Linux-DecNet and a DEC Terminal Server model DECServer 90L+
Hello! Since this evening was a "slow day for work" I decided to see if I could get that thing to talk to my Linux system running LAT 1.25 (from the Linux-DECNET series) via a 10BASE-T Hub that Jeff J had for sale at one of the earlier shows. Suffice to say using various incantions of tcpdump I can see the service at work and the terminal server attempting to connect. However..... that's as far as it gets. The problem is that this terminal server wears a COAX connector, and the only thing I have here (now) is that hub. Does anyone on the list have a suggestion for properly translating one format of Ethernet (COAX) to 10BBASE-T other than a Hub of unknown pedigree? ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again."
What you're looking for is a 10base2 to 10baseT adapter. Don't search for coax adapters you'll just get video dongles. Some of us have these lying around but you can quickly buy one online. Example... https://amzn.to/3SxWM51 Good luck! On Mon, Oct 24, 2022, 11:31 PM Gregg Levine via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
Hello! Since this evening was a "slow day for work" I decided to see if I could get that thing to talk to my Linux system running LAT 1.25 (from the Linux-DECNET series) via a 10BASE-T Hub that Jeff J had for sale at one of the earlier shows. Suffice to say using various incantions of tcpdump I can see the service at work and the terminal server attempting to connect. However..... that's as far as it gets.
The problem is that this terminal server wears a COAX connector, and the only thing I have here (now) is that hub. Does anyone on the list have a suggestion for properly translating one format of Ethernet (COAX) to 10BBASE-T other than a Hub of unknown pedigree? ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again."
The easy solution is to get a 10BASE-T hub that also has 10BASE-2. This is my favorite: https://www.ebay.com/itm/364020910836 You also get AUI if you want to connect to something else (thicknet, FIORL/10BASE-FL, etc.). There's no power brick to lose, and it's auto-sensing for input voltage. There are various media converters, but beware, some don't talk to modern/less old switches as they don't auto-negotiate half duplex properly. Thanks, Jonathan ------- Original Message ------- On Monday, October 24th, 2022 at 23:47, Dave Shevett via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
What you're looking for is a 10base2 to 10baseT adapter. Don't search for coax adapters you'll just get video dongles.
Some of us have these lying around but you can quickly buy one online.
Example...
Good luck!
On Mon, Oct 24, 2022, 11:31 PM Gregg Levine via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
Hello! Since this evening was a "slow day for work" I decided to see if I could get that thing to talk to my Linux system running LAT 1.25 (from the Linux-DECNET series) via a 10BASE-T Hub that Jeff J had for sale at one of the earlier shows. Suffice to say using various incantions of tcpdump I can see the service at work and the terminal server attempting to connect. However..... that's as far as it gets.
The problem is that this terminal server wears a COAX connector, and the only thing I have here (now) is that hub. Does anyone on the list have a suggestion for properly translating one format of Ethernet (COAX) to 10BBASE-T other than a Hub of unknown pedigree? ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again."
And don't forget to terminate the coax properly and use the correct impedance coax. ________________________________ From: vcf-midatlantic <vcf-midatlantic-bounces@lists.vcfed.org> on behalf of Jonathan Chapman via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> Sent: Tuesday, October 25, 2022 8:48 AM To: vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> Cc: Jonathan Chapman <lists@glitchwrks.com> Subject: Re: [vcf-midatlantic] Linux-DecNet and a DEC Terminal Server model DECServer 90L+ The easy solution is to get a 10BASE-T hub that also has 10BASE-2. This is my favorite: https://www.ebay.com/itm/364020910836 You also get AUI if you want to connect to something else (thicknet, FIORL/10BASE-FL, etc.). There's no power brick to lose, and it's auto-sensing for input voltage. There are various media converters, but beware, some don't talk to modern/less old switches as they don't auto-negotiate half duplex properly. Thanks, Jonathan ------- Original Message ------- On Monday, October 24th, 2022 at 23:47, Dave Shevett via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
What you're looking for is a 10base2 to 10baseT adapter. Don't search for coax adapters you'll just get video dongles.
Some of us have these lying around but you can quickly buy one online.
Example...
Good luck!
On Mon, Oct 24, 2022, 11:31 PM Gregg Levine via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
Hello! Since this evening was a "slow day for work" I decided to see if I could get that thing to talk to my Linux system running LAT 1.25 (from the Linux-DECNET series) via a 10BASE-T Hub that Jeff J had for sale at one of the earlier shows. Suffice to say using various incantions of tcpdump I can see the service at work and the terminal server attempting to connect. However..... that's as far as it gets.
