[time-nuts] time-nuts Digest, Vol 107, Issue 22

Joe Leikhim jleikhim at leikhim.com
Tue Jun 4 10:30:47 EDT 2013


Will see you then thanks 

Sent from my iPod

On Jun 4, 2013, at 2:11 PM, time-nuts-request at febo.com wrote:

> Send time-nuts mailing list submissions to
>    time-nuts at febo.com
> 
> To subscribe or unsubscribe via the World Wide Web, visit
>    https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> or, via email, send a message with subject or body 'help' to
>    time-nuts-request at febo.com
> 
> You can reach the person managing the list at
>    time-nuts-owner at febo.com
> 
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of time-nuts digest..."
> 
> 
> Today's Topics:
> 
>   1. Re: 59503A GPIB clock windows/linux software. (Hal Murray)
>   2. Re: Traceability after loss of LORAN and WWVB (Doug Calvert)
>   3. Re: Cheap 9.8Mhz Sa.22c's (Angus)
>   4. Cheap 9.8Mhz Sa.22c's (Skip Withrow)
>   5. Re: 59503A GPIB clock windows/linux software. (Tom Van Baak)
>   6. Re: 59503A GPIB clock windows/linux software. (Don Latham)
>   7. Re: 59503A GPIB clock windows/linux software. (Hal Murray)
>   8. Re: Traceability after loss of LORAN and WWVB (Jason Rabel)
>   9. Re: Traceability after loss of LORAN and WWVB (paul swed)
> 
> 
> ----------------------------------------------------------------------
> 
> Message: 1
> Date: Mon, 03 Jun 2013 16:13:21 -0700
> From: Hal Murray <hmurray at megapathdsl.net>
> To: Discussion of precise time and frequency measurement
>    <time-nuts at febo.com>
> Subject: Re: [time-nuts] 59503A GPIB clock windows/linux software.
> Message-ID:
>    <20130603231321.3C46480006F at ip-64-139-1-69.sjc.megapath.net>
> Content-Type: text/plain; charset=us-ascii
> 
> 
> h.holzach at vtxmail.ch said:
>> 2. i use the SCPI command ":ptime:time:str?" to read the time from the
>> gpsdo. if i understand correctly, the resolution of the string is 1  sencond
>> only. this would mean that if i read the time at Z + 0.9 seconds  then i get
>> Z and not Z+0.9s. this does not help much to synchronize the  clock
>> precisely with the GPSDO. or did i misunderstand something here  (which is
>> not very unlikely)?
> 
> Even though the resolution of the clock is low, you can get an accurate 
> reading if you catch it rolling over from T to T+1.
> 
> I'd make a loop that reads the time and counts how many times you get the 
> same answer.
> 
> 
> -- 
> These are my opinions.  I hate spam.
> 
> 
> 
> 
> 
> ------------------------------
> 
> Message: 2
> Date: Mon, 3 Jun 2013 21:36:25 -0400
> From: Doug Calvert <dfc-list at douglasfcalvert.net>
> To: Discussion of precise time and frequency measurement
>    <time-nuts at febo.com>
> Subject: Re: [time-nuts] Traceability after loss of LORAN and WWVB
> Message-ID:
>    <CACtKTD2Oav7GXDtNj5XLZdULLa=GJZGh3Srcy6MES97J_CmvHw at mail.gmail.com>
> Content-Type: text/plain; charset=UTF-8
> 
> On Sat, Jun 1, 2013 at 3:02 PM, Scott McGrath <scmcgrath at gmail.com> wrote:
> 
> Since the demise of LORAN and WWVB (although d-PSKer may allow us to bring
>> spectracoms and 117a's back.
> 
> 
> What/Who is d-PSKer?
> 
> 
> ------------------------------
> 
> Message: 3
> Date: Tue, 04 Jun 2013 01:43:22 -0000
> From: Angus <not.again at btinternet.com>
> To: Discussion of precise time and frequency measurement
>    <time-nuts at febo.com>
> Subject: Re: [time-nuts] Cheap 9.8Mhz Sa.22c's
> Message-ID: <152907.45109.bm at smtp154.mail.ir2.yahoo.com>
> Content-Type: text/plain; charset="us-ascii"
> 
> 
> 
> ------------------------------
> 
> Message: 4
> Date: Mon, 3 Jun 2013 20:30:32 -0600
> From: Skip Withrow <skip.withrow at gmail.com>
> To: time-nuts at febo.com
> Subject: [time-nuts] Cheap 9.8Mhz Sa.22c's
> Message-ID:
>    <CA+oSWyVJzR+5U7YDzDof6Y5jFXRMU_LheT+stHmuhW=UiwUkWw at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
> 
> There is a crystal in the sa.22 that will determin what output frequencies
> are available for output.  On the 9.8MHz and 10MHz versions it is 6X the
> nominal output frequency (58.x MHz vs 60MHz).  The sa.22 can be programmed
