[time-nuts] KS-24361 REF-0 standalone

Bob Camp kb8tq at n1k.org
Sun Aug 9 14:21:32 EDT 2015 

Hi

And my thanks to all the others who worked on this project as well !!!

Bob

> On Aug 9, 2015, at 11:26 AM, D W <watsondaniel3 at gmail.com> wrote:
> 
> A quick update for everyone. I have successfully gotten a REF-0 to run standalone. I am using an AVR, an inexpensive GPS module and very minimal circuitry. The 'NO GPS' light is off, and SatStat shows it is locked and disciplining to the 1PPS.
> 
> The stability of this needs to be assessed for a day or two. But things are looking very good.
> 
> I plan to write up a complete procedure with code and pictures. I will post that here when I am done.
> 
> Thanks for all of your help Bob, and to the others that worked on the project.
> 
> Regards
> 
> Dan
> 
>> On Aug 8, 2015, at 7:40 PM, Bob Camp <kb8tq at n1k.org> wrote:
>> 
>> Hi
>> 
>> While the newer Oncore’s are technically backwards compatible 
>> with the old units, in practice (as you have noted) that’s not a 100%
>> sort of thing. If you work with a new(er) Oncore, you would pick different
>> strings to use for this sort of thing. In order to have a “drop in” with an
>> Oncore, you do indeed need a part made before (roughly) 2001. 
>> 
>> That kicks you back to  20 year old technology (the early Oncore silicon 
>> came out in the mid 90’s) . A *lot* has happened in Moore’s Law terms since then. 
>> A lot has also happened in “aggregate volume” (what ever you want to call 
>> volume doubling) terms. Both of those things directly impact GPS receivers. 
>> Top that off with SA going away after the early Oncore came out and you 
>> have a LOT of changes. 
>> 
>> Is that all bad? Of course not. It’s what makes me focus more on the REF-0, with 
>> a modern GPS than on the REF-1 with an old Oncore. You have the high stability /
>> long loop stuff from the SA era. You have a high speed, high sensitivity GPS to
>> go with it. In many ways, that’s the best of both worlds. 
>> 
>> ============
>> 
>> Hopefully somebody will pop up and take the gear off of your hands !!
>> 
>> Bob
>> 
>>> On Aug 8, 2015, at 1:59 PM, Bill Hawkins <bill at iaxs.net> wrote:
>>> 
>>> Bob Camp has done a fine job of explaining the recent Lucent hardware.
>>> 
>>> I have two of the old pairs with Rb oscillators and poor early Oncore
>>> receivers. 
>>> Then I got a new pair with crystals and better GPS. I got the idea to
>>> use a new
>>> crystal unit to pair with an old RB unit, so I did some research on the
>>> messages
>>> required to do that.
>>> 
>>> The data was acquired with a Pico Scope set to display the bytes as
>>> ASCII
>>> characters. The displays can be saved as text files, which can be edited
>>> with
>>> explanations of the data. I have no skills with microcomputers, and
>>> after many
>>> years working with computers have no desire to acquire them.
>>> 
>>> The messages decoded easily enough with the 1996 Oncore manual. The
>>> problem
>>> with mixing old and new units is that the old Oncore had six channels
>>> while
>>> the new one has eight. The messages don't match. The only difference is
>>> two
>>> more groups of satellite data.
>>> 
>>> I have text files (MS Word 2003) with the contents of the messages.
>>> Considering
>>> the low level of interest in this subject, please write to bill at iaxs.net
>>> for 
>>> further details. If you'd like to experiment with the hardware, please
>>> make a
>>> reasonable offer for any of it. The new units have been assembled with a
>>> 28 volt
>>> 3 amp supply into a mini-rack using aluminum angle. My time lab is being
>>> downsized due to a move to senior living apartments. There's other
>>> stuff.
>>> 
>>> Bill Hawkins
>>> Bloomington, MN 55438
>>> 
>>> 
>>> -----Original Message-----
>>> From: time-nuts [mailto:time-nuts-bounces at febo.com] On Behalf Of Bob
>>> Camp
>>> Sent: Saturday, August 08, 2015 6:33 AM
>>> To: Discussion of precise time and frequency measurement
>>> Subject: Re: [time-nuts] KS-24361 REF-0 standalone
>>> 
>>> Hi
>>> 
>>> As far as I know, the Symmetricom / HP designs that were done in the SA
>>> era
>>> (this is one of them) did not use the sawtooth correction information.
>>> The signal
>>> spreading (at the time they were designed) was just to great to make it
>>> worth 
>>> playing with. I have no authoritative source for that, but it does sound
>>> reasonable. 
>>> 
