1 - NTS 200 Time Server

Author: sgeorge, Posted on: 25 January 2016 22:19

So, what did I get? An NTS-200 time server!

It gets its UTC clock time from a GPS connection and inside basically has a stratum 1 level NTP server, internally its running VXWorks which is a Real Time OS running on an ARM cpu.

Here's a quick teardown of the innards!


This is my attempt to get a null model serial cable working (which I obviously didnt have, hence had to hack something up)

Getting the serial to work under minicom on Linux was a bit of a brain fart, I had to turn off hardware flow control and bam, it all worked.

Looking over the Symmetricom antenna that showed up, Its listed as RG59 which is 75ohm cable. Tothwolf on the Johns Arcade forum I hang out on pointed out that the NTS-200 has a plain old 50ohm BNC on the back...

Hmm Can you say 'Ohms impedence mismatch'! Very strange. The NTS-200 manual even lists RG59 specifically to be used at up to 150ft in length.

Hmmmm.. how big of a deal is this going to be? I'm not sure. Hopefully none.

Right now my biggest issue is figuring out where to run the antenna. I have a vague idea but logistically... its going to be interesting.

All my computer gear is down in the basement and 50ft of cable does not give a very long run to get out of the house, to somewhere with a clear view of the sky. Might be time to look for a longer run of cable which would suck (another expense).

Saying that, I think I can run it through the basement roof, between the walls to the outside of the lower 1/2 story (we have a split level house), which would give me SOME form of clear sky...

So, we poked the antenna outside the window and hooked it all up...

About 10 minutes of tracking satellites and its got a lock and were gold!

Except the webpages are locked out and disabled...

FTP is disabled...

Telnet is disabled...

aaaand its got an old style null modem connector, for which I have no reliable cable...

Time to get creative!

Aaaand were in!

things I learnt, if the pins on the serial are back to front the machine wont boot, it gets a serial loopback fail.

in the end I hacked up a ghetto cable

System Power On Self Test Results:
Serial Loopback Test Passed.
RAM Test Passed.
Network Interface 182-9004v8.2  (c) 1998 - 2003 Symmetricom Inc.
All Rights Reserved
Flash File System Mounted.
Source file /config/truetime.conf bytes read: 459
Time synchronization processor reset.
Download complete!

Querying for Symmetricom Device. Please wait...
Symmetricom GPS Device.
Initialization successfully completed.

I know the command to get a password reset... its just getting it input....

and were in (again)

>User name: guest
password: ********
Network Interface 182-9004v8.2  (c) 1998 - 2003 Symmetricom Inc.
All Rights Reserved
Login successful

>f100 ver
BOOTLOADER  182-9003v8.2
SOFTWARE    182-9004v8.2
FILE SYSTEM 182-9005v8.2
SER NUM     011916928A

So, we have done a password reset now we need to figure out how to unlock the console and get the server to put itself into ntp broadcast mode.

Unlocking the console requires... the front panel. Time to diagnose why the front panel is not working.

At first blush it looks like a pin has been cut but it turns out this is just a key I think, so you put the cable on the correct way.

It looks like under the rubber, the contact that connects the two wires is all gummed up or has disolved for lack of a better word.

Oh look how nasty that is!

tags: GPS, Homelab, NTP, NTS-200


Ronald said on February 16, 2020 06:37:47;

Are you still using the NTS-200 ?

We also have one of these units, but last week we faced the 'week rollover' issue on our NTS. It is now stuck in the year 2000, and we are not able to set the time manually to workaround this.

I was looking to get some sort of shell access to the NTS, which seems difficult, did you ever managed to get that via the serial console?

Our unit is in a remote location, I think I will pick it up the coming days to see if this can be fixed...

Many thanks for your response,

Stu said on February 18, 2020 22:27:38;
      yes, mine rolled about a month ago :( Nothing you can do, its a hardware problem.

check eevblog thread on nts-200 that I started in 2016 :)
B said on March 03, 2020 07:49:04;
      I had the same issue on February 18th 2020, it went back to July 17th 2000
Rhael said on August 16, 2020 19:41:25;
      Hi Guys I have a:

NTS150 BOOTLOADER 182-9023v8.2
SOFTWARE 182-9024v8.2
FILE SYSTEM 182-9041v8.2

I have a problem similar to yours as far as I can read. My NTS works well, the GPS gives me the correct location and the correct time, but the Date stayed in the year 2000, and I looked for a way to modify it but I can't do it. Do they have any news on how to solve it or simply have already been discarded.

Stu said on August 22, 2020 13:10:27;
      Hey Rhael, no news on fixing it. Its basically junk now :( which is shame.
yacine said on December 09, 2022 10:36:52;
      Hello mr Rhael

I have the same problem with NTS-150 (date stayed in the year 2003) but i don't find the solution ??
any solution you find ?


Submit A Comment

(dont include links in your comments.)