> to output xtal freq/2N for n up 2^16 (IIRC, it's in the manual).
> 
> Thus, you can change 15MHz units (found on telecom boards) to 10MHz (n is
> changed from 2 to 3).  I have done this.  But, you can't change 9.8MHz
> (found on different telecom cards) units to 10MHz.
> 
> Regards,
> Skip Withrow
> 
> 
> ------------------------------
> 
> Message: 5
> Date: Mon, 3 Jun 2013 20:46:23 -0700
> From: "Tom Van Baak" <tvb at LeapSecond.com>
> To: "Discussion of precise time and frequency measurement"
>    <time-nuts at febo.com>
> Subject: Re: [time-nuts] 59503A GPIB clock windows/linux software.
> Message-ID: <BB0F8A9B6F644F44B6CE29BA4F12EB06 at pc52>
> Content-Type: text/plain;    charset="iso-8859-1"
> 
>> Even though the resolution of the clock is low, you can get an accurate 
>> reading if you catch it rolling over from T to T+1.
>> 
>> I'd make a loop that reads the time and counts how many times you get the 
>> same answer.
> 
> Hal,
> 
> The hp 59309A has a talk-only mode where timestamps are output at 40 Hz; so that would narrow it down to 25 ms.
> 
> BTW, if you're curious, look at the service manual (http://ko4bb.com/manuals.php). This is a pre-microprocessor age GPIB instrument that uses a 4096-bit ROM-based state machine (A5U2) as a CPU. Very clever, very 70's.
> 
> The 59309A is a wonderful, compact, vintage instrument, but my suggestion to the OP is that it's not really suitable for use for precise time or NTP.
> 
> /tvb
> 
> 
> 
> ------------------------------
> 
> Message: 6
> Date: Mon, 3 Jun 2013 23:07:41 -0600 (MDT)
> From: "Don Latham" <djl at montana.com>
> To: "Tom Van Baak" <tvb at LeapSecond.com>,    "Discussion of precise time
>    and frequency measurement" <time-nuts at febo.com>
> Subject: Re: [time-nuts] 59503A GPIB clock windows/linux software.
> Message-ID:
>    <71122319e97ed4496f9886480630bf55.squirrel at webmail.montana.com>
> Content-Type: text/plain;charset=iso-8859-1
> 
> It also has an available BNC on the back, if you redo the the external
> voltage in, and a couple of unused cmos buffers to give a 1 pps output.
> Dob
> 
> Tom Van Baak
>> Lizeth Norman wrote:
>>> The 59309A can be updated via HPIB.
>>> I did it two ways. The first was to use windows system time and then
>>> write
>>> to the instrument. The other was to poll a M12+T and get the proper
>>> time.
>>> Sadly, both are in Labview, and as such probably aren't much help.
>> 
>> Hans Holzach wrote:
>>> i use a 59309A as a time and date display in a setup of old HP
>>> devices:
>>> 10 mhz are taken from a fury gpsdo to keep the clock stable. an HP 71B
>>> reads the time from the gpsdo via an HP-IL/RS-232 interface and
>>> delivers
>>> it to the clock via an HP-IL/HPIB interface. setting the clock looks
>>> pretty cool, there is quite some action on the display! the system is
>>> so
>>> slow, it takes several seconds until time and date are set. sorry, no
>>> linux/windows involved here...
>> 
>> Norm and Hans,
>> 
>> Were either of you able to sync the 59309A to better than a second? From
>> the schematic it looks like the P (stoP) and T (starT) commands have 1
>> second granularity and the R (Reset) command clears only the last
>> MC14518 decade counter. This would suggest that one can set to within
>> 100 ms, but no better.
>> 
>> The code that I'm using (http://leapsecond.com/tools/hp59309.c) solves
>> the 1 second problem but I wasn't able to get it to sync better than 0.1
>> second. If you have suggestions or solved this without a soldering iron,
>> let me know.
>> 
>> Thanks,
>> /tvb
>> 
>> 
>> _______________________________________________
>> 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.
> 
> 
> -- 
> "Neither the voice of authority nor the weight of reason and argument
> are as significant as experiment, for thence comes quiet to the mind."
> De Erroribus Medicorum, R. Bacon, 13th century.
> "If you don't know what it is, don't poke it."
> Ghost in the Shell
> 
> 
> Dr. Don Latham AJ7LL
> Six Mile Systems LLP
> 17850 Six Mile Road
> POB 134
> Huson, MT, 59846
> VOX 406-626-4304
