Hal,
Except for a few magic target frequencies, the output will have
occasional (or frequent) missing or extra
cycles. The output will be clean if you are dividing by a power of 2.
(By switching from 10 MHz to 8
MHz, you have changed from frequent to occasional.)
Not true that
Hi Tony,
that's consistent with what I remember. Do you have the capability to count
the number of 10MHz pulses per second to see if it is phase-coherent with
the UTC 1PPS pulse?
I am thinking that the software may be using statistics to approximate 10
million cycles per second, which
Hi Graham,
its not a GPSDO though, not even a simple one :)
It does not discipline an oscillator. It generates the output by
mathematically calculating how many phases it has to add/drop in a second, then
digitally adds/drops/extends/retards the phase of the output clock to achieve
an
Hal,
I guess that depends on your definition of disciplined.
The products that I am familiar with don't consider adjusting phase length
of an asynchronously running oscillator on a cycle-to-cycle basis thousands
of times per second to try to fit 10 million of them (or whatever your
Hi Tom,
last time I looked at these I tried figuring out what they were doing. It
is very hard to get measurement data, our TSC did not converge on their
signal, and looking at the output on a scope revealed only a bunch of crazy
random phase jumps. I guess one could use a counter to
Good point.
I am a sucker for great surplus equipment too, in fact I have two rooms
full of stuff most of which is used from time to time.. I envy Tom's
collection.
I think we need to have a Time Nuts For Dummies article written that
takes J. Vig's writing and puts it into much less of a
Graham,
I think that is the real challenge here: most folks don't know what
precise means for them. Timing is such a novel technology that most folks are
amazed that we are trying to get parts per trillion (or better) accuracy and
stability!
We get customers all the time that want very
So does anyone know how/why he died?
Does anyone have the actual sources for his tools? All I know is that he
told me he used a very old database program to write them under Borland or
something like that..
Bye,
Said
In a message dated 6/26/2014 12:16:18 Pacific Daylight Time,
I dislike TSIP quite a bit. It's a disaster in my opinion if you are not
intimately familiar already with the Trimble binary commands, and exists in
a number of inconsistent and non-compatible dialects as far as I know. No
way for a human to enter a simple command in a simple text terminal,
Tom,
airflow, or changes in airflow are typically much worse for ADEV than
actual ambient temperature changes in still air.
In still air for example a typical Eurocan DOCXO will have a case temp of
about 55C to 60C at 25C ambient.
Turn on any kind of significant airflow over that part and
Wow,
that's a shock.
He was such a nice guy, always supporting requests for changes etc. Very
sad. He was quite young as well!
Our condolences to his wife and family.
Said
In a message dated 6/20/2014 13:58:36 Pacific Daylight Time,
timen...@paesler.de writes:
Dear group,
It would be good to understand which receivers are adversely affected by
this.. the USCG did not list affected vendors/devices..
In a message dated 5/15/2014 15:19:51 Pacific Daylight Time,
mag...@rubidium.dyndns.org writes:
Hi fellow time-nuts,
I think this message is interesting. It
Hi Hans,
in order not to chase the tempco and aging algorithm (it will reset the
values by itself every 10 minutes while locked to GPS as you have noted) you
may simply turn tempco and aging compensation off manually during your test
period.
This can be done by the serv:tas x, yy...
Hello everyone,
let me address the below claims and commentary which was posted without
first consulting with us.
Microsemi has recently seen a slightly higher failure rate of the CSAC
oscillators than expected. A small percentage of our customers have been
adversely affected by this
Hello everyone,
sorry for the plug, but we just announced a new $568 complete GPSDO
reference kit.
