[time-nuts] Lady Heather and Lucent RFTGm-II-XO / RFTGm-II-Rb

[Mark Sims]

If you can build the source code I can send you the latest version.   Linux is 
easy to do.  Not many people seem to be able to handle the Windows build but if 
you are familiar with Visual Studio (particularly command line builds) it is 
easy.   Contact me off list for the code.

I have figured out how to get the antenna current.   It reports two antenna 
voltages which are the readings each side of a 100 ohm series resistor...  
voila... current!   BTW, antenna short circuit current is around 300 mA.


-

> Have you built a special version of LH to work with the RFTGm’s?  If so, is 
> it possible to get a copy?
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Re: [time-nuts] Lady Heather and Lucent RFTGm-II-XO / RFTGm-II-Rb

[Rodger Adams via time-nuts]

Mark,

Have you built a special version of LH to work with the RFTGm’s?  If so, is it 
possible to get a copy?

Thanks,

Rodger


> On May 28, 2017, at 2:15 AM, Mark Sims  wrote:
> 
> I have Lady Heather working fairly well with the RFTGm's.I used a serial 
> port monitor program to capture the traffic in and out of the serial port and 
> used the Lucent control program to set and read various parameters.  By 
> analyzing the captured traffic and comparing the results to what the Lucent 
> program was reporting / sending I worked out the protocol and message formats.
> 
> The one message that I have problems with is the one that reports the EFC DAC 
> voltage and temperature.  The message appears to be reporting the DAC value 
> and temperature as a 16 bit integer.   Scaling that to actual values could be 
> a problem.  The DAC is not that big a deal... I scale it to a 0-100% value... 
> no real need to be concerned with the actual voltage.  The temperature value 
> will require a lot of work.  It has an 8 bit granularity and seldom changes 
> more than one step.
> 
> One annoying thing about the RFTGm's is that they don't report satellite 
> positions (just signal levels)... so no nice antenna survey maps are possible.
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Re: [time-nuts] Next Aug 21 eclipse and time flow

[Jim Palfreyman]

Personally I go with the Nature article. The other papers look like they
are anomaly hunting because they have a known event.

Having said that, we have two H masers at our observatory in Hobart and we
have a system set up to measure their phase difference down to about 0.03
ns. I will report back any anomaly.

We, of course, are not in the path of the eclipse, however gravitationally
there is still an alignment. Just through the Earth.


Jim Palfreyman


On 29 May 2017 at 08:17, iovane--- via time-nuts  wrote:

> On august 21 2017 a solar eclipse will sweep USA from coast to coast. A
> lifetime opportunity to do coordinated experiments to check this or that.
> One of the questions that doesn't have a final answer yet is whether or not
> solar eclipses could affect the flow of time. They exist conflicting
> reports: Negative: http://www.nature.com/nature/journal/v402/n6763/full/
> 402749a0.html Positive: http://home.t01.itscom.net/
> allais/blackprior/zhou/zhou-1.pdf  http://home.t01.itscom.net/
> allais/blackprior/zhou/zhou-2.pdfPersonally I believe that the positive
> results were due to spurious responses of the atomic clocks to something
> else than gravity, or the clocks failed for some reason (e.g. jumping
> crystals then steered), or lower quality clocks had been sold to China.
> Anyway the recorded data do show an anomaly.As far as I know, no atomic
> clock tests are planned anywhere for that circumstance, but sincerely I
> don't believe this is the truth.Maybe the US time-nuts community, using its
> plenty
>  of atomic clocks, could give the final answer doing tests during the
> above mentioned eclipse.US time-nuts, what about the idea of doing
> yourselves a large scale coordinated test? Or do you actually believe that
> this question is already definitively closed?(Even discovering that atomic
> clocks might respond to someting else than gravity would be of great
> interest).Antonio I8IOV
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[time-nuts] Next Aug 21 eclipse and time flow

[iovane--- via time-nuts]