> Skype: buffler2
> www.lightningforensics.com
> www.sixmilesystems.com
> 
> 
> 
> 
> ------------------------------
> 
> Message: 7
> Date: Tue, 04 Jun 2013 03:33:21 -0700
> From: Hal Murray <hmurray at megapathdsl.net>
> To: Discussion of precise time and frequency measurement
>    <time-nuts at febo.com>
> Subject: Re: [time-nuts] 59503A GPIB clock windows/linux software.
> Message-ID:
>    <20130604103321.2C33980006F at ip-64-139-1-69.sjc.megapath.net>
> Content-Type: text/plain; charset=us-ascii
> 
> 
> tvb at LeapSecond.com said:
>> The hp 59309A has a talk-only mode where timestamps are output at 40 Hz; so
>> that would narrow it down to 25 ms.
> 
> You can get (much?) better than 25 ms if the timestamps are locked to the 
> master clock or PPS.
> 
> If not, you can also get into hanging-bridge type adventures.  :)
> 
> 
>> BTW, if you're curious, look at the service manual (http://ko4bb.com/
>> manuals.php). This is a pre-microprocessor age GPIB instrument that uses a
>> 4096-bit ROM-based state machine (A5U2) as a CPU. Very clever, very 70's.
> 
> I was designing hardware back in those days, and writing microcode too.  The 
> good old days really were "good", at least in my memories.
> 
> If you get more than ballpark of 20 states in your state machine, it's often 
> simpler to think of the problem as software rather than hardware.  That 
> probably works better if you have some experience writing microcode.
> 
> At the hardware level, for the gear I worked on, each instruction had a 
> next-PC field.  One trick was to implement branches by ORing bits into the 
> bottom bits of the next-PC.  The assembler did most of the work.
> 
> For anything bigger than roughly 20 states, we would write a real assembler.  
> That's not a lot of work if you start from a previous example.  Just change 
> all the keywords and matching dictionary.
> 
> 4096 is 512x8, 9 address bits and 8 data bits, so you get X bits of PC and 
> 9-X bits to branch on.  You can get more branch bits by using a mux keyed off 
> some high-order PC bits or something like that.  (That's more work for the 
> assembler, but the programmer doesn't have to think about it.)
> 
> 
> 
> 
> 
> -- 
> These are my opinions.  I hate spam.
> 
> 
> 
> 
> 
> ------------------------------
> 
> Message: 8
> Date: Tue, 4 Jun 2013 08:03:28 -0500
> From: "Jason Rabel" <jason at extremeoverclocking.com>
> To: <time-nuts at febo.com>
> Subject: Re: [time-nuts] Traceability after loss of LORAN and WWVB
> Message-ID: <000001ce6123$e84af820$b8e0e860$@extremeoverclocking.com>
> Content-Type: text/plain;    charset="us-ascii"
> 
> Short Answer (Long Answer is in the PDF): http://www.febo.com/pages/wwvb_psk/WWVB%20d-psk-r%2003302013.pdf
> 
>> What/Who is d-PSKer?
> 
> 
> 
> ------------------------------
> 
> Message: 9
> Date: Tue, 4 Jun 2013 09:11:18 -0400
> From: paul swed <paulswedb at gmail.com>
> To: Discussion of precise time and frequency measurement
>    <time-nuts at febo.com>
> Subject: Re: [time-nuts] Traceability after loss of LORAN and WWVB
> Message-ID:
>    <CAD2JfAgKZiwKyFNQUo3PSD_YYiBny_vjWQVj6G4KBBASovxqiQ at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
> 
> d-psk-r is a unit that removes the new wwvb phase modulation so that
> traditional/vintage phase tracking receivers can work. Its essentially a
> costa loop for 60 Khz. Its not a kit and does work. But as with all things
> homebrew can always use improvements. Search the time nuts archives the
> infos all there.
> 
> Paul
> WB8TSL
> 
> 
> On Tue, Jun 4, 2013 at 9:03 AM, Jason Rabel
> <jason at extremeoverclocking.com>wrote:
> 
>> Short Answer (Long Answer is in the PDF):
>> http://www.febo.com/pages/wwvb_psk/WWVB%20d-psk-r%2003302013.pdf
>> 
>>> What/Who is d-PSKer?
>> 
>> _______________________________________________
>> 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
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> 
> End of time-nuts Digest, Vol 107, Issue 22
> ******************************************


More information about the time-nuts mailing list