This unit is a tiny desktop unit with 10m antenna, power supply, cables,
CD, and other accessories. It is a low cost addition to our Fury GPSDO line,
and contains a really good TCXO, a
Jim,
when I did the test on the 53132A, I did the test with the two signals on
top of each other with a very small cable offset of 400ps, then I added a
10ns delay line to the B signal just to see if the counter would behave
differently. Here are the results, pretty much looks identical
Guys,
on this subject, we put together and qualified a convenient and complete
(fairly) low-cost timing-compatible GPS antenna kit that includes all the
mounting materials, 150 feet of cable, all the connectors, and down to the
last screw, nut, and bolt everything one would need to mount
Michael,
use a simple BNC T-splitter. Works perfectly for me as long as both GPS
carry the same antenna voltage. No loss in signal quality evident from the
C/No readings, and dirt-cheap. No need to over-complicate this.
bye,
Said
In a message dated 2/4/2014 14:41:40 Pacific Standard
I hope this thread dies here.
In a message dated 1/19/2014 13:22:10 Pacific Standard Time,
a...@comcast.net writes:
On 14-01-19 03:20 PM, Chris Albertson wrote:
My feverish brain now cranks out that all we need is a electromechanical
WWVB receiver, thus no active electronic parts. That
The latest receivers are surprisingly resilient to GPS jamming.
We tried jamming effects on all sorts of different GPS units ourselves,
and the M12's go out right away for example, while the uBlox units are tough
to jam. The new generation 7 ublox with Glonass etc should be even harder
to
Hi Hal,
still pretty impressive results, thanks for sharing the data.
bye,
Said
In a message dated 1/3/2014 17:10:13 Pacific Standard Time,
hmur...@megapathdsl.net writes:
saidj...@aol.com said:
Your plots don't show the wave being reflected by the cable end, and
bouncing back and
Hello,
fyi KF5OBS did a nice video review of the CSAC GPSDO (and Lecroy high end
scope) that's posted on Youtube now:
http://www.youtube.com/watch?v=CogN630jUSsfeature=c4-overviewlist=UU_XdpUc
sSigyf4JrrPtI5eA
bye,
Said
___
time-nuts mailing
Hi John,
well, I think he must have meant a new car back in 1971 :) That would be
about right. It's not quite THAT expensive.
Symmetricom seized to exist as an independent company a couple of days ago,
they were bought out by MicroSemi..
They do make great products, for sure. Please note
Forgot one comment: the good parts' plot also shows a very nice crystal
retrace stabilization in the red EFC trace over about the first 6 days or so.
After that the crystal goes into it's long term crystal aging mode.
Retrace is one big reason why its best to let crystals run continuously..
Sorry in advance guys,
I could not resist doing a short comparison between our LC_XO module and
this new Selig/RF-Suisse 1x1 module. Please excuse this blatantly biased
comparison:
The Selig module is slightly larger, and consumes about the same amount of
power as the LC_XO (TCXO
John,
have you taken a look at the Mini-JLT?
Its compatible, just supports SCPI/NMEA instead of TSIP.
bye,
Said
In a message dated 10/29/2013 17:14:22 Pacific Daylight Time,
j...@westmorelandengineering.com writes:
Hello Bob,
Guess that is a shame - looked like a nice product and
HP/Agilent/Symmetricom 58535A splitter/amplifier works great.
Just unfortunate that they always come in N connector variant.
Sometimes available dirt-cheap on Ebay..
They have 1-to-2 all the way up to 1-to-8 variants.
In a message dated 10/25/2013 15:34:59 Pacific Daylight Time,
Hi Rick, Tom,
one little bit of knowledge I learned: I like the HP 54701A FET probes for
frequency-domain stuff.
Available for $300 on Ebay sometimes. I built a small power supply for one
of mine, and use it as a probe for my Spectrum analyzer and scopes. Almost
indestructable.
It
Frank,
try GPSD on Linux:
http://gpsd.berlios.de/hardware.html
Bye,
Said
In a message dated 10/16/2013 14:50:19 Pacific Daylight Time,
hp_cisco...@yahoo.com writes:
Hi,
What NTP REFCLOCK can be used for a Jackson Fury?
I know that the Jackson Fury docs suggest using:
Paul,
try the Jackson Labs GPSTCXO eval kit. Comes with GPS antenna, USB
comm/power cable, and board.