On august 21 2017 a solar eclipse will sweep USA from coast to coast. A 
lifetime opportunity to do coordinated experiments to check this or that. One 
of the questions that doesn't have a final answer yet is whether or not solar 
eclipses could affect the flow of time. They exist conflicting reports: 
Negative: http://www.nature.com/nature/journal/v402/n6763/full/402749a0.html 
Positive: http://home.t01.itscom.net/allais/blackprior/zhou/zhou-1.pdf  
http://home.t01.itscom.net/allais/blackprior/zhou/zhou-2.pdfPersonally I 
believe that the positive results were due to spurious responses of the atomic 
clocks to something else than gravity, or the clocks failed for some reason 
(e.g. jumping crystals then steered), or lower quality clocks had been sold to 
China. Anyway the recorded data do show an anomaly.As far as I know, no atomic 
clock tests are planned anywhere for that circumstance, but sincerely I don't 
believe this is the truth.Maybe the US time-nuts community, using its plenty 
 of atomic clocks, could give the final answer doing tests during the above 
mentioned eclipse.US time-nuts, what about the idea of doing yourselves a large 
scale coordinated test? Or do you actually believe that this question is 
already definitively closed?(Even discovering that atomic clocks might respond 
to someting else than gravity would be of great interest).Antonio I8IOV
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Re: [time-nuts] Lady Heather and Lucent RFTGm-II-XO / RFTGm-II-Rb

[Tom Van Baak]

Mark,

> One annoying thing about the RFTGm's is that they don't report satellite 
> positions (just signal levels)...
> so no nice antenna survey maps are possible.

Well, yes and no. It is true that signal levels can only be *measured*. And 
you've got that. No problem.

Now, realize that satellite positions are only ever *calculated* by a GPS 
receiver, not actually measured. So it's quite easy to generate satellite maps 
with or without a working GPS receiver. I mean, each and every GPS SV 
is-where-it-is-right-now regardless if you exist or not, if you've got a 
receiver or not, if your receiver outputs positions or not. Make sense?

So all you need is:
- a copy of a recent constellation almanac or ephemeris (on the 'net, or from 
quality GPS receivers, especially in binary mode),
- the approximate UTC date/time,
- your approximate location,
- a handful of wonderful orbital mechanics equations, which you can look up in 
any GPS textbook or online tutorial.

If you want to see an example of this, fire up Trimble Planning.exe, which is 
part of the free TBolt s/w suite (along with TBoltMon.exe, etc.). Again, 
remember that the whole point of GPS is that the precise location of each SV 
must be knowable by the CPU; not measured with a telescope or directional 
antenna or something. So it's quite easy to create maps for any and all known 
satellites once you look-up the orbit parameters. There are apps / programs / 
web sites that do this. NASA used to have the wonderful JTrack3D. Instead check 
out http://www.heavens-above.com/ for info.

For extra credit... The joke is that LH has a feature which "hides" the user's 
lat/lon. Privacy? Nope, LH still reports precise UTC date, time, PRN, Az, El, 
and Doppler! So it's not rocket science (well, it is in a way) to solve that 
nice set of precise and overdetermined numbers on the screen to obtain a good 
guess at the redacted position. Oops.

/tvb

- Original Message - 
From: "Mark Sims" 
To: 
Sent: Saturday, May 27, 2017 11:15 PM
Subject: [time-nuts] Lady Heather and Lucent RFTGm-II-XO / RFTGm-II-Rb


>I have Lady Heather working fairly well with the RFTGm's.I used a serial 
>port monitor program to capture the traffic in and out of the serial port and 
>used the Lucent control program to set and read various parameters.  By 
>analyzing the captured traffic and comparing the results to what the Lucent 
>program was reporting / sending I worked out the protocol and message formats.
> 
> The one message that I have problems with is the one that reports the EFC DAC 
> voltage and temperature.  The message appears to be reporting the DAC value 
> and temperature as a 16 bit integer.   Scaling that to actual values could be 
> a problem.  The DAC is not that big a deal... I scale it to a 0-100% value... 
> no real need to be concerned with the actual voltage.  The temperature value 
> will require a lot of work.  It has an 8 bit granularity and seldom changes 
> more than one step.
> 
> One annoying thing about the RFTGm's is that they don't report satellite 
> positions (just signal levels)... so no nice antenna survey maps are possible.