The problem is that this terminal server wears a COAX connector, and the only thing I have here (now) is that hub. Does anyone on the list have a suggestion for properly translating one format of Ethernet (COAX) to 10BBASE-T other than a Hub of unknown pedigree? ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again."
And don't forget to terminate the coax properly and use the correct impedance coax.
Indeed! Another nice feature of that Allied Telesyn hub (and many of their devices with 10BASE-2): there's a built-in switchable 50R terminator!
You wouldn't believe the grief I had back when I was just learning about networking. I've learned a lot by trial and error. Kelly
Hello! I imagine so, except I don't do Ebay. If anyone is curious I can get a photo posted to Google Drive sometime today of the one I bought. ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again." On Tue, Oct 25, 2022 at 10:04 AM Jonathan Chapman via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
And don't forget to terminate the coax properly and use the correct impedance coax.
Indeed! Another nice feature of that Allied Telesyn hub (and many of their devices with 10BASE-2): there's a built-in switchable 50R terminator!
Thanks, Jonathan
Hello! Terminate yes, I have matching ones connected. However the impedance is one issue for this Terminal Server, I am not sure about. ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again." On Tue, Oct 25, 2022 at 9:25 AM Kelly Leavitt via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
And don't forget to terminate the coax properly and use the correct impedance coax.
________________________________ From: vcf-midatlantic <vcf-midatlantic-bounces@lists.vcfed.org> on behalf of Jonathan Chapman via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> Sent: Tuesday, October 25, 2022 8:48 AM To: vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> Cc: Jonathan Chapman <lists@glitchwrks.com> Subject: Re: [vcf-midatlantic] Linux-DecNet and a DEC Terminal Server model DECServer 90L+
The easy solution is to get a 10BASE-T hub that also has 10BASE-2. This is my favorite:
https://www.ebay.com/itm/364020910836
You also get AUI if you want to connect to something else (thicknet, FIORL/10BASE-FL, etc.). There's no power brick to lose, and it's auto-sensing for input voltage.
There are various media converters, but beware, some don't talk to modern/less old switches as they don't auto-negotiate half duplex properly.
Thanks, Jonathan
------- Original Message ------- On Monday, October 24th, 2022 at 23:47, Dave Shevett via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
What you're looking for is a 10base2 to 10baseT adapter. Don't search for coax adapters you'll just get video dongles.
Some of us have these lying around but you can quickly buy one online.
Example...
Good luck!
On Mon, Oct 24, 2022, 11:31 PM Gregg Levine via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
Hello! Since this evening was a "slow day for work" I decided to see if I could get that thing to talk to my Linux system running LAT 1.25 (from the Linux-DECNET series) via a 10BASE-T Hub that Jeff J had for sale at one of the earlier shows. Suffice to say using various incantions of tcpdump I can see the service at work and the terminal server attempting to connect. However..... that's as far as it gets.
The problem is that this terminal server wears a COAX connector, and the only thing I have here (now) is that hub. Does anyone on the list have a suggestion for properly translating one format of Ethernet (COAX) to 10BBASE-T other than a Hub of unknown pedigree? ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again."
For such a short run (a few feet - i believe min is 3ft) the impedance isn't that important, you should be fine. But, use T connectors and terminating resistors (see https://en.wikipedia.org/wiki/10BASE2 for deets) on both ends of hte cable. You can just solder up a 50ohm resister on a BNC connector. I really loved working with 10base2 back in the day - got good at stripping and crimping BNC connectors on the fly. Sorta miss it :) On Tue, Oct 25, 2022 at 10:06 AM Gregg Levine via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
Hello! Terminate yes, I have matching ones connected. However the impedance is one issue for this Terminal Server, I am not sure about. ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again."
On Tue, Oct 25, 2022 at 9:25 AM Kelly Leavitt via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
And don't forget to terminate the coax properly and use the correct
impedance coax.
________________________________ From: vcf-midatlantic <vcf-midatlantic-bounces@lists.vcfed.org> on
behalf of Jonathan Chapman via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org>
Sent: Tuesday, October 25, 2022 8:48 AM To: vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> Cc: Jonathan Chapman <lists@glitchwrks.com> Subject: Re: [vcf-midatlantic] Linux-DecNet and a DEC Terminal Server model DECServer 90L+
The easy solution is to get a 10BASE-T hub that also has 10BASE-2. This is my favorite:
https://www.ebay.com/itm/364020910836
You also get AUI if you want to connect to something else (thicknet, FIORL/10BASE-FL, etc.). There's no power brick to lose, and it's auto-sensing for input voltage.
