> > Also, Ethernet requires a solid inner conductor (for the tap) while
> > RG-8/U may come stranded. (Maybe only in some variants, I'm not
> sure.)
>
> As can be seen in the photos, the 3Mb stuff (at least, the stuff we used)
> was
> also solid. The diameter of the center was a little smaller on the 3Mb
> than on
> the 10Mb; .16mm versus .23mm; not sure if that was just happenstance, or
> what.
>
> Noel
>
>

Re: Ethernet cable (Was: Sun3 valuations?)

[Grant Taylor via cctalk]

Nice story.

On 01/23/2018 01:51 PM, Pete Lancashire via cctalk wrote:

Today one would never get away with such 


I don't know.  I've had to mine out quite a bit of old cable that was 
abandoned in place to make room for new installations.  Frequently the 
building owners were more than happy to see it disappear in a fashion 
that meant that I didn't have to bill them for my time to pull it out.


Day 1:  Man, we have to move get this crap out of the way so that we can 
do our install.
Day 2:  Meetings.  (While interested parties pull out the cable and 
leave a surprise.)
Day 3:  Hay, I thought you said that we needed to mine something.  I it 
looks like clear haul.  ...and someone left a pull string that we can 
use.  Suckers.  ;-)




--
Grant. . . .
unix || die

Re: Ethernet cable (Was: Sun3 valuations?)

[Pete Lancashire via cctalk]

A side story. I was the only 'customer' of a long run of that yellow cable,
when we moved the 260 + 3/50's to a different location, I asked
if they were going to reuse the cable. "Nope, cost to much to get it out of
the roof trusses." I forget but it was a LONG run. Tektronix
back in those days was still an engineering oriented company and all I had
to do was mention it one day in the main cafeteria. Next
thing I know I was followed back to the building with at least 10 engineers
following me. I called and asked one one the facility department
guys that knew about the cable no longer being used, and his reply was
something like if it not there Monday I know nothing about it.

The bottom of the trusses were a good 15 if not more feet up. Five of us
got it down and I came home with the cable on Sunday.
My helpers would not take anything in $'s, the challenge was good enough.

Make a great cable for my ham radio hobby.

Today one would never get away with such 

-pete



On Tue, Jan 23, 2018 at 12:39 PM, Noel Chiappa via cctalk <
cctalk@classiccmp.org> wrote:

> > From: Paul Koning
>
> > The nominal OD of RG-8/U is .. within spec for Ethernet cable.
>
> Oh, OK. I was just used to the 10Mb cable we used being slightly larger
> than
> the 3Mb cable we used.
>
> > Also, Ethernet requires a solid inner conductor (for the tap) while
> > RG-8/U may come stranded. (Maybe only in some variants, I'm not
> sure.)
>
> As can be seen in the photos, the 3Mb stuff (at least, the stuff we used)
> was
> also solid. The diameter of the center was a little smaller on the 3Mb
> than on
> the 10Mb; .16mm versus .23mm; not sure if that was just happenstance, or
> what.
>
> Noel
>
>

Re: Ethernet cable (Was: Sun3 valuations?)

[Grant Taylor via cctalk]

On 01/23/2018 01:39 PM, Noel Chiappa via cctalk wrote:
As can be seen in the photos, the 3Mb stuff (at least, the stuff we used) 
was also solid. The diameter of the center was a little smaller on the 
3Mb than on the 10Mb; .16mm versus .23mm; not sure if that was just 
happenstance, or what.


That (and the OD) sounds like standard manufacturer to manufacturer 
variation in different RG-8 grade cables that meet / fall within the 
electrical / transmission / physical specifications of RG-8 cable.


I expect that the "yellow hosepipe" as I've heard the 10 Mbps coax 
referred to as being a subset, possibly more stringent, of Radio Grade 8 
coax cable.




--
Grant. . . .
unix || die

Re: Ethernet cable (Was: Sun3 valuations?)

[Noel Chiappa via cctalk]

> From: Paul Koning

> The nominal OD of RG-8/U is .. within spec for Ethernet cable.

Oh, OK. I was just used to the 10Mb cable we used being slightly larger than
the 3Mb cable we used.

> Also, Ethernet requires a solid inner conductor (for the tap) while
> RG-8/U may come stranded. (Maybe only in some variants, I'm not sure.)

As can be seen in the photos, the 3Mb stuff (at least, the stuff we used) was
also solid. The diameter of the center was a little smaller on the 3Mb than on
the 10Mb; .16mm versus .23mm; not sure if that was just happenstance, or what.

Noel

Re: Ethernet cable (Was: Sun3 valuations?)

[Paul Koning via cctalk]

> On Jan 23, 2018, at 3:19 PM, Noel Chiappa via cctalk  
> wrote:
> 
>> From: Grant Taylor
> 
>> I can fairly clearly see the RG-8/U on the side of the cable that David
>> is holding ... Sure, there was probably a better alternative that came
>> along after, with better shielding and marking bands. 
> 
> You keep mixing up the 3 Mbit and 10 Mbit. _They were not the same_. (I
> _really_ need to retake those photos with a ruler in them...)
> 
> The stuff with better shield, marking bands, etc is 10 Mb; it's about 1.05cm
> in diagmeter. The black stuff (the stuff Dave is holding in the video) is 3Mb;
> the piece I have is .95 cm.

The Ethernet spec says that the cable OD is in the range .365 to .415 inch, 
which is 9.27 to 10.54 mm.  The nominal OD of RG-8/U is .405 inches, or 10.28 
mm, which is within spec for Ethernet cable.

One place where the two cable specs differ is in the velocity factor, 0.66 for 
RG-8/U and 0.77 for Ethernet cable.  That relates to the dielectric -- solid 
polyethylene for RG-8/U and foamed material (unspecified) for Ethernet.  Also, 
Ethernet requires a solid inner conductor (for the tap) while RG-8/U may come 
stranded.  (Maybe only in some variants, I'm not sure.)  And there are the 
stripes, of course, but those have no electrical significance.  You can use a 
tape measure if you don't have the stripes.

paul

Re: Ethernet cable (Was: Sun3 valuations?)

[Bill Gunshannon via cctalk]

That's what I get for cutting and pasting from a Google search.
Sorry...

bill


From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Bill Gunshannon via 
cctalk <cctalk@classiccmp.org>
Sent: Tuesday, January 23, 2018 2:22 PM
To: Grant Taylor via cctalk; Grant Taylor
Subject: Re: Ethernet cable (Was: Sun3 valuations?)

If you want a real hoot try reading what

<https://books.google.com/books?id=tmbgBwAAQBAJ=PA212=PA212=what+was+the+purpose+of+the+black+bands+on+ethernet+cables?=bl=DV53aRJc9P=3GFr8Hz_uQjFELOrnXk8x8KjKVM=en=X=0ahUKEwj-i_j_5u7YAhVD34MKHeSQC-wQ6AEIWzAG>
"A System Administrator’s Guide to Sun 
Workstations"<https://books.google.com/books?id=tmbgBwAAQBAJ=PA212=PA212=what+was+the+purpose+of+the+black+bands+on+ethernet+cables?=bl=DV53aRJc9P=3GFr8Hz_uQjFELOrnXk8x8KjKVM=en=X=0ahUKEwj-i_j_5u7YAhVD34MKHeSQC-wQ6AEIWzAG>

has to say about it.  Google has it available for reading.

bill


From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Grant Taylor via 
cctalk <cctalk@classiccmp.org>
Sent: Tuesday, January 23, 2018 2:13 PM
To: cctalk@classiccmp.org
Subject: Re: Ethernet cable (Was: Sun3 valuations?)