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[time-nuts] Lady Heather and Lucent RFTGm-II-XO / RFTGm-II-Rb

[Mark Sims]

I have Lady Heather working fairly well with the RFTGm's.I used a serial 
port monitor program to capture the traffic in and out of the serial port and 
used the Lucent control program to set and read various parameters.  By 
analyzing the captured traffic and comparing the results to what the Lucent 
program was reporting / sending I worked out the protocol and message formats.

The one message that I have problems with is the one that reports the EFC DAC 
voltage and temperature.  The message appears to be reporting the DAC value and 
temperature as a 16 bit integer.   Scaling that to actual values could be a 
problem.  The DAC is not that big a deal... I scale it to a 0-100% value... no 
real need to be concerned with the actual voltage.  The temperature value will 
require a lot of work.  It has an 8 bit granularity and seldom changes more 
than one step.

One annoying thing about the RFTGm's is that they don't report satellite 
positions (just signal levels)... so no nice antenna survey maps are possible.
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Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

[paul swed]

Though I will never see a OSA 3000, It certainly sounds like a hack could
be done to obtain a Cs off reference. But then when you don't actually have
one you can make comments like that.
Sounds nice.
Regards
Paul
WB8TSL

On Sun, May 28, 2017 at 8:20 AM, Magnus Danielson <
mag...@rubidium.dyndns.org> wrote:

> Hi,
>
> On 05/28/2017 11:52 AM, "Björn Gabrielsson" wrote:
>
>> So while I'm eager to see Donald's results, I question their merit. The
>>>
>> 5061 standards already have a very convenient Cs-Off switch right on the
>> front panel. It is there so you get the pure 10811 performance when you
>> need it. Use it. In fact there's lots of people run their precious 5061
>> in
>>
>>> Cs-Off mode 23.9 hours a day and just turn on the Cs once a day, or once
>>>
>> a
>>
>>> week, to re-cal the oscillator. It's not there just to conserve cesium;
>>>
>> you also get full 10811 short-term performance. Note also some 5061 have
>> a
>>
>>> short/long time-constant switch which also helps you tailor the ADEV you
>>>
>> want out of the instrument.
>>
>>> /tvb
>>>
>>
>> Very nice design by HP.
>>
>> For the same era design, the OSA (telecom) module made other choices. When
>> turning off CS, they turn off power to the output module and the efc
>> tuning circuit.
>>
>> So even if there is a nice and warm BVA inside - without burning CS - the
>> standard output is not working and also its off any manual tuning.
>>
>
> In addition, and I consider this somewhat of a design flaw, the external
> voltage reference to the oscillator (pre-BVA or BVA) is also powered of, so
> it drift south rather than stay put. Otherwise it would have been easy to
> trim the oscillator for zero lock enforcement and then free-wheel on the
> OCXO when Cs is powered down.
>
> The OSA 3000 and 3100 cesiums are nice analog cesiums, but lacking the
> refinement of digitally controlled that came later.
>
> Cheers,
> Magnus
>
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Re: [time-nuts] GR Connectors

[Tom Van Baak]

> worthwhile.  I guess they can bury all this stuff with me, like King Tuts 
> tomb...

Alternative use for your pile of surplus connectors:

http://leapsecond.com/pages/chess/

/tvb

- Original Message - 
From: "Jeff Kruth via time-nuts" 
To: 
Sent: Sunday, May 28, 2017 8:59 AM
Subject: Re: [time-nuts] GR Connectors


