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