>>> As with any “absolute” statement, there are sure to be exceptions 
>>> ..
>>> 
>>> ======
>>> 
>>> For the strings, you need the right status bits in the right locations.
>>> The KS
>>> does not care that it always sees the same sat’s at the same locations
>>> directly
>>> over it’s own north pole location. It just wants data in the field. 
>>> 
>>> It does care about the TRAIM status and probably a few other bits here
>>> and there.
>>> None of them appear to be hard to guess. All of the specs for the Oncore
>>> strings
>>> are something Mr Google knows a lot about. 
>>> 
>>> If you do try to synthesize *real* strings off something like a uBlox,
>>> remember that 
>>> each of these guys had a slightly different idea about when the PPS
>>> fired relative to 
>>> things like correction data and the time label on that PPS. Getting the
>>> time label wrong
>>> is pretty easy to fix. I (unfortunately) have more than ample empirical
>>> evidence of
>>> what getting the sawtooth correction off one second does. It’s far
>>> harder to track down
>>> when only looking at the “outside” of the device.
>>> 
>>> Bob
>>> 
>>>> On Aug 7, 2015, at 8:18 PM, paul swed <paulswedb at gmail.com> wrote:
>>>> 
>>>> Dan exactly my thinking.
>>>> I will guess it wants the string that says I have a 3d position lock.
>>>> Something like @@ and 30-40 characters that would be fixed.I think
>>> there is
>>>> a CRC at the end. But all of the message can be copied from a real
>>> oncore
>>>> or simply monitor what comes out of the KS GPS unit. Hard to say whats
>>>> needed but a good discussion. Be it any number of uProcs they can all
>>>> easily do a fixed string.
>>>> Regards
>>>> Paul
>>>> WB8TSL
>>>> 
>>>>> On Fri, Aug 7, 2015 at 5:13 PM, D W <watsondaniel3 at gmail.com> wrote:
>>>>> 
>>>>> Yes, I'm hoping that it just wants a dummy string to say GPS is ok,
>>> and
>>>>> doesn't actually use any information in it. If that's the case, code
>>> can be
>>>>> developed for PIC and AVR that will work for just about anyone, using
>>> a ~$1
>>>>> chip.
>>>>> 
>>>>> Even if the string does need to contain real GPS info, it should
>>> still be
>>>>> quite easy to do.
>>>>> 
>>>>> A while back I wrote some code to parse the serial string from a
>>> Jupiter-T
>>>>> and display the information on a 4 line LCD display. It worked very
>>> nicely
>>>>> but I never did anything useful with it. I think I'll take Bob's
>>> notes and
>>>>> incorporate the REF-0. That would make for a very compact setup.
>>>>> 
>>>>> Dan
>>>>> 
>>>>>> On Aug 7, 2015, at 2:06 PM, paul swed <paulswedb at gmail.com> wrote:
>>>>>> 
>>>>>> Looking forward to the notes.
>>>>>> Yes it could be fairly simple if what ref 0 wants is a string that
>>>>>> essentially says the system is fixed with 3 d accuracy. Perhaps
>>> after
>>>>> that
>>>>>> the ref 0 makes no checks other then the string keeps coming with
>>> the
>>>>>> correct quality. Not to push a particular proc but any of the low
>>> end
>>>>> ones
>>>>>> will do that stunt very easily.
>>>>>> That would be pretty sweet.
>>>>>> Paul
>>>>>> WB8TSL
>>>>>> 
>>>>>>> On Fri, Aug 7, 2015 at 10:13 AM, Bob Camp <kb8tq at n1k.org> wrote:
>>>>>>> 
>>>>>>> Hi
>>>>>>> 
>>>>>>> Ok, I will write something up and post it here. It will probably
>>> take a
>>>>>>> few days
>>>>>>> to get it all into a form that answers most of the questions.
>>>>>>> 
>>>>>>> What you will need:
>>>>>>> 
>>>>>>> 1) A working REF-0
>>>>>>> 2) A PIC or other micro to get things going
>>>>>>> 3) A GPS with a PPS output (any will do)
>>>>>>> 4) Code specific to your GPS and the needs of the REF-0
>>>>>>> 
>>>>>>> Since the Oncore needs to be set up each time it’s booted, there is
>>> no
>>>>> real
>>>>>>> advantage to using one. You still need an MCU in the mix.
>>>>>>> 
>>>>>>> More to follow.
>>>>>>> 
>>>>>>> Bob
>>>>>>> 
>>>>>>>> On Aug 7, 2015, at 5:24 AM, Graham <planophore at aei.ca> wrote:
>>>>>>>> 
>>>>>>>> Bob,
>>>>>>>> 
>>>>>>>> I would like that information too please and thank you.
>>>>>>>> 
>>>>>>>> I have a pair that is working quite well and I also have a second
>>> REF-0
>>>>>>> that I want to start testing but just haven't got round to it yet
>>> to
>>>>> figure
>>>>>>> out what is needed.
>>>>>>>> 
>>>>>>>> cheers, Graham ve3gtc
>>>>>>>> 
>>>>>>>> 
>>>>>>>>> On 2015-08-07 02:39, Bob Camp wrote:
>>>>>>>>> Hi
>>>>>>>>> 
>>>>>>>>> You need to get the Oncore running with the correct position