There are various media converters, but beware, some don't talk to modern/less old switches as they don't auto-negotiate half duplex properly.
Thanks, Jonathan
------- Original Message ------- On Monday, October 24th, 2022 at 23:47, Dave Shevett via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
What you're looking for is a 10base2 to 10baseT adapter. Don't search
for
coax adapters you'll just get video dongles.
Some of us have these lying around but you can quickly buy one online.
Example...
Good luck!
On Mon, Oct 24, 2022, 11:31 PM Gregg Levine via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
Hello! Since this evening was a "slow day for work" I decided to see if I could get that thing to talk to my Linux system running LAT 1.25 (from the Linux-DECNET series) via a 10BASE-T Hub that Jeff J had for sale at one of the earlier shows. Suffice to say using various incantions of tcpdump I can see the service at work and the terminal server attempting to connect. However..... that's as far as it gets.
The problem is that this terminal server wears a COAX connector, and the only thing I have here (now) is that hub. Does anyone on the list have a suggestion for properly translating one format of Ethernet (COAX) to 10BBASE-T other than a Hub of unknown pedigree? ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again."
-- Dave Shevett shevett@pobox.com
On 10/25/22 10:19, Dave Shevett via vcf-midatlantic wrote:
For such a short run (a few feet - i believe min is 3ft) the impedance isn't that important, you should be fine. But, use T connectors and terminating resistors (see https://en.wikipedia.org/wiki/10BASE2 for deets) on both ends of hte cable. You can just solder up a 50ohm resister on a BNC connector. I really loved working with 10base2 back in the day - got good at stripping and crimping BNC connectors on the fly. Sorta miss it :)
"Hey Bob? This ours?" -Dave -- Dave McGuire, AK4HZ New Kensington, PA
On Tue, Oct 25, 2022 at 10:33 AM Dave McGuire via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
"Hey Bob? This ours?"
This is a REALLY old joke between Dave and I when we threatened to string a length of ethernet down Rt 95 in New Jersey between our houses (about 6 miles), and having some poor public works guy pick it up next to the highway with a big ???? expression on his face. -- Dave Shevett shevett@pobox.com
On 10/25/22 10:19, Dave Shevett via vcf-midatlantic wrote:
For such a short run (a few feet - i believe min is 3ft) the impedance isn't that important, you should be fine. But, use T connectors and terminating resistors (see https://en.wikipedia.org/wiki/10BASE2 for deets) on both ends of hte cable. You can just solder up a 50ohm resister on a BNC connector. I really loved working with 10base2 back in the day - got good at stripping and crimping BNC connectors on the fly. Sorta miss it :)
How many of us still have 10Base5 splinters? ;-) I think it is okay the put one of the terminators on one side of the T, connect to the terminal server and run the other end of the cable to the T at the switch and terminate the other side of that T. I do recall that the coax had to be certain length. But I can't recall the lengths. -- Linux Home Automation Neil Cherry kd2zrq@linuxha.com http://www.linuxha.com/ Main site http://linuxha.blogspot.com/ My HA Blog Author of: Linux Smart Homes For Dummies KD2ZRQ
On 10/25/22 10:34, Neil Cherry via vcf-midatlantic wrote:
I think it is okay the put one of the terminators on one side of the T, connect to the terminal server and run the other end of the cable to the T at the switch and terminate the other side of that T.
This is perfectly fine.
I do recall that the coax had to be certain length. But I can't recall the lengths.
The minimum segment length for 10base2 is 0.5m. In 10base5 it's longer, I think 2.5m. -Dave -- Dave McGuire, AK4HZ New Kensington, PA
Hello! I just asked Google about the problems, and of course it goofed. It seems it has trouble reading its own search box sometimes. Anyway I found a dandy page here: http://retrocmp.com/how-tos/connecting-a-decserver-to-linux Of course the writer chose a different terminal server, not the one I have. But the meaning is the same here. And Dave S I have the Coax terminated with a pair of resistor ends on the T connectors. And one is wearing the same colors as the terminal server. And Dave M? This is a replicate of a problem from around 2019. ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again." On Tue, Oct 25, 2022 at 10:34 AM Neil Cherry <ncherry@linuxha.com> wrote:
On 10/25/22 10:19, Dave Shevett via vcf-midatlantic wrote:
For such a short run (a few feet - i believe min is 3ft) the impedance isn't that important, you should be fine. But, use T connectors and terminating resistors (see https://en.wikipedia.org/wiki/10BASE2 for deets) on both ends of hte cable. You can just solder up a 50ohm resister on a BNC connector. I really loved working with 10base2 back in the day - got good at stripping and crimping BNC connectors on the fly. Sorta miss it :)
How many of us still have 10Base5 splinters? ;-)
I think it is okay the put one of the terminators on one side of the T, connect to the terminal server and run the other end of the cable to the T at the switch and terminate the other side of that T.
