Symmetricom S200 Teardown/upgrade to S250

[Kets_One]

To anyone needing an original Furuno GT8736, i have one laying around.
Please send me a message if you're interested.

Module is sold. Please do not message me about this anymore

[phollens]

Good Morning.  I have picked up an S250i, which I didn't notice was a model without the GPS card.  I have found some GPS cars to buy, however, I am not clear which mini RF connector is on the motherboard.  I know that the connector on the GPS card is a MMCX, but the one on the board does not look like it is the same size.  Any help would be appreciated.


 I have an X99 on the way for it.  It appears to have the same pinout as the X72.  There is an eBay auction with an ST2-Rb module with the X99, and the breakout board  says x72/X99.

I also have an X99 in my 8040C, so that should help me figure it out if it is not 100%.

Thanks for the time.

Patrick

[dj831]

Hi Patrick, perhaps the picture on previous page can help you  Two questions, though: do you still have the white cable in your S250? And second question: what GPS card did you find? That question since there's not much choices left these days ...

I too received an S250 without any options last week, but since that one is intended to be used only as an NTP server, I'm just upgrading the TXCO to an OXCO, ordered few days ago from China. Last but not least, perhaps it could be less expensive to build your own breakout board, since manufacturers like JLCPCB are very cheap 

Hope it helps.

[phollens]

There was no coax cable because the S250i doesn't have a GPS module.(That is what the 'i' at the end means)   I found an i-lotus module on AliExpress and it is on its way from China.  I have also been looking at the Hoel HD-8736 board from France.  You can find them on the on-line flea market with item number 134477429692.  I saw on some previous posts here that that card maybe didn't work as well as the i-lotus board in these systems though.

ProStudio Connection did have 2 i-lotus boards up until today.  I didn't want to pay close to  $300 for one though.

The fine people that have the HD-8736 board for sale that I referred to above let me know that the needed cable is an MCX male to MMCX male.  They gave me a samtec part number of RF174-02SP1-03RP1-0152.  Digi-key has them in stock.

I have also ordered 2 of the X72 breakout boards from South Korea, but I have not heard when they might be shipped yet. 


Patrick

[phollens]

I got the cable in from Digikey, and having to do it again I would have gone with right angle connections on both ends.  It does work, but it sets off my OCD.  The part number of the cable with both right angle connectors is RF174-02RP1-03RP1-0152.

I changed the model number to the regular S250 and I now have a GPS tab in references.  It  is giving me an open antenna warning along with a status of 'Acquiring Signal' in the GPS status tab.

I am just waiting on my PCTEL 40dB antenna and my N to BNC cable now.  I will let you know how it goes.

[phollens]

I was able to get the i-lotus GPS module installed and everything looks fine except that I still don't have GPS as an option under the Hardware Clock section.  I am thinking that it is not enough to change the model number on the S250i to get it to use the GPS time. 

Update:  I was able to get it to pick up the GPS as a HW Clock by doing a factory reset. 
Note:  You have to set everything back up from scratch.  If you restore a backup it removes GPS as a HW clock source.


Update 2:  The i-lotus board that I got from China appears to have the week number rollover bug.  It is saying that it is 2004.



Patrick

[deepskyridge]

I have a S350 that I put a i-lotus board in and it had the same problem, replaced it with one of the Heol boards from France and it is working fine for a couple of months now.

Gary

[dj831]

An update about M12 card: the HEOL card based on GT-86 is no longer available (the rebadged GT-8736 + a regulator). The good news is that they now sale a compatible card based on GT-88. That card contains a GT-88, a voltage regulator, and a serial to USB converter (CP2102 from Silabs). This time, the card is based on their own design, thus not being dependant on providers (apart Furuno with the GT-88 module). Note that firmware of the GT-88 is not standard, since by default, GT-88 uses eSip format, and not Motorola.

I had the luck to get that card, since the last GT-8736 card available on eBay was NLA - they sent me that one instead. For those who'd like to purchase one, eBay item is 134842120193. 145€ (including VAT) is not cheap, but the GT-88 from Mouser isn't either (103.80€ with VAT). And no risk about fake iLotus on AliExpress (fake, like most of ICs made from unobtainium that are curiously available on AliExpress  ).