>>> locked in
>>>>>>> and spitting out the right strings.
>>>>>>>>> That’s all done by the CPU in the REF-1 unit. The REF-0 simply
>>> grabs
>>>>>>> the data off of the string
>>>>>>>>> as it comes by.
>>>>>>>>> 
>>>>>>>>> I’ll see if I can dig out the information and send it to you off
>>> list.
>>>>>>> It’s buried around here somewhere.
>>>>>>>>> 
>>>>>>>>> Bob
>>>>>>>>> 
>>>>>>>>>> On Aug 6, 2015, at 10:02 PM, Edesio Costa e Silva <
>>>>>>> time-nuts at tardis.net.br> wrote:
>>>>>>>>>> 
>>>>>>>>>> Thanks.
>>>>>>>>>> 
>>>>>>>>>> I have some Motorola Oncore available.
>>>>>>>>>> 
>>>>>>>>>> Can you detail this "fairly simple manipulation of the signal
>>> lines"?
>>>>>>>>>> 
>>>>>>>>>> Regards,
>>>>>>>>>> 
>>>>>>>>>> Edésio
>>>>>>>>>> 
>>>>>>>>>>> On Thu, Aug 06, 2015 at 09:57:20PM -0400, Bob Camp wrote:
>>>>>>>>>>> Hi
>>>>>>>>>>> 
>>>>>>>>>>> People got a bit ???excited??? about the level of KS box
>>>>> discussions.
>>>>>>> All of the work decoding
>>>>>>>>>>> the 15 pin connector and how to drive the REF-0 was taken off
>>> list.
>>>>>>>>>>> 
>>>>>>>>>>> Simple answer:
>>>>>>>>>>> 
>>>>>>>>>>> Yes you can run a REF-0 by it???s self. It needs a dummy string
>>> that
>>>>>>> looks like the output
>>>>>>>>>>> of a Motorola Oncore to feed it and some fairly simple
>>> manipulation
>>>>>>> of the signal lines.
>>>>>>>>>>> It will then quite happily discipline to the pps you feed it.
>>>>>>>>>>> 
>>>>>>>>>>> Bob
>>>>>>>>>>> 
>>>>>>>>>>>> On Aug 6, 2015, at 7:27 PM, Edesio Costa e Silva <
>>>>>>> time-nuts at tardis.net.br> wrote:
>>>>>>>>>>>> 
>>>>>>>>>>>> Hello Fellows!
>>>>>>>>>>>> 
>>>>>>>>>>>> Had anyone managed to run the KS-24361 REF-0, the one without
>>> GPS,
>>>>>>> as a
>>>>>>>>>>>> standalone unit? If so, can you provide some links on how to
>>>>>>> configure it?
>>>>>>>>>>>> 
>>>>>>>>>>>> The reason to try this is cost. The REF-0 unit costs USD 25 +
>>> USD
>>>>>>> 52.30
>>>>>>>>>>>> (shipping to Brazil) and I have to pay the same amount as
>>> custom
>>>>>>> taxes.
>>>>>>>>>>>> 
>>>>>>>>>>>> Right now the REF-0/REF-1 pair would be too expensive.
>>>>>>>>>>>> 
>>>>>>>>>>>> Regards,
>>>>>>>>>>>> 
>>>>>>>>>>>> Edésio
>>>>>>>>>>>> _______________________________________________
>>>>>>>>>>>> time-nuts mailing list -- time-nuts at febo.com
>>>>>>>>>>>> To unsubscribe, go to
>>>>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>>>>>>>>>>> and follow the instructions there.
>>>>>>>>> _______________________________________________
>>>>>>>>> time-nuts mailing list -- time-nuts at febo.com
>>>>>>>>> To unsubscribe, go to
>>>>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>>>>>>>> and follow the instructions there.
>>>>>>>> 
>>>>>>>> _______________________________________________
>>>>>>>> time-nuts mailing list -- time-nuts at febo.com
>>>>>>>> To unsubscribe, go to
>>>>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>>>>>>> and follow the instructions there.
>>>>>>> 
>>>>>>> _______________________________________________
>>>>>>> time-nuts mailing list -- time-nuts at febo.com
>>>>>>> To unsubscribe, go to
>>>>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>>>>>> and follow the instructions there.
>>>>>> _______________________________________________
>>>>>> time-nuts mailing list -- time-nuts at febo.com
>>>>>> To unsubscribe, go to
>>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>>>>> and follow the instructions there.
>>>>> _______________________________________________
>>>>> time-nuts mailing list -- time-nuts at febo.com
>>>>> To unsubscribe, go to
>>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>>>> and follow the instructions there.
>>>> _______________________________________________
>>>> time-nuts mailing list -- time-nuts at febo.com
>>>> To unsubscribe, go to
>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>>> and follow the instructions there.
>>> 
>>> _______________________________________________
>>> time-nuts mailing list -- time-nuts at febo.com
>>> To unsubscribe, go to
>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>> and follow the instructions there.
>>> 
>>> _______________________________________________
>>> time-nuts mailing list -- time-nuts at febo.com
>>> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>> and follow the instructions there.
>> 
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.

More information about the time-nuts mailing list