On 01/23/2018 12:09 PM, Bill Gunshannon via cctalk wrote:
> "Transceivers should be installed only at precise 2.5-metre
> intervals. This distance was chosen to not correspond to the wavelength
> of the signal; this ensures that the reflections from multiple taps are
> not in phase. These suitable points are marked
>  on the cable with black bands."
>
> It cites "IEEE Standard 802.3<https://en.wikipedia.org/wiki/802.3>-1985.
> IEEE<https://en.wikipedia.org/wiki/IEEE>. p. 121."

Thank you for correcting ~> educating me.

#learnSomethingEveryDay



--
Grant. . . .
unix || die

Re: Ethernet cable (Was: Sun3 valuations?)

[Grant Taylor via cctalk]

On 01/23/2018 12:07 PM, Marc Verdiell via cctalk wrote:
Have you seen this part of the video where David Boggs (designer of the 
first 3 Mb Ethernet card for the Alto), and Ron Crane (designer of the 
10 Mb Ethernet) are doing a show and tell in their own words? You get 
to see the clamps, the drill, the transceivers, the cards, and some of 
the inventors. Regrettably Ron passed away a few month after we took 
the video. We still miss him.  https://youtu.be/XhIohWr10kU?t=4m27s


I really liked that video, and the entire Alto restoration series from 
CuriousMarc.


I've got to say, I think David Boggs saying "…very simple off the shelf 
stuff, for people who want to know, it's RG-8. … This is the 50 Ω 
version of it."  I can fairly clearly see the RG-8/U on the side of the 
cable that David is holding at 8:01.  That's good enough for me.


Sure, there was probably a better alternative that came along after, 
with better shielding and marking bands.  But it sounds like RG-8/U is 
definitive acceptable to me.  I'll assume that David meant quality RG-8.


What I don't know is if RG-8/U was used for 3 Mbps and then something 
else was used for 10 Mbps.




--
Grant. . . .
unix || die

Re: Ethernet cable (Was: Sun3 valuations?)

[Bill Gunshannon via cctalk]

If you want a real hoot try reading what

<https://books.google.com/books?id=tmbgBwAAQBAJ=PA212=PA212=what+was+the+purpose+of+the+black+bands+on+ethernet+cables?=bl=DV53aRJc9P=3GFr8Hz_uQjFELOrnXk8x8KjKVM=en=X=0ahUKEwj-i_j_5u7YAhVD34MKHeSQC-wQ6AEIWzAG>
"A System Administrator’s Guide to Sun 
Workstations"<https://books.google.com/books?id=tmbgBwAAQBAJ=PA212=PA212=what+was+the+purpose+of+the+black+bands+on+ethernet+cables?=bl=DV53aRJc9P=3GFr8Hz_uQjFELOrnXk8x8KjKVM=en=X=0ahUKEwj-i_j_5u7YAhVD34MKHeSQC-wQ6AEIWzAG>

has to say about it.  Google has it available for reading.

bill


From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Grant Taylor via 
cctalk <cctalk@classiccmp.org>
Sent: Tuesday, January 23, 2018 2:13 PM
To: cctalk@classiccmp.org
Subject: Re: Ethernet cable (Was: Sun3 valuations?)

On 01/23/2018 12:09 PM, Bill Gunshannon via cctalk wrote:
> "Transceivers should be installed only at precise 2.5-metre
> intervals. This distance was chosen to not correspond to the wavelength
> of the signal; this ensures that the reflections from multiple taps are
> not in phase. These suitable points are marked
>  on the cable with black bands."
>
> It cites "IEEE Standard 802.3<https://en.wikipedia.org/wiki/802.3>-1985.
> IEEE<https://en.wikipedia.org/wiki/IEEE>. p. 121."

Thank you for correcting ~> educating me.

#learnSomethingEveryDay



--
Grant. . . .
unix || die

Re: Ethernet cable (Was: Sun3 valuations?)

[Grant Taylor via cctalk]

On 01/23/2018 12:09 PM, Bill Gunshannon via cctalk wrote:
"Transceivers should be installed only at precise 2.5-metre 
intervals. This distance was chosen to not correspond to the wavelength 
of the signal; this ensures that the reflections from multiple taps are 
not in phase. These suitable points are marked 
 on the cable with black bands."


It cites "IEEE Standard 802.3-1985. 
IEEE. p. 121."


Thank you for correcting ~> educating me.

#learnSomethingEveryDay



--
Grant. . . .
unix || die

Re: Ethernet cable (Was: Sun3 valuations?)

[Bill Gunshannon via cctalk]

>From Wiki:
"Transceivers should be installed only at precise 2.5-metre intervals. This 
distance
was chosen to not correspond to the wavelength of the signal; this ensures that 
the
reflections from multiple taps are not in phase. These suitable points are 
marked
 on the cable with black bands."

It cites "IEEE Standard 802.3<https://en.wikipedia.org/wiki/802.3>-1985. 
IEEE<https://en.wikipedia.org/wiki/IEEE>. p. 121."

bill


From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Pete Turnbull via 
cctalk <cctalk@classiccmp.org>
Sent: Tuesday, January 23, 2018 1:54 PM
To: cctalk@classiccmp.org
Subject: Re: Ethernet cable (Was: Sun3 valuations?)

On 23/01/2018 16:48, Grant Taylor via cctalk wrote:
> On 01/23/2018 09:10 AM, Bill Gunshannon via cctalk wrote:
>> If you didn't locate the transceivers on those black marks you would
>> have had terrible performance as that affects collisions.  Timing
>> (among other things like grounding) was very important with that
>> version of ethernet hardware.
>
> It's my understanding that the marks (black bands or other markings on
> the sheath) were exactly one wavelength apart.  Which from what I
> remember ~> understand from my ham radio days is quite important.

No, that's quite wrong.  The marks are every 2.5m (8.2 feet) wich IIRC
is 1/19th of a wavelength apart, the point being to try to minimise the
likelihood of connections being made where they'd suffer constructive
(additive) interference and to prevent transceivers being too close
together.

--
Pete
Pete Turnbull

Re: Ethernet cable (Was: Sun3 valuations?)

[Paul Koning via cctalk]

> On Jan 23, 2018, at 11:10 AM, Bill Gunshannon via cctalk 
>  wrote:
> 
> If you didn't locate the transceivers on those black marks you would
> have had terrible performance as that affects collisions.  Timing (among
> other things like grounding) was very important with that version of
> ethernet hardware.
> 
> bill

Yes, the purpose of the marks is to make the collision mechanism reliable.

Ethernet does not have any critical timing; collisions do not depend on timing. 
 The black stripes on official Ethernet cable exists for a different reason: to 
get you to place the taps at positions that are NOT round multiples of a 
quarter wavelength.  The reason: a tap is a (small) impedance bump, which 
causes reflections on the cable.  If you have a lot of taps and they are spaced 
multiples of a wavelength apart, those reflections will combine to produce a 
large reflection, which if you're unlucky will look like a collision.  If you 
pick the correct spacing, the reflections from the various taps are spread out 
across time and don't combine, so none of them add up to a strong enough pulse 
to be seen as a collision.