> GR made several coaxial connector series: the obvious 874, the 8.5 GHz  
> very low residual VSWR GR-900 (IIRC 14 mm bore) and the GPC-7 (7 mm bore)  18 
> GHz precision connector, a very rare precursor to the APC-7 with a 1/4 turn  
> locking collar, only place I saw it was in the HP 1965 catalog, brief 
> lifetime.  I have a few in my collection of MW history stuff.
> 
> GR was the cats meow for a long time. I have a pile of the 900 & 874  
> stuff, just because I like it. The AIL hot/cold load that uses 900 is still  
> worthwhile.  I guess they can bury all this stuff with me, like King Tuts  
> tomb...
> 
> 73
> Jeff Kruth
> WA3ZKR
> 
> 
> 
> In a message dated 5/28/2017 5:53:31 A.M. Eastern Daylight Time,  
> time-nuts-requ...@febo.com writes:
> 
> Message:  17
> Date: Sun, 28 May 2017 05:15:52 -0400
> From: Scott McGrath  
> To: Discussion of precise time and frequency  measurement
> 
> Subject: Re:  [time-nuts] Two pieces of old General Radio Freq. Nuts
> Message-ID:  
> Content-Type:  text/plain;charset=utf-8
> 
> The GenRad 874 connector was  good to 4.5 Ghz  and took a Banana plug in 
> the center conductor without  changing electrical  characteristics!!!
> 
> http://www.ietlabs.com/pdf/GR_Experimenters/1948/GenRad_Experimenter_Oct_194
> 8.pdf
> 
> Not  bad for a connector designed in 1948!   
> 
> It was largely  supplanted by the APC-7 connector from Bunker-Ramo which 
> was also a  hermaphrodite design but had a 18 Ghz frequency limit
> 
> Lots of Tek  calibrators used this connector due to its good impedance 
> matching without  requiring obsessive connector maintenance as the APC-7 does 
> (cleaning, gauging  and finger replacement)
> 
> 
> ___
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Re: [time-nuts] GR Connectors

[Jeff Kruth via time-nuts]

GR made several coaxial connector series: the obvious 874, the 8.5 GHz  
very low residual VSWR GR-900 (IIRC 14 mm bore) and the GPC-7 (7 mm bore)  18 
GHz precision connector, a very rare precursor to the APC-7 with a 1/4 turn  
locking collar, only place I saw it was in the HP 1965 catalog, brief 
lifetime.  I have a few in my collection of MW history stuff.
 
GR was the cats meow for a long time. I have a pile of the 900 & 874  
stuff, just because I like it. The AIL hot/cold load that uses 900 is still  
worthwhile.  I guess they can bury all this stuff with me, like King Tuts  
tomb...
 
73
Jeff Kruth
WA3ZKR
 
 
 
In a message dated 5/28/2017 5:53:31 A.M. Eastern Daylight Time,  
time-nuts-requ...@febo.com writes:

Message:  17
Date: Sun, 28 May 2017 05:15:52 -0400
From: Scott McGrath  
To: Discussion of precise time and frequency  measurement

Subject: Re:  [time-nuts] Two pieces of old General Radio Freq. Nuts
Message-ID:  
Content-Type:  text/plain;charset=utf-8

The GenRad 874 connector was  good to 4.5 Ghz  and took a Banana plug in 
the center conductor without  changing electrical  characteristics!!!

http://www.ietlabs.com/pdf/GR_Experimenters/1948/GenRad_Experimenter_Oct_194
8.pdf

Not  bad for a connector designed in 1948!   

It was largely  supplanted by the APC-7 connector from Bunker-Ramo which 
was also a  hermaphrodite design but had a 18 Ghz frequency limit

Lots of Tek  calibrators used this connector due to its good impedance 
matching without  requiring obsessive connector maintenance as the APC-7 does 
(cleaning, gauging  and finger replacement)


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Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

[Magnus Danielson]

Hi,

On 05/28/2017 11:52 AM, "Björn Gabrielsson" wrote:

So while I'm eager to see Donald's results, I question their merit. The

5061 standards already have a very convenient Cs-Off switch right on the
front panel. It is there so you get the pure 10811 performance when you
need it. Use it. In fact there's lots of people run their precious 5061
in

Cs-Off mode 23.9 hours a day and just turn on the Cs once a day, or once

a

week, to re-cal the oscillator. It's not there just to conserve cesium;

you also get full 10811 short-term performance. Note also some 5061 have
a

short/long time-constant switch which also helps you tailor the ADEV you

want out of the instrument.

/tvb


Very nice design by HP.

For the same era design, the OSA (telecom) module made other choices. When
turning off CS, they turn off power to the output module and the efc
tuning circuit.

So even if there is a nice and warm BVA inside - without burning CS - the
standard output is not working and also its off any manual tuning.


In addition, and I consider this somewhat of a design flaw, the external 
voltage reference to the oscillator (pre-BVA or BVA) is also powered of, 
so it drift south rather than stay put. Otherwise it would have been 
easy to trim the oscillator for zero lock enforcement and then 
free-wheel on the OCXO when Cs is powered down.