Despite mine looks like a proto (SW jumper is not used, all three pins are soldered with a LED wire, and original choice of D2 was apparently too light), it works like a charm, either in Survey and in Dynamic mode. As a simple test, I had all LEDS green (=synced) in both modes after c.a. 14 minutes (from cold start each time).

Let's hope that helps users of fake iLotus

[nesnet]

I just received two HEOL GT-88 boards to rehab an ailing Symmetricom S200 and S300. They are plug & play... and currently I have them running into a Symmetricom antenna mounted in a closet (with no view of the sky), through a Symmetricom 1:2 splitter. They are both receiving 5-8 satellites consistently... this will improve as soon as we move them over to the outside antenna. Very sensitive receiver.

The two boards saved us a ton of money... because the manufacturer's response to mitigate the issue was "buy new time servers, they are not upgradable" -- at a total combined cost of nearly $12,000 (configured to our requirements).

Dealing with HEOL was a pleasure. I received excellent advice from a very knowledgeable individual (all through email), the boards arrived promptly in six days from order date via USPS (allowing two days for U.S. Customs processing in NY), took less than five minutes to install - and synced up quickly. We are working on another project - a Symmetricom ExactTime (ET-6000). They have a solution for that too, and the board was just shipped.

We have our Network Time Servers back at a fraction of the cost of replacing them with two new units. I didn't know HEOL existed prior to reading your post. Thanks.

[dj831]

You're welcome

Note that these devices (S200 & S300 series) ***could*** be affected by 2038 bug, AKA Y2KE38 superbug or Epochalypse (source: Wikipedia): date is coded on signed 32 bits. When clock reaches 03:14:08 UTC on 19 January 2038, there is an overflow (011111111 11111111 11111111 11111111 to 10000000 00000000 00000000 00000000), and clock displays 13 december 1901). This is a known bug of Linux, as it obviously uses Unix time representation.

I'm absolutely unsure about this, as I do not know how date is coded inside S200/300 series, but I doubt that Symmetricom wanted that their devices would last that long

Perhaps that's a thing that I could ask to EHOL, sine they knows very well these series, and have a GPS simulator.

[nesnet]

Now I have one more thing to worry about.

HEOL never disclosed a possible 2038 bug that would impact my equipment. So let me understand, in 14 years from now, I'll have to purchase another board from them? Outrageous. They should have disclosed this theoretical failure prior to the sale. I think I should withdraw my strong endorsement of their product. This GT-88 upgrade board is going to fail in 5,330 days?

I'm going to be very annoyed on January 19, 2038... when I demand a full refund or replacement board.

Thanks again, for the heads up on this egregious oversight.

Seriously, I hope the word gets out about their products. They do a great job, and I'll wager that a lot of people could save a collective truckload of money upgrading their Symmetricom (Microsemi) boat anchors.

I wonder how other vendors are handling this? I know it's not a great sales tactic, but disclosure that an upgrade path exists would have been appreciated and helpful. Imagine companies or government agencies with 20+ time servers being told to scrap them and start over. I do know that EndRun Technologies provides an upgrade service for their GPS-based products. We had two Meridian units factory upgraded.

[dj831]

Hi, no, this is NOT your EHOL card that may fail in 2038 - yours shoud last 'till c.a. 2044, i.e. rollover issue common to all GPS - but your S200/S300, due to the way it was programmed (Unix time). That being said, EHOL is one of the too few manufacturers that offers a reliable fix to GPS bug: redesign of the M12 board. Furthermore, they are fully able to fix their GT88 firmware, since they built it (unlike Furuno GT-8736)

There are Linux genious in that forum that own S200/S300 too, let's hope that at least one may answer that question. Meanwhile, I'm gonna ask O. Descoubes (EHOL) if he did the test with his GPS simulator.

---------

Edit: sorry, I missed your humour - a problem when you're not a native English or American  . But seriously, I still ask O. Descoubes and I let you know. And true, they do a tremendous job!

[nesnet]

Olivier is the person I communicated with (and is also solving my Symmetricom ExactTime ET-6000 problem). Very knowledgeable individual, who answers email in real-time. Does he sleep? I'm in NY, sending him questions at 5:30p and he answers. Isn't it 11:30p there?