This is clearly stated in the Ethernet V2 spec, section 7.6.2:

> Coaxial cables marked as specified in 7.3.1.1.6 have marks at regular 2.5 
> meters spacing; a transceiver may be placed at any mark on the cable. This 
> guarantees both a minimum spacing between transceivers of 2.5 meters, as well 
> as controlling the relative spacing of transceivers to insure non-alignment 
> on fractional wavelength boundaries.

Reading between the lines, it's clear you could ignore those marks and get away 
with it in many cases.  Low tap count, for example.  Other positioning that 
meets the "non-alignment" intent.  But for large installations, using the marks 
ensures that you stay out of trouble.

The need to have a transmission line with controlled reflections is also why 
the cable is required to be terminated with accurate terminating resistors, at 
both end points (but not at any other point :-) ) and why splices are made with 
constant impedance connectors (N connector barrels).

Apart from the marks, the 10Base5 cable is pretty ordinary.  It's not exactly 
RG-8/U but it is not all that differen either, and if the diameter is close 
enough something like RG-8/U would make an acceptable substitute.

The same sort of considerations could apply to 10Base2, but there things are 
not as strict because the cable is shorter and the station count is 
significantly lower (max of 30).  So the spec simply states that stations 
should be at least 1/2 meter apart, and that there must not be a significant 
stub (more than a few centimeters) between the T connector and the transceiver 
electronics.

If you build with transmission line design rules in mind, you can make Ethernet 
buses out of cable of your choice, so long as it's 50 ohms and good quality 
components are used throughout.  You can, for example, splice 10Base5 to 
10Base2 (with a barrel, not a T) if you follow the more restrictive of the two 
configuration rules.

paul

RE: Ethernet cable (Was: Sun3 valuations?)

[Marc Verdiell via cctalk]

Noel,
Have you seen this part of the video where David Boggs (designer of the first 3 
Mb Ethernet card for the Alto), and Ron Crane (designer of the 10 Mb Ethernet) 
are doing a show and tell in their own words? You get to see the clamps, the 
drill, the transceivers, the cards, and some of the inventors. Regrettably Ron 
passed away a few month after we took the video. We still miss him.
https://youtu.be/XhIohWr10kU?t=4m27s
Marc

-Original Message-
From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Al Kossow via 
cctalk
Sent: Tuesday, January 23, 2018 8:10 AM
To: cctalk@classiccmp.org
Subject: Re: Ethernet cable (Was: Sun3 valuations?)

there are pictures of the transceiver w/o the vampire tap on bitsavers under 
http://bitsavers.org/pdf/xerox/ethernet_3mb/

On 1/23/18 7:51 AM, Noel Chiappa via cctalk wrote:
> > From: Grant Taylor
> 
> > According to the following page, it was not RG-8 cable ... As such it
> > was purpose built.
> 
> The 10MBit cable, yes; it was custom (you can see 'Ethernet' printed 
> on the chunk in the picture). (I'd forgotten about the black stripes! 
> I'm not sure we really bothered to follow that.)
> 
> The earlier 3Mbit I'm not so sure about - that has the air of standard 
> commercial coax.
> 
> I wish there was a picture of a 3Mbit transceiver, clamp-on holder, 
> etc! Does the CHM or LCM have them with their Alto stuff?
> 
>   Noel
> 

Re: Ethernet cable (Was: Sun3 valuations?)

[Grant Taylor via cctalk]

On 01/23/2018 09:10 AM, Bill Gunshannon via cctalk wrote:
If you didn't locate the transceivers on those black marks you would 
have had terrible performance as that affects collisions.  Timing (among 
other things like grounding) was very important with that version of 
ethernet hardware.


It's my understanding that the marks (black bands or other markings on 
the sheath) were exactly one wavelength apart.  Which from what I 
remember ~> understand from my ham radio days is quite important.




--
Grant. . . .
unix || die

Re: Ethernet cable (Was: Sun3 valuations?)

[Bill Gunshannon via cctalk]

Vampire taps.  Now there's a blast from the past.  Somewhere around here
I still have my toolbag which still has my tap drill for installing those taps.

bill


From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Al Kossow via cctalk 
<cctalk@classiccmp.org>
Sent: Tuesday, January 23, 2018 11:10 AM
To: cctalk@classiccmp.org
Subject: Re: Ethernet cable (Was: Sun3 valuations?)

there are pictures of the transceiver w/o the vampire tap on bitsavers
under http://bitsavers.org/pdf/xerox/ethernet_3mb/

On 1/23/18 7:51 AM, Noel Chiappa via cctalk wrote:
> > From: Grant Taylor
>
> > According to the following page, it was not RG-8 cable ... As such it
> > was purpose built.
>
> The 10MBit cable, yes; it was custom (you can see 'Ethernet' printed on the
> chunk in the picture). (I'd forgotten about the black stripes! I'm not sure
> we really bothered to follow that.)
>
> The earlier 3Mbit I'm not so sure about - that has the air of standard
> commercial coax.
>
> I wish there was a picture of a 3Mbit transceiver, clamp-on holder, etc! Does
> the CHM or LCM have them with their Alto stuff?
>
>Noel
>

Re: Ethernet cable (Was: Sun3 valuations?)

[Bill Gunshannon via cctalk]

If you didn't locate the transceivers on those black marks you would
have had terrible performance as that affects collisions.  Timing (among
other things like grounding) was very important with that version of
ethernet hardware.

bill


From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Noel Chiappa via 
cctalk <cctalk@classiccmp.org>
Sent: Tuesday, January 23, 2018 10:51 AM
To: cctalk@classiccmp.org
Cc: j...@mercury.lcs.mit.edu
Subject: Re: Ethernet cable (Was: Sun3 valuations?)

> From: Grant Taylor

> According to the following page, it was not RG-8 cable ... As such it
> was purpose built.

The 10MBit cable, yes; it was custom (you can see 'Ethernet' printed on the
chunk in the picture). (I'd forgotten about the black stripes! I'm not sure
we really bothered to follow that.)

The earlier 3Mbit I'm not so sure about - that has the air of standard
commercial coax.

I wish there was a picture of a 3Mbit transceiver, clamp-on holder, etc! Does
the CHM or LCM have them with their Alto stuff?

Noel

Re: Ethernet cable (Was: Sun3 valuations?)

[Al Kossow via cctalk]

there are pictures of the transceiver w/o the vampire tap on bitsavers
under http://bitsavers.org/pdf/xerox/ethernet_3mb/

On 1/23/18 7:51 AM, Noel Chiappa via cctalk wrote:
> > From: Grant Taylor
> 
> > According to the following page, it was not RG-8 cable ... As such it
> > was purpose built.
> 
> The 10MBit cable, yes; it was custom (you can see 'Ethernet' printed on the
> chunk in the picture). (I'd forgotten about the black stripes! I'm not sure
> we really bothered to follow that.)
> 
> The earlier 3Mbit I'm not so sure about - that has the air of standard
> commercial coax.
> 
> I wish there was a picture of a 3Mbit transceiver, clamp-on holder, etc! Does
> the CHM or LCM have them with their Alto stuff?
> 
>   Noel
> 

Re: Ethernet cable (Was: Sun3 valuations?)

[Noel Chiappa via cctalk]

> From: Grant Taylor

> According to the following page, it was not RG-8 cable ... As such it
> was purpose built.