I do recall that the coax had to be certain length. But I can't recall the lengths.
-- Linux Home Automation Neil Cherry kd2zrq@linuxha.com http://www.linuxha.com/ Main site http://linuxha.blogspot.com/ My HA Blog Author of: Linux Smart Homes For Dummies KD2ZRQ
On 10/25/22 11:21, Jonathan Chapman via vcf-midatlantic wrote:
How many of us still have 10Base5 splinters? ;-)
Thanks, Jonathan
Vampire taps! Had a co-worker who was not allowed to use Vampire taps. Every time he tried he broken the center conductor. -- Linux Home Automation Neil Cherry kd2zrq@linuxha.com http://www.linuxha.com/ Main site http://linuxha.blogspot.com/ My HA Blog Author of: Linux Smart Homes For Dummies KD2ZRQ
Can you clarify...do you need the correct connector or is this a software issue? I have bins of related hardware. Bill On Mon, Oct 24, 2022, 11:31 PM Gregg Levine via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
Hello! Since this evening was a "slow day for work" I decided to see if I could get that thing to talk to my Linux system running LAT 1.25 (from the Linux-DECNET series) via a 10BASE-T Hub that Jeff J had for sale at one of the earlier shows. Suffice to say using various incantions of tcpdump I can see the service at work and the terminal server attempting to connect. However..... that's as far as it gets.
The problem is that this terminal server wears a COAX connector, and the only thing I have here (now) is that hub. Does anyone on the list have a suggestion for properly translating one format of Ethernet (COAX) to 10BBASE-T other than a Hub of unknown pedigree? ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again."
Hello! Great question. Let's see, it's more of a hardware issue here, as the software issue seems to be working after a fashion. And in fact Dave S I just ran your idea as a search term via our friend Google, lot's of hits, but plenty of misses based pricing. Basically Bill it is indeed a hardware connection issue, to accomplish the functions of a 10base2 to 10baseT adapter. The software running on the computer is regular stock stuff from the project page. ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again." On Mon, Oct 24, 2022 at 11:52 PM Bill Degnan via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
Can you clarify...do you need the correct connector or is this a software issue? I have bins of related hardware. Bill
On Mon, Oct 24, 2022, 11:31 PM Gregg Levine via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
Hello! Since this evening was a "slow day for work" I decided to see if I could get that thing to talk to my Linux system running LAT 1.25 (from the Linux-DECNET series) via a 10BASE-T Hub that Jeff J had for sale at one of the earlier shows. Suffice to say using various incantions of tcpdump I can see the service at work and the terminal server attempting to connect. However..... that's as far as it gets.
The problem is that this terminal server wears a COAX connector, and the only thing I have here (now) is that hub. Does anyone on the list have a suggestion for properly translating one format of Ethernet (COAX) to 10BBASE-T other than a Hub of unknown pedigree? ----- Gregg C Levine gregg.drwho8@gmail.com "This signature fought the Time Wars, time and again."
On 10/24/2022 11:30 PM, Gregg Levine via vcf-midatlantic wrote:
Hello! Since this evening was a "slow day for work" I decided to see if I could get that thing to talk to my Linux system running LAT 1.25 (from the Linux-DECNET series) via a 10BASE-T Hub that Jeff J had for sale at one of the earlier shows. Suffice to say using various incantions of tcpdump I can see the service at work and the terminal server attempting to connect. However..... that's as far as it gets.
For those folks that want to crimp their own thinnet cables, There is a ratchet crimper for hex sizes .068, .100, .213, .256, .324 in the makerspace tool box. Crimps both the Pin & Ferrule
participants (8)
-
Bill Degnan -
Dave McGuire -
Dave Shevett -
Gregg Levine -
Jonathan Chapman -
Kelly Leavitt -
Martin Flynn -
Neil Cherry