The OSA 3000 and 3100 cesiums are nice analog cesiums, but lacking the 
refinement of digitally controlled that came later.


Cheers,
Magnus
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Re: [time-nuts] Fwd: HP5061B Versus HP5071 Cesium Line Frequencies

[Björn Gabrielsson]

> So while I'm eager to see Donald's results, I question their merit. The
5061 standards already have a very convenient Cs-Off switch right on the
front panel. It is there so you get the pure 10811 performance when you
need it. Use it. In fact there's lots of people run their precious 5061
in
> Cs-Off mode 23.9 hours a day and just turn on the Cs once a day, or once
a
> week, to re-cal the oscillator. It's not there just to conserve cesium;
you also get full 10811 short-term performance. Note also some 5061 have
a
> short/long time-constant switch which also helps you tailor the ADEV you
want out of the instrument.
> /tvb

Very nice design by HP.

For the same era design, the OSA (telecom) module made other choices. When
turning off CS, they turn off power to the output module and the efc
tuning circuit.

So even if there is a nice and warm BVA inside - without burning CS - the
standard output is not working and also its off any manual tuning.

--

Björn




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Re: [time-nuts] Two pieces of old General Radio Freq. Nuts

[Scott McGrath]

The GenRad 874 connector was good to 4.5 Ghz  and took a Banana plug in the 
center conductor without changing electrical characteristics!!!

http://www.ietlabs.com/pdf/GR_Experimenters/1948/GenRad_Experimenter_Oct_1948.pdf

Not bad for a connector designed in 1948!

It was largely supplanted by the APC-7 connector from Bunker-Ramo which was 
also a hermaphrodite design but had a 18 Ghz frequency limit

Lots of Tek calibrators used this connector due to its good impedance matching 
without requiring obsessive connector maintenance as the APC-7 does (cleaning, 
gauging and finger replacement)





Content by Scott
Typos by Siri
> On May 28, 2017, at 12:21 AM, djl  wrote:
> 
> Yep, GR once made the best. The GR connector had at least three things going; 
> as noted hermaphroditic. No need for several sexes. Second, they are seamless 
> 50 ohms, very very small reflections at the connection. Third, banana plugs 
> (also a GR idea, I think) fit in the center "post" of the connector without 
> wrecking anything. GR also made an hermaphroditic connector good to several 
> GHz before passing into legend. . .
> Don
> 
> 
>> On 2017-05-27 05:01, Bob kb8tq wrote:
>> Hi
>>> On May 26, 2017, at 11:21 PM, Gary Woods  wrote:
 On Mon, 22 May 2017 05:59:59 -0700, you wrote:
 https://goo.gl/photos/tygN5ZFeFLUhc4zX6
 Near Portland Oregon
>>> Neat stuff...did anybody but GR use those hermaphrodite connectors?
>> At one time, GR was pretty much the only source for a wide range of RF
>> and microwave test gear. Anything that was going to work with that gear
>> may have come with the GR connectors. That includes stuff like attenuators,
>> cables, and other bits of “lab clutter”. When you checked the box for the
>> GR connectors, the price went up quite a bit. That made the gizmos with
>> the connectors on them a bit more rare than they otherwise would be.
>> Bob
>>> I have
>>> an adapter for them that came with a wide-band amplifier; "delay line"
>>> type, with a whole row of, I think, 6AK5s in it.
>>> --
>>> Gary Woods AKA K2AHC- PGP key on request, or at 
>>> home.earthlink.net/~garygarlic
>>> Zone 5/4 in upstate New York, 1420' elevation. NY WO G
>>> ---
>>> This email has been checked for viruses by AVG.
>>> http://www.avg.com
>>> ___
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>> ___
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> 
> -- 
> Dr. Don Latham
> PO Box 404, Frenchtown, MT, 59834
> VOX: 406-626-4304
> 
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Re: [time-nuts] GNSS Disciplined Clock

[Mike Cook]