The 10MBit cable, yes; it was custom (you can see 'Ethernet' printed on the
chunk in the picture). (I'd forgotten about the black stripes! I'm not sure
we really bothered to follow that.)

The earlier 3Mbit I'm not so sure about - that has the air of standard
commercial coax.

I wish there was a picture of a 3Mbit transceiver, clamp-on holder, etc! Does
the CHM or LCM have them with their Alto stuff?

Noel

Re: Sun3 valuations?

[Christian Corti via cctalk]

On Mon, 22 Jan 2018, Al Kossow wrote:
Not that anyone seems to collect printers, but the LBP1 and the Canon 
engine were some of the first 'inexpensive mass-produced' laser 
printers.


I still have the Kyocera F-1010 that my father bought 30 years ago. It 
still works well, but the foam strips found in the drum unit and toner 
cartridge are troublesome. They disintegrate, with the result that toner 
is spread inside the printer...


Christian

Re: Sun3 valuations?

[jim stephens via cctalk]

On 1/22/2018 7:07 PM, Al Kossow via cctalk wrote:


On 1/22/18 5:24 PM, jim stephens via cctalk wrote:

Worth noting my 3/260 has a monochrome graphics port

x/2x0 CPUs produce 1600 x 1280, ECL 200 MHz dot clock video.

CRTs for them are pretty much impossible to find.

I have the originals, hopefully they can be made to work.

Re: Sun3 valuations?

[Al Kossow via cctalk]

On 1/22/18 5:24 PM, jim stephens via cctalk wrote:
> 

> Worth noting my 3/260 has a monochrome graphics port

x/2x0 CPUs produce 1600 x 1280, ECL 200 MHz dot clock video.

CRTs for them are pretty much impossible to find.

RE: CX laser printers (Was: Sun3 valuations?

[Fred Cisin via cctalk]

BTW, for yellowed plastic, Printerworks suggests
Sherman Williams poly-urethane paint, color S63EXH4300


On Mon, 22 Jan 2018, Ali via cctalk wrote:

Fred is this the off white color of HP printers?


At least close.
It's what Printerworks says that they use to repaint the Fedex purple 
printers back to look like the other CX based printers.   Check the 
details in the link on their site about how they convert the Fedex ones.

http://www.printerworks.com/Catalogs/CX-Catalog/CX-Fed-Ex.html
I assume that their goal is not necessarily to make them pass as HP, but 
to be close enough to look OK.

RE: CX laser printers (Was: Sun3 valuations?

[Ali via cctalk]

> BTW, for yellowed plastic, Printerworks suggests
> Sherman Williams poly-urethane paint, color S63EXH4300


Fred is this the off white color of HP printers?

-Ali

Re: Sun3 valuations?

[Pete Lancashire via cctalk]

Value . If it was in/near where I live a 3/50 with a good display would be
 oh $100. Finding a monochrome jug would be the biggest issue.

-pete

On Mon, Jan 22, 2018 at 5:24 PM, jim stephens via cctalk <
cctalk@classiccmp.org> wrote:

>
>
> On 1/22/2018 3:32 PM, Grant Taylor via cctalk wrote:
>
>> On 01/22/2018 04:06 PM, Noel Chiappa via cctalk wrote:
>>
>>> So did we ever get an answer to the original question (the value of a
>>> Sun3)? All I saw was 'you'd have to pay to recycle them'.
>>>
>>
>> I've not seen an answer to that question.  I have seen multiple people
>> raise their virtual hand in interest.  But no discussions of $ other than
>> disposal fees.
>>
> I did mention mine came free.  I also did sell my systems in the late 80s
> for some amount.  I think the answer will be relative to who is collecting
> them and their budget.  At least on this list that didn't seem to be many..
>
> As I said I'd be glad to help you make yours have value if you want my
> system, or the tapes.
>
> Al said he was open to offers for his system, which, by the way sounds
> like the 4/xxx system I had. A historical note on my system, might have
> been true of Al's depending on history too, Hamilton pre merger had a group
> which bought some of these systems, which were in my case in a 6' cabinet
> similar to the Dec H960 in size, and used them as systems for doing pal and
> other utility work.
>
> At out local Hamilton office in Orange County, where mine came from, they
> would let people come in and get accounts and use them for whatever they
> needed, usually by convincing the two local guys that you had something
> that would result in Hamilton selling some product.
>
> As to value, I'd say with the tape, my system should be worth a couple
> hundred.  No disks, but should have SCSI controller.  The tapes being the
> thing adding value.  That is with it in the state of a project machine.
> Add in the monitors and have it restored, I'd say 1000 to 1500 would be a
> reasonable asking price.
>
> Worth noting my 3/260 has a monochrome graphics port, so one would have a
> very large and power hungry Sunos 3 or Sunos 4 graphics station.  I think I
> have the Hitachi monitors that went with the system.
>
> Thanks
> Jim
>
>

Re: Sun3 valuations?

[jim stephens via cctalk]

On 1/22/2018 3:32 PM, Grant Taylor via cctalk wrote:

On 01/22/2018 04:06 PM, Noel Chiappa via cctalk wrote:
So did we ever get an answer to the original question (the value of a 
Sun3)? All I saw was 'you'd have to pay to recycle them'.


I've not seen an answer to that question.  I have seen multiple people 
raise their virtual hand in interest.  But no discussions of $ other 
than disposal fees. 
I did mention mine came free.  I also did sell my systems in the late 
80s for some amount.  I think the answer will be relative to who is 
collecting them and their budget.  At least on this list that didn't 
seem to be many..


As I said I'd be glad to help you make yours have value if you want my 
system, or the tapes.


Al said he was open to offers for his system, which, by the way sounds 
like the 4/xxx system I had. A historical note on my system, might have 
been true of Al's depending on history too, Hamilton pre merger had a 
group which bought some of these systems, which were in my case in a 6' 
cabinet similar to the Dec H960 in size, and used them as systems for 
doing pal and other utility work.


At out local Hamilton office in Orange County, where mine came from, 
they would let people come in and get accounts and use them for whatever 
they needed, usually by convincing the two local guys that you had 
something that would result in Hamilton selling some product.


As to value, I'd say with the tape, my system should be worth a couple 
hundred.  No disks, but should have SCSI controller.  The tapes being 
the thing adding value.  That is with it in the state of a project 
machine.  Add in the monitors and have it restored, I'd say 1000 to 1500 
would be a reasonable asking price.


Worth noting my 3/260 has a monochrome graphics port, so one would have 
a very large and power hungry Sunos 3 or Sunos 4 graphics station.  I 
think I have the Hitachi monitors that went with the system.


Thanks
Jim

Re: Sun3 valuations?

[Guy Sotomayor Jr via cctalk]

> On Jan 22, 2018, at 5:03 PM, Noel Chiappa via cctalk  
> wrote:
> 
> 
>> From: Guy Sotomayor Jr
> 
>> The XGP printed on roll paper. It was a laser type process
> 
> Plain paper? Well, my memory of it being thermal paper could easily be wrong;
> it's been a _long_ time, and I didn't use it much.
> 

It’s been longer for me!  ;-)

But I *did* use it *a lot* when I was there.

Missed using it until one of my co-workers at IBM started “playing” with an IBM 
4250
electro-erosion printer (I believe it was 600dpi H and 600dpi V).  It used 
aluminized
mylar (rolls again) — hence the electro erosion.  He wrote a bunch of SW for it 
and
ran it off of his PC-AT (at the time) and could produce “camera ready” results. 
 You
could also do limited print runs (100-500 copies) directly from resultant 
mylar.  Very
cool device…not really fast though.