Or is Olivier an AI bot?

[dj831]

Hi again, I've just asked him the question. And I asked him too if it is possible to change time system to another one (Galileo for example). And no, it's 19:23 here (GPS CET time )

[nesnet]

We have a Symmetricom S300 with Amazon Alexa built-in (it's a $2000 factory option). When I asked it for the time in Paris, it gave me the wrong answer. Maybe it's the new board.

Does anyone know what the latest software build is for the S300? I contacted Symmetricom a/k/a Microsemi and no one ever got back to me (what a surprise). It is currently at 2.80.1

Incidentally, I have a rant about your country. The last time I was in Paris (July 25, 2019) it was 107 degrees F (41.6 C) with at least 150% humidity. All the major roads were barricaded because the Tour de France was arriving the following day, and your President was attending. Military personnel on every corner. Not very tourist friendly. Spent three glorious weeks in your country that year, return every couple of years.

[dj831]

Hi, glad that you liked France But what often foreign people say about our country is that France is lovely ... apart French people (Yes, we could be much more friendly with tourists and foreign people . Sadly, it is much worse in Southern France - and not only with foreign people

About software for the S300, version 2.83 was uploaded to Google drive (user TheWizard). I cannot hely you further, since I own an S200 (OXCO upgraded) and an S250 (Rubidium factory installed).

Bonne journée !

[dj831]

Hi Nesnet, I confirm: Olivier is NOT an AI bot, he gave me a 'real' answer He (the HEOL team) tested their own servers only, and not the S200/300 series. That being said, if I had to purchase an NTP / GPS time server, I would probably purchase it from HEOL, just because they offer a real support unlike some companies (any resemblance is purely coincidental  ).

Interestingly, he sent me the Furuno GT-88 specifications protocols: the eSIP, of course, but also the M12 that I was not able to find on Furuno' site (or I was too tired/lazy/whatever else to be able to find it). I may be able to test some day the Galileo reception of the GT-88 or whatever that does not have a 10 bit week date coding, i.e. whatever else than GPS protocol.

Hence my question: is there someone browsing that topic owning a GPS simulator would be kind enough to test an S200 or S300 beyond january 2038?

Thanks! 

[nesnet]

How do I access 2.83 on his Google drive? I appreciate the information about the update availability. Thanks.

If it is confidential, pls PM me.

[nesnet]

I have heard, for years, that the French had no use for tourists... particularly Americans... an attitude I have never encountered on many business trips -- and a few vacations. It all depends on how you interact with people, IMO.

I can tell you that it's easier to communicate with French citizens than it is to get information from the U.S.-based micro semi company that manufactures network time servers. If you're fortunate enough to get a human to respond, it usually results in why they can't help you, or that the minimum factory charge is $1,000 [USD] for anything... and that you need to submit answers to about a hundred questions to use their website... ultimately to be turned down.

I was, formerly, a big supporter of their products -- and encouraged a number of colleagues to purchase them. That ship has sailed.

[dj831]

Hi, really sad to see that such big companies are so proud not to condescent to 'loose their time' to speak to individuals. Despicable attitude, IMHO.

Anyway, we are lucky enough that Eevblog exists, a place where information is not kept private and hidden from 'allmighy gods' in these companies And since data is shared by everyone to everyone, here's the link from previous page: https://drive.google.com/drive/folders/1fY7BdK7xM6wBncqCQfSFv5qZsb5m014i. The file was not shared by me, but by TheWizard (credits to him).

Hope it helps

[nesnet]

Thanks.

Just received two Symmetricom XLi SAASM (Govt spec'd) anti-jam GPS receivers. Haven't had a chance to evaluate them yet. Information is not forthcoming from the manufacturer, and very little data is publicly available. More to follow when I dig into them.

They were likely very expensive when new. It's a XLi on steroids. Complete with HTTP screens that are marked in red "Official Use Only".

If anyone can provide information, it would be appreciated.

[testpoint1]

I have the Force 22E, there is no week rollover problem for it, you just test it if exists the problem, others no need to care, it is not for Civilian use.