> Le 27 mai 2017 à 21:26, Ebrahim Roghanizad  a écrit :
> 
> Dear Chris
> 
> As far as I know, atmospheric effect can not be compensated by looking at
> satellites from all over the sky and averaging, since it does not have a
> random nature, rather it introduces bias to the solution. For example, if
> atmospheric effect is not removed, one can not get a relative position
> accuracy of sub-meter in long distances even by employing the method of
> RTK. All I said here is about position. Now, I would like to know about the
> output of time in this condition. What is the utmost reachable accuracy for
> a timing output from a GNSS receiver? I do not mean the precision that
> reflects the noise behavior. I think that the best result is obtained when
> the receiver supports dual frequency in order be able to deal with
> ionospheric delay. Am I right? In that case, is there any GNSS receiver
> with this ability?
> 

 I don’t know of any and over time have been looking for one . I guess there is 
no market for a pure GNSS solution. Current L1 only timing receivers can offer 
down to +/-6ns accuracy with quantization error data allowing correction of 
their PPS output down to the stability of the GPS signal. Using that data and 
available cheap delay line chips the 1PPS accuracy deliverable can be reduced 
to around +/-2-3ns .
It appears to be cheaper to use just the L1 derived time to lock better 
oscillators for better precision than that. 


> Thanks a lot
> 
> On Thu, May 25, 2017 at 10:01 PM, Chris Albertson > wrote:
> 
>> The long term stability of GPS is very good.  Some one here will point
>> out exactly how one measures it.   But roughly when speaking of
>> accuracy you always need to specify a time interval. For example
>> if the 1PPS is "off" by 15ns that is not bad and yes there are much
>> better systems if you need to measure time intervals on the order of
>> one second.   But if the signal is "off" by 15 ns over 100,000 seconds
>> that is well, 100,000 time better.
>> 
>> This is a basic reference and for some specialized end use case you
>> might couple it with other equipment.  Many of the concerns you had,
>> such as effects of the atmosphere get averaged out because the unit is
>> looking at satellites from all over the sky.  (averaging over space)
>> And you do git better results with better antenna locations that are
>> away from multi-path and have a 360 degree view of the horizon.  But
>> notice the unit has an temperature stabilized crystal oscillator that
>> is stable over many seconds. an is much more stable in the short term
>> then is a GPS receiver.  Trimble uses this crystal to average over
>> time
>> 
>> You also have to ask where is the tine data going to be used.  Are you
>> synchronizing a computer's internal clock or trying to measure the
>> frequency of a microwave transmitter
>> 
>> SO it falls back to the old thing about there being no "better" only
>> better for a specific use case.
>> 
>> Some of use were lucky enough to buy Trimble Thunderbolts, a previous
>> version of this unit when they were on eBay for $100 each.   For those
>> without 5 digits budget they ar pretty much the Gold Standard.  I have
>> mine installed with a good filtered DC power supply and an outdoor
>> antenna on mast well above the roofs of surrounding buildings. I
>> get long term stability of about one part in 10E13.   Yes 13 digits
>> over long periods.   (I think?)  It is really hard to know because my
>> measurement system is a little circular referenced
>> 
>> On Thu, May 25, 2017 at 6:27 AM, Ebrahim Roghanizad
>>  wrote:
>>> Dear members
>>> 
>>> I am a new amateur member in your group. Maybe my question has been
>> asked.
>>> Recently I found Trimble Mini-T GG, whose data sheet is attached, as a
>> good
>>> GNSS disciplined time reference. I would like to know if there exists a
>>> more accurate one, since it does not employ dual frequencies to
>> compensate
>>> ionospheric delay, though it handles both GPS and GLONASS. Besides, could
>>> anyone guide me about the presented accuracy in the datasheet? There, it
>> is
>>> stated that "When operating in Over Determined Timing Mode, the accuracy
>> of
>>> pulse per second (PPS) is within 15 nanoseconds of GNSS/UTC." Does it
>> mean
>>> that it includes both bias and the noise? In other words, is it true to
>> say
>>> that "The time-synchronization error between two of them with a long
>>> distance is less than 2*15 ns"?
>>> 
>>> Best Regards
>>> 
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>> 
>> 
>> --
>> 
>> Chris Albertson
>> Redondo Beach, California
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