TTFN - Guy

Re: Sun3 valuations?

[Noel Chiappa via cctalk]

> I just found a piece, I'll put up a photo.

Here ya go:

  http://gunkies.org/wiki/File:3MegEthernetCable.jpg
  http://gunkies.org/wiki/File:10MegEthernetCable.jpg

I should have put a ruler in, for scale. The 3M is about 2/3 of the thickness
of the 10M. The center conductor is about 2mm - pretty heavy!


> From: Guy Sotomayor Jr

> The XGP printed on roll paper. It was a laser type process

Plain paper? Well, my memory of it being thermal paper could easily be wrong;
it's been a _long_ time, and I didn't use it much.

 Noel

Re: Sun3 valuations?

[Guy Sotomayor Jr via cctalk]

> On Jan 22, 2018, at 4:08 PM, Noel Chiappa via cctalk  
> wrote:
> 
>> From: Grant Taylor
> 
>> What makes the copies of papers printed on them special?
> 
> Well, the Dover was the first device (that I know of) that could print _very_
> high-quality graphical/multi-font output, and on ordinary paper. It was also
> pretty darned fast - a couple of seconds per sheet, IIRC. The whole package
> just blew us all away (I was a MIT when we got ours).
> 
> There was a prior device (from quite a few years before) called a 'Xerox
> Graphics Printer', but i) IIRC it printed on thermal paper (think
> poor-quality thermal fax paper); ii) the resolution was nothing like as high
> as that of the Dover (which was, IIRC, in the 100's of DPIs - which it needed
> to produce the very-high quality printout with type-faces), and iii) it was
> quite slow.

The XGP printed on roll paper.  It was a laser type process and used a modified
Xerox copy engine.  It had a cutter to cut the roll paper to size (computer 
controlled
natch).  The cutter caused *no* end of troubles.

AFAIR it wasn’t particularly slow given the output quality.  Ours at CMU was
driven by an 11/45.  All of the CMU docs produced by the CS department were
printed by the XGP (and typeset by Scribe).  I still have various docs 
(including
my copy of the Hydra Songbook) and they look quite good.

TTFN - Guy

Re: Sun3 valuations?

[Noel Chiappa via cctalk]

> From: Grant Taylor

> What makes the copies of papers printed on them special?

Well, the Dover was the first device (that I know of) that could print _very_
high-quality graphical/multi-font output, and on ordinary paper. It was also
pretty darned fast - a couple of seconds per sheet, IIRC. The whole package
just blew us all away (I was a MIT when we got ours).

There was a prior device (from quite a few years before) called a 'Xerox
Graphics Printer', but i) IIRC it printed on thermal paper (think
poor-quality thermal fax paper); ii) the resolution was nothing like as high
as that of the Dover (which was, IIRC, in the 100's of DPIs - which it needed
to produce the very-high quality printout with type-faces), and iii) it was
quite slow.

What they did with the Dover was take a high-end Xerox copier (one of the
things the size of a couple of desks),and rip out the optical front end
(which copied an image of the page being copied, onto the drum), and replaced
it with a scanning laser that was fed an amplitude-controlling bit-stream
from an interface card in the Alto.


>> That's the 'original' Ethernet; PARC did the 3Mbit one first, and the
>> 10 Mbit one came along quite a few years later.

> I assume this has something to do with the Digital / Intel / Xerox as
> in the DIX connector.

Right, a couple of years later Xerox, DEC and Intel did a consortium to make
Ethernet widely available, and produced the 10Mbit version. Technically, it
was little different from the 3MBit version. The low-level packet format was
different (because of the higher speed, and larger maximum size), and the
addresses used the later PARC thinking (UID's for interfaces), but those were
not major changes.

>> I'm trying to remember what kind of cable it used

> That sounds like typical Radio Grade cable.

Yeah, I just found a piece, I'll put up a photo.

> I'm not quite sure what you mean by "solid like CATV".

The CATV that used a heavy foil ground layer.


> That sounds like a description of what I've heard called a "Vampire
> Tap". My understanding is that's the poor way to connect to (what is
> effectively) the Ethernet bus.

Vampire taps worked fine on 3MB Ethernet. As the speeds went up, less so.


> I suspect that Wikipedia's article on 10Base5 has some decent pictures:

Nothing of the 3MB, and it doesn't show how the clamp-on connector and
vampire worked.

Noel

Re: CX laser printers (Was: Sun3 valuations?

[Toby Thain via cctalk]

On 2018-01-22 6:06 PM, Steven M Jones via cctalk wrote:
> On 01/22/2018 11:14, Fred Cisin via cctalk wrote:
>>
>> For a brief while, the LaserWriter was the fastest, most powerful
>> computer in Apple's limeup.  If you are crazy enough, You can
>> communicate directly with it and program in Postscript (similar to Forth)
> 
> Heck, it was faster than the Macs, PCs, and the VAX-11/750 we had! At
> least for one storage-free job at a time.
> 
> A few of my fellow students (hello D Fischer) who fiddled with
> Postscript would download jobs to compute and print fractals that would
> run overnight on the printer... and much of the following day, in some
> cases.

Assuming you didn't fill the heap. Garbage collection wasn't implemented
during a job. :)


--T

> 
> --S.
> 
> 

Re: Sun3 valuations?

[Al Kossow via cctalk]

On 1/22/18 3:06 PM, Noel Chiappa via cctalk wrote:

> I'm trying to remember what kind of cable it used; IIRC it was black coax,
> with a woven shield (i.e. not solid like CATV), not quite as large in
> diameter as the yellow 10Mbit stuff. To connect up to it, one clamped on a
> connector thingy, which had a threaded hole in it over the cable; one then
> screwed in a cylindrical cutter which made a hole through the shield, and one
> then screwed in a transceiver (which was a box about 2"x2"x4", IIRC).
> Hopefully someone has a picture somewhere?

It's 75 ohm cable TV impedence (RG11?)

I use RG-59 and BNCs for my Alto networks at CHM.
You can pull the stingers off of the silver transceiver boxes easily and 
replace it with a
BNC female socket.

I've got a chunk of the orange plenum stuff with the vampire taps and 
terminators in storage.

Re: Sun3 valuations?

[Grant Taylor via cctalk]

On 01/22/2018 04:06 PM, Noel Chiappa via cctalk wrote:
So did we ever get an answer to the original question (the value of a 
Sun3)? All I saw was 'you'd have to pay to recycle them'.


I've not seen an answer to that question.  I have seen multiple people 
raise their virtual hand in interest.  But no discussions of $ other 
than disposal fees.


Sorry, I don't understand the question. (I assume you're not simply asking 
'what made the Dover and Altos special'.) Which context?


What makes the copies of papers printed on them special?  Was there 
something about the quality?  Or is it simply that the documents were 
printed via machines that were intriguing unto themselves.


(As in 'what's the connection between the Sun3 query, and Dovers and 
Altos'? If so, I think it was just thread drift via the laser printers.)


ACK

That's the 'original' Ethernet; PARC did the 3Mbit one first, and the 
10 Mbit one came along quite a few years later.


I assume this has something to do with the Digital / Intel / Xerox as in 
the DIX connector.