[JoeFloyd]

If anyone is looking for a reasonably price active L1/L2 GPS antenna, this E-Bay listing has such an antenna listed for a reasonable price.  (< $30US)   The Antenna is an Antcom 1g1215a-xsc-1-pc-RoHS-G which says that it is tolerant of LNA voltages from 2.5v to 24v.

https://datasheet.datasheetarchive.com/originals/crawler/antcom.com/9ec044cf132c90fd9bd7bbcf3b40c318.pdf

This antenna has a female SMA connector.

https://www.ebay.com/itm/324689951643

This is not my listing so buy at your own risk.

[DavidKo]

Some experience from my side. The device I have bought was without CF card. I can confirm, that no-DMA card is necessary. But double check the datasheet. Mine from Mouser Apacer *-NRG was according to description non-DMA which is not true. It need to be *NDNR* - but I cannot confirm that it will work. Other option is Delkin CE51TQMF3-F1000-D, today 9pcs available only in Newark US shop ~USD28, but their EU price 109EUR is a bad joke (F1 should be for non-removable, non DMA - datasheet available at Digikey). So I have kept searching and found Delkin CFX01GE8D1-DAAEG00 on ebay - I checked the photos of Delkin cards  and found one that seem to be OK, no remarks in description. I can confirm that this 1GB type works(datasheet).

I have replaced original GPS with HEOL. The antenna I have bought from Ali.

I want to try add OCXO, but I was not able to find Vectron MC597X4-040W. Do someone have the datasheet for Vectron or experience with different OCXO type? The pin layout seem to be common type, so different manufacturer OCXO can be used.

[tverbeure]

I was able to buy a pristine S200 at the local flea market and I'm trying to do all the upgrades that have been described here.

It came with the 1.26 software version, and it uses an AMD Geode processor board.

The Good:

• Making a copy of the 512MB flash card to a $14 white label 512MB "Industrial" flash card from Amazon was not an issue at all. I bought this one: https://www.amazon.com/dp/B07HL5F1VX
• It was also no issue to install version 1.36. Many here in this thread mention that v1.36 requires a special sized flash card that's a little bit larger than 512MB. For some reason, that's not the case for me.
• I was able to get root ssh access using the instructions earlier in this thread.
• The GPS sees either 9 or 10 satellites.

The Bad:

• The unit comes with a GT-8031H GPS module, so it has the rollover bug problem.
• It took ages to get GPS to work. There might be some bad contact somewhere? It's working fine now, but before it did, I get "Timing GPS Source" alarms, which pretty mean that the GPS module wasn't working at all.
• It never goes into "Status: Locked" state.

What I did different: I used Linux instead of Windows to do all operations. No need for HDD Raw Copy, I just used "dd" to archive the flash card file system. Also, when I plug in the flash drive in my Linux machine, I can access the file system as if it's native. It looks like this at the root:

tom@zen:/media/tom$ ll
total 13
drwxr-x---+  7 root root 4096 Mar 17 11:57 ./
drwxr-xr-x   3 root root 4096 Jul 14  2021 ../
drwxr-xr-x   4 root root 1024 Dec  8  2010 _boot/
drwxr-xr-x  18 root root 1024 Dec  8  2010 _fsroot1/
drwxr-xr-x  18 root root 1024 Dec  8  2010 _fsroot2/
drwxr-xr-x   2 root root 1024 Jan  2  2006 _persist/
drwxr-xr-x   2   99  503 1024 Jan  2  2006 _tmparea/

And when I do "sudo du -m -s" there, I get this:

tom@zen:/media/tom$ sudo du -m -s .
[sudo] password for tom:
140   .

So the flash drive contains 140MB. Again, I don't understand where that 512MB-is-not-enough issue was coming from?
One thing I did notice: when you upload the wrong file to upgrade (e.g. when uploading the .zip file instead of the .tar file), then that file won't get deleted. You can either delete it through the web interface, or, when logged in as root, by deleting all the files in "/mnt/upgrade".

Going to the biggest issue: the status remains in "unlocked mode". Any idea why that's might happen? How long does one typically need to wait until you're getting into locked mode? My TM4313 GPSDO goes into "track" mode after a few minutes. Maybe this thing needs a much longer time?

I'm using a Symmetricom 150-615 down/up converter (https://www.microsemi.com/existing-parts/parts/138272#overview), but I don't think that should matter.

Attached are some status screens...