I'm trying to remember what kind of cable it used; IIRC it was black coax, 
with a woven shield (i.e. not solid like CATV), not quite as large in 
diameter as the yellow 10Mbit stuff.


That sounds like typical Radio Grade cable.  I just have no idea which 
RG it was.  I'm not quite sure what you mean by "solid like CATV".  Much 
of the coax that I've seen used for cable TV is RG-59, or RG-6.  Both of 
which ideally have a woven braid w/ 80% or greater coverage.  I have 
seen some that is effectively foil wrapped around the inner dielectric 
insulator.  I like to see solid dielectric insulators, but I have 
suffered through some that were a helical coil around a center conductor 
that may or may not have some sort of thin coating.


I have long found Radio Grade cable to be confusing (as in I've not 
figured out any pattern) as well as some of the executions to be 
extremely bad.  Usually, but not always, the more expensive it is 
(within reason) the better quality it is.  Save for the stuff that 
artificially jumps the price to catch people that shop solely based on 
price = quality.


To connect up to it, one clamped on a connector thingy, which had a 
threaded hole in it over the cable; one then screwed in a cylindrical 
cutter which made a hole through the shield, and one then screwed in a 
transceiver (which was a box about 2"x2"x4", IIRC).


That sounds like a description of what I've heard called a "Vampire 
Tap".  -  My understanding is that's the poor way to connect to (what is 
effectively) the Ethernet bus.


I've been told that it's more proper to take an outage, cut the cable, 
terminate the ends properly, and connect both ends to a new AUI (DIX?) 
breakout box.



Hopefully someone has a picture somewhere?


I suspect that Wikipedia's article on 10Base5 has some decent pictures:

Link - 10Base5
 - https://en.wikipedia.org/wiki/10BASE5

Google's image search for thicknet has a number of things too.

I never have managed to get my hands on any Thicknet 10Base5 but I'd 
like to get just enough to connect two machines.




--
Grant. . . .
unix || die

Re: Sun3 valuations?

[Noel Chiappa via cctalk]

So did we ever get an answer to the original question (the value of
a Sun3)? All I saw was 'you'd have to pay to recycle them'.


> From: Grant Taylor

>> Before that, if you were lucky enough to be at Stanford, MIT, or CMU,
>> you could use the Dover and Altos that were part of Xerox's University
>> Grant Program.

> What made the Dover and Altos special in this context?

Sorry, I don't understand the question. (I assume you're not simply asking
'what made the Dover and Altos special'.) Which context? (As in 'what's the
connection between the Sun3 query, and Dovers and Altos'? If so, I think it
was just thread drift via the laser printers.)

> This is the 2nd time I've heard about 3 Mbps Ethernet. 

That's the 'original' Ethernet; PARC did the 3Mbit one first, and the 10 Mbit
one came along quite a few years later.

I'm trying to remember what kind of cable it used; IIRC it was black coax,
with a woven shield (i.e. not solid like CATV), not quite as large in
diameter as the yellow 10Mbit stuff. To connect up to it, one clamped on a
connector thingy, which had a threaded hole in it over the cable; one then
screwed in a cylindrical cutter which made a hole through the shield, and one
then screwed in a transceiver (which was a box about 2"x2"x4", IIRC).
Hopefully someone has a picture somewhere?

Noel

Re: CX laser printers (Was: Sun3 valuations?

[Steven M Jones via cctalk]

On 01/22/2018 11:14, Fred Cisin via cctalk wrote:


For a brief while, the LaserWriter was the fastest, most powerful 
computer in Apple's limeup.  If you are crazy enough, You can 
communicate directly with it and program in Postscript (similar to Forth)


Heck, it was faster than the Macs, PCs, and the VAX-11/750 we had! At 
least for one storage-free job at a time.


A few of my fellow students (hello D Fischer) who fiddled with 
Postscript would download jobs to compute and print fractals that would 
run overnight on the printer... and much of the following day, in some 
cases.


--S.

CX laser printers (Was: Sun3 valuations?

[Fred Cisin via cctalk]

On Mon, 22 Jan 2018, Pete Lancashire via cctalk wrote:

Imagen .. yes. The printer we had was a Cannon engine, the same one HP
used. All our work was for 8-1/2"x11" and its 300DPI
was good enough for our use.
LBP8 ?


The Canon CX mechanism was used by many companies.
Some, such as Apple Laserwriter (Postscript) and HP Laserjet (PCL) used an 
added controller in the case.
For a brief while, the LaserWriter was the fastest, most powerful computer 
in Apple's limeup.  If you are crazy enough, You can communicate directly 
with it and program in Postscript (similar to Forth)


Others, such as Cordata/"Corona Data Systems" (software refuses to run on 
286 and above), Jetscript, J-laser, Eiconscript (Laserjet and Postscript 
emulation), Imagen?, ...
used a brain-dead engine, with controller in the host and connected with a 
DC-37.

http://www.printerworks.com/Catalogs/CX-Catalog/CX-VDO.html

The Printerworks CX (and for some others, their SX) catalog, if you can 
find a dead-tree copy, is an essential reference.

http://www.printerworks.com/Catalogs/CX-Catalog/CX-AssblyContents.html

Printerworks claims that their improved drum and improved toner solves the
inadequate black-fill problem that caused many to switch to SX based 
printers.



If you run into a PURPLE CX printer, that's the Fedex "Zap Mail", which is 
modified for 415spi, instead of 300

http://www.printerworks.com/Catalogs/CX-Catalog/CX-Fed-Ex.html

BTW, for yellowed plastic, Printerworks suggests
Sherman Williams poly-urethane paint, color S63EXH4300


--
Grumpy Ol' Fred ci...@xenosoft.com

Re: Sun3 valuations?

[Al Kossow via cctalk]

On 1/22/18 11:01 AM, Toby Thain via cctalk wrote:

> I still own an original Canon engine Apple Laserwriter or two.

CX engine printers (Laserjet, Laserwriter) are still out there printing.

The liquid toner beasts are the ones that have probably gone extinct

Re: Sun3 valuations?

[Toby Thain via cctalk]

On 2018-01-22 1:24 PM, Al Kossow via cctalk wrote:
> 
> 
> On 1/22/18 10:08 AM, Pete Lancashire wrote:
> 
>> BTW I had at home a LBP1 ? that came from the R Labs. Quite the beast it 
>> used a toner that was suspended in a liquid.
> 
> Not that anyone seems to collect printers, but the LBP1 and the Canon engine 
> were some of the
> first 'inexpensive mass-produced' laser printers.
> 
> I don't know of any that still survive.

I still own an original Canon engine Apple Laserwriter or two. (Or at
worst, LW Plus.. don't remember exactly).

--Toby


> 
> Before that, if you were lucky enough to be at Stanford, MIT, or CMU, you 
> could use the Dover
> and Altos that were part of Xerox's University Grant Program. ...
> 
> 

Re: Sun3 valuations?

[Grant Taylor via cctalk]

On 01/22/2018 11:24 AM, Al Kossow via cctalk wrote:
Before that, if you were lucky enough to be at Stanford, MIT, or CMU, 
you could use the Dover and Altos that were part of Xerox's University 
Grant Program. Copies of well-known papers from the early 80s are very 
distinctive because they were printed on them.


What made the Dover and Altos special in this context?

Eventually, the Dover was networked to other computers. Stanford had a 
rather big 3mbit research Ethernet made with SUN board gateways.


Intriguing.  This is the 2nd time I've heard about 3 Mbps Ethernet.  The 
first was in the series of videos that Curious Mark has shared on 
YouTube about the restoration of multiple Altos.


Not that any of this has much to do with Sun-3, other that it was possible 
to plug a SUN 3mbit ethernet board into one with a Multibus adapter. I 
had packets coming out of a Sun-3 a VERY long time ago and still have 
a bunch of the 3mbit Multibus boards.


I wonder if Curious Mark and co would be interested in possibly 
acquiring one of the 3 Mbps boards.  (Of course that would necessitate a 
Sun to put it in.)  -  I think they hacked something together, so the 
need may not be that great.




--
Grant. . . .
unix || die

Re: Sun3 valuations?

[Al Kossow via cctalk]

On 1/22/18 10:08 AM, Pete Lancashire wrote:

> BTW I had at home a LBP1 ? that came from the R Labs. Quite the beast it 
> used a toner that was suspended in a liquid.

Not that anyone seems to collect printers, but the LBP1 and the Canon engine 
were some of the
first 'inexpensive mass-produced' laser printers.

I don't know of any that still survive.

Before that, if you were lucky enough to be at Stanford, MIT, or CMU, you could 
use the Dover
and Altos that were part of Xerox's University Grant Program. Copies of 
well-known papers from the early
80s are very distinctive because they were printed on them.

Eventually, the Dover was networked to other computers. Stanford had a rather 
big 3mbit research Ethernet
made with SUN board gateways.

Not that any of this has much to do with Sun-3, other that it was possible to 
plug a SUN 3mbit ethernet
board into one with a Multibus adapter. I had packets coming out of a Sun-3 a 
VERY long time ago and
still have a bunch of the 3mbit Multibus boards.

Re: Sun3 valuations?

[Pete Lancashire via cctalk]

Imagen .. yes. The printer we had was a Cannon engine, the same one HP
used. All our work was for 8-1/2"x11" and its 300DPI
was good enough for our use.

LBP8 ?

BTW I had at home a LBP1 ? that came from the R Labs. Quite the beast it
used a toner that was suspended in a liquid.
Can one say VENTILATION required :-) I had it in the garage.

-pete



On Mon, Jan 22, 2018 at 10:00 AM, Al Kossow via cctalk <
cctalk@classiccmp.org> wrote:

>
>
> On 1/22/18 9:57 AM, Brent Hilpert via cctalk wrote:
>
> > Wasn't the internal controller the early Sun processor board (basically
> a 68000 single-board computer that preceded or was used in the Sun 1), or
> am I conflating things? (We had a Sun 1 quite early as well).
> >
>
> Imagen founded by people from Stanford. The original printer used a
> Stanford SUN board.
> Note, SUN (Stanford University Network) and not "Sun"
>
>
>
>

Re: Sun3 valuations?

[Al Kossow via cctalk]

On 1/22/18 9:57 AM, Brent Hilpert via cctalk wrote:

> Wasn't the internal controller the early Sun processor board (basically a 
> 68000 single-board computer that preceded or was used in the Sun 1), or am I 
> conflating things? (We had a Sun 1 quite early as well).
> 

Imagen founded by people from Stanford. The original printer used a Stanford 
SUN board.
Note, SUN (Stanford University Network) and not "Sun"

Re: Sun3 valuations?

[Brent Hilpert via cctalk]

On 2018-Jan-22, at 1:24 AM, Pete Lancashire via cctalk wrote:
> My interest would be from having the first Sun systems in the Portland
> Oregon area. It consisted of a 3/260 w a Fujitsu Eagle, and a 90 ips 9
> track that I cant remember the make.
> Tied to it where 3 3/50s. Initially diskless then I added a 40 MB drive to
> each of them.
> 
> Networked into the companies network, tapped into on of the yellow coaxes
> up in the ceiling.
> 
> I all was for running Interleaf. Oh yea printing was via a Imagin (sp?)
> print engine.

The early 'compact' laser printer ca. 1984 (table-top sized as opposed to the 
20sqft of floor space of the 1st gen of laser printers)?
My recollection is it was "Imagen".
I took it as incorporating "image", and "generate" or "engine" (my perception).

We had one in the CS department. Nice for the time, but required regular 
cleaning/maintenance, dept. tech guy would roll his eyes - " . . again?"

Wasn't the internal controller the early Sun processor board (basically a 68000 
single-board computer that preceded or was used in the Sun 1), or am I 
conflating things? (We had a Sun 1 quite early as well).

Re: Sun3 valuations?

[Brent Hilpert via cctalk]

On 2018-Jan-22, at 1:24 AM, Pete Lancashire via cctalk wrote:
> My interest would be from having the first Sun systems in the Portland
> Oregon area. It consisted of a 3/260 w a Fujitsu Eagle, and a 90 ips 9
> track that I cant remember the make.
> Tied to it where 3 3/50s. Initially diskless then I added a 40 MB drive to
> each of them.
> 
> Networked into the companies network, tapped into on of the yellow coaxes
> up in the ceiling.
> 
> I all was for running Interleaf. Oh yea printing was via a Imagin (sp?)
> print engine.

The early 'compact' laser printer ca. 1984 (table-top sized as opposed to the 
20sqft of floor space of the 1st gen of laser printers)?
My recollection is it was "Imagen".
I took it as incorporating "image", and "generate" or "engine" (my perception).

We had one in the CS department. Nice for the time, but required regular 
cleaning/maintenance, dept. tech guy would roll his eyes - " . . again?"

Wasn't the internal controller the early Sun processor board (basically a 68000 
single-board computer that preceded or was used in the Sun 1), or am I 
conflating things? (We had a Sun 1 quite early as well).

Re: Sun3 valuations?

[Al Kossow via cctalk]

On 1/21/18 8:53 PM, Kevin Bowling via cctalk wrote:
> Several people asked my location.. Phoenix, AZ.  Freighting stuff is
> neither hard nor expensive if it comes to that but I'm just trying to
> gauge value at the moment.
> 

I have a 3/x80 full server rack with 1/2 tape, no disks, and dozens of 9u 
boards from
3/160 up through 4/3x0 I'd like to sell in Fremont, CA if someone wants to make 
a reasonable
offer and can pick them up from there.

Re: Sun3 valuations?

[Pete Lancashire via cctalk]

My interest would be from having the first Sun systems in the Portland
Oregon area. It consisted of a 3/260 w a Fujitsu Eagle, and a 90 ips 9
track that I cant remember the make.
Tied to it where 3 3/50s. Initially diskless then I added a 40 MB drive to
each of them.

Networked into the companies network, tapped into on of the yellow coaxes
up in the ceiling.

I all was for running Interleaf. Oh yea printing was via a Imagin (sp?)
print engine.

Purpose was composing and printing component specifications at Tektronix

-pete



On Sun, Jan 21, 2018 at 11:37 PM, emanuel stiebler via cctalk <
cctalk@classiccmp.org> wrote:

> On 2018-01-21 23:47, Kevin Bowling via cctalk wrote:
> > I have some sun3/vme systems
> >
> > Several 3/60
> > 3/260
> > sparcstation 4/370
> > SMD disk array for 3/260
> >
> > The 3/260 and 4/370 have some oddball boards for data (cosys) and
> > video acquisition (Aviv).
> >
> > I also have some spare sparcstation 10s and 20s.
> >
> > I haven't seen sun3 stuff for sale much.  Does anyone know approximate
> > valuations for tested systems?
>
> Hello Kevin,
> I would be interested in all the 68000 based systems. If you like to get
> rid of them, I would give them a good home.
>
> All the best,
> emanuel
> (colorado, usa)
>
>

Re: Sun3 valuations?

[emanuel stiebler via cctalk]

On 2018-01-21 23:47, Kevin Bowling via cctalk wrote:
> I have some sun3/vme systems
> 
> Several 3/60
> 3/260
> sparcstation 4/370
> SMD disk array for 3/260
> 
> The 3/260 and 4/370 have some oddball boards for data (cosys) and
> video acquisition (Aviv).
> 
> I also have some spare sparcstation 10s and 20s.
> 
> I haven't seen sun3 stuff for sale much.  Does anyone know approximate
> valuations for tested systems?

Hello Kevin,
I would be interested in all the 68000 based systems. If you like to get
rid of them, I would give them a good home.

All the best,
emanuel
(colorado, usa)

Re: Sun3 valuations?

[Kevin Bowling via cctalk]

Several people asked my location.. Phoenix, AZ.  Freighting stuff is
neither hard nor expensive if it comes to that but I'm just trying to
gauge value at the moment.

On Sun, Jan 21, 2018 at 3:47 PM, Kevin Bowling  wrote:
> I have some sun3/vme systems
>
> Several 3/60
> 3/260
> sparcstation 4/370
> SMD disk array for 3/260
>
> The 3/260 and 4/370 have some oddball boards for data (cosys) and
> video acquisition (Aviv).
>
> I also have some spare sparcstation 10s and 20s.
>
> I haven't seen sun3 stuff for sale much.  Does anyone know approximate
> valuations for tested systems?
>
> Regards,
> Kevin

Re: Sun3 valuations?

[Bill Gunshannon via cctalk]

It's nice to see all the interest.  I gave all my Sun stuff (except one 
UltraSPARC)
to a museum several years ago and I hope they are still happily plugging away.

bill


From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Pete Lancashire via 
cctalk <cctalk@classiccmp.org>
Sent: Sunday, January 21, 2018 9:11 PM
To: Kevin Bowling; General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Sun3 valuations?

Location ?

-pete

On Sun, Jan 21, 2018 at 2:47 PM, Kevin Bowling via cctalk <
cctalk@classiccmp.org> wrote:

> I have some sun3/vme systems
>
> Several 3/60
> 3/260
> sparcstation 4/370
> SMD disk array for 3/260
>
> The 3/260 and 4/370 have some oddball boards for data (cosys) and
> video acquisition (Aviv).
>
> I also have some spare sparcstation 10s and 20s.
>
> I haven't seen sun3 stuff for sale much.  Does anyone know approximate
> valuations for tested systems?
>
> Regards,
> Kevin
>
>

Re: Sun3 valuations?

[Pete Lancashire via cctalk]

Location ?

-pete

On Sun, Jan 21, 2018 at 2:47 PM, Kevin Bowling via cctalk <
cctalk@classiccmp.org> wrote:

> I have some sun3/vme systems
>
> Several 3/60
> 3/260
> sparcstation 4/370
> SMD disk array for 3/260
>
> The 3/260 and 4/370 have some oddball boards for data (cosys) and
> video acquisition (Aviv).
>
> I also have some spare sparcstation 10s and 20s.
>
> I haven't seen sun3 stuff for sale much.  Does anyone know approximate
> valuations for tested systems?
>
> Regards,
> Kevin
>
>

Re: Sun3 valuations?

[Toby Thain via cctalk]

On 2018-01-21 5:47 PM, Kevin Bowling via cctalk wrote:
> I have some sun3/vme systems
> 
> Several 3/60
> 3/260
> sparcstation 4/370
> SMD disk array for 3/260
> 
> The 3/260 and 4/370 have some oddball boards for data (cosys) and
> video acquisition (Aviv).
> 
> I also have some spare sparcstation 10s and 20s.
> 
> I haven't seen sun3 stuff for sale much.  Does anyone know approximate
> valuations for tested systems?
> 
> Regards,
> Kevin
> 


Where are you located?

These are very nice systems, and not so easy to find any more.

--Toby

Re: Sun3 valuations?

[jim stephens via cctalk]

On 1/21/2018 2:47 PM, Kevin Bowling via cctalk wrote:

I have some sun3/vme systems

Several 3/60
3/260
sparcstation 4/370
SMD disk array for 3/260

The 3/260 and 4/370 have some oddball boards for data (cosys) and
video acquisition (Aviv).

I also have some spare sparcstation 10s and 20s.

I haven't seen sun3 stuff for sale much.  Does anyone know approximate
valuations for tested systems?

Regards,
Kevin



Kevin,
I've got a 3/260 which was formerly owned by Rockwell here in Orange 
County, CA.  I got it from storage of a friend who was reducing clutter 
at a site so can't help with valuation.


It is the deskside unit which will be the Sun VME and VME adapter card 
they used equipped.  I've not opened it, but it may be a bit rangy.


I don't have any of the disk bricks, and am hoping that some fiddling 
will allow me to run something more modern than the sun scsi bricks if I 
do run them.  Not sure what you have.  This is the deskside unit, and 
I'm not sure if they had hard drives integrated. My system uses QIC 
tapes, and I've got some tape which were in the pile, but have low 
expectations any of them are good.  Storage was not optimized, and even 
with that QIC is seldom useful at this point.  Best hope will be 
recovery if I need to to boot the system.


I thin the 4x systems were supposed to have the Sparc first run 
processor, and the 3/xxx were to have 68000.  People could mix and match 
as could Sun.  I've owned and have running but long ago sold a 4/280 and 
had a couple of 3/280s, so have some experience.


The 4/280 had Fuji SMD drives and were nice, but horrible power hogs, so 
I sold them off as they were large and I couldn't afford to run and 
maintain them.   I'm curious where you are located, as my interest in 
this project is low, and you'd be welcome to try your project with 
anything I've got if you are going to restore them.


Contact me off list if you wish to discuss more.
thanks
Jim

Re: Sun3 valuations?

[Bill Gunshannon via cctalk]

My guess is it will cost you about $25 a pop to get rid of them.  They can
not be sent to the landfill as they pre-date RoHS by quite a bit.

bill


From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Kevin Bowling via 
cctalk <cctalk@classiccmp.org>
Sent: Sunday, January 21, 2018 5:47 PM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Sun3 valuations?

I have some sun3/vme systems

Several 3/60
3/260
sparcstation 4/370
SMD disk array for 3/260

The 3/260 and 4/370 have some oddball boards for data (cosys) and
video acquisition (Aviv).

I also have some spare sparcstation 10s and 20s.

I haven't seen sun3 stuff for sale much.  Does anyone know approximate
valuations for tested systems?

Regards,
Kevin

Sun3 valuations?

[Kevin Bowling via cctalk]

I have some sun3/vme systems

Several 3/60
3/260
sparcstation 4/370
SMD disk array for 3/260

The 3/260 and 4/370 have some oddball boards for data (cosys) and
video acquisition (Aviv).

I also have some spare sparcstation 10s and 20s.

I haven't seen sun3 stuff for sale much.  Does anyone know approximate
valuations for tested systems?

Regards,
Kevin