You can get a Hammond enclosure for it for less than $20, and have a
complete desktop system for less than $400 new. Probably the lowest-cost new
way to go other than Ebay-used or
Guys,
there is only one problem: there is just no way they can claim only 1
second error in a 1000 years unless they also have a GPS receiver for
calibration in there, which kind of mutes the point as that has been done using
wwvb
etc. Let's do the math:
1/ (1000 * 365 * 24 *3600) =
Hi Tom,
yes, the GPSTCXO has a pretty good typical phase noise above 100Hz or so
for being just a TCXO, competitive to or even a bit better than some good
SC-cut OCXO's. Compare that to the Trimble Mini-T for example which has a
noise floor spec of only -145dBc/Hz according to the Trimble
Hi Bob,
it's not +/-100ns on all receivers.
Our Fury GPSDO that uses Motorola designed M12M receivers allow +/-1ns
antenna delay phase adjustment resolution. No effect on timing stability.
Almost all of our other products using uBlox GPS also allow +/-1ns antenna
delay phase adjustment
Here is my experience with trying to get one of these for very low noise
ADEV measurements:
* waited for some years for one to pop up on Ebay/Time-Nuts/Craigslist etc.
I even sent a couple of BVA WANTED emails to time-nuts in the past, no
response from anyone.
* called the factory, they
Greg,
the only power source I am aware off that can provide the ~5W power
required by that Novus box for 10-12 years with 20lbs weight limit without any
external power sources or maintenance is a radioisotope thermoelectric
generator (RTG) such as those used on Spacecraft. The Russians
Ed,
the calculation is the same, however the numbers are 100ps for 53132A
versus 350ps, and I have not seen an average systemic offset being displayed on
any of the 3x 53132A units I use, and I see one on the SR-620. That's why
I sent it into SRS for calibration, paid the $$$ and got it
Hi Volker,
there are some issues here, first the worst case frequency systematic
uncertainty is 100ps for the 53132A, not 350ps as on the SRS unit or 500ps as
you stated. So they are not the same, they are 3.5x different.
From the Agilent manual:
Systematic Uncertainty:
Agilent 53131A
Hello Claude,
that gap is a classic crystal jump. It could be caused by the crystal
changing frequency by itself, or by being hit with e.g. gamma particles etc.
Could also have been instigated by vibration or shock to the unit.
You should be seeing 6+ sats at all times though, your plot
Hui,
rent one of each if you can before you make your choice. I have both, and
the HP unit is much easier to use once you know which button sequence to
push to get more than just Frequency/Time-Interval type measurements - these
can be single-button events on the HP unit.
Even offsetting
Not sure if anyone posted this here yet, but Abracom has a very low noise
(7nV/RtHz at 1KHz) power source for VCO's etc, with various outputs. It's
sold on DIgikey or Mouser I think.
Here is a review of that unit:
_http://jaunty-electronics.com/blog/category/reviews/_
I think it's supposed to work up there.
Cocom limits used to be 50,000 feet and 1000 knots if I am not mistaken.
Most GPS will likely support those Cocom limits even if they state something
like 2000 meters max altitude etc.
A commercial flight should certainly work, besides the problem of
Or a good battery as a source for the regulators as discussed in this
thread already.
It's quite nice to have all the different Voltages available at the same
time, with up to 200mA.
bye,
Said
In a message dated 1/31/2013 13:12:33 Pacific Standard Time, li...@rtty.us
writes:
Hi
For
How to check if a GPS works at 60,000 feet: send up a balloon:
The good folks at Duke University sent a uBlox based GPSTCXO up there, and
it worked at max balloon altitude which was about 60,000 feet. The ambient
temperature must have been around -50C up there, and maybe down to -67C
Not sure if these were properly answered yet, but the ublox Windows
application is a great way to dissect most any NMEA sentence into all it's
components, check for consistency, graph stuff, and check for PVT info.
We use it with anything that generates NMEA sentences, it works great. Of
Wish I had more time to play with this setup.
How about fellow time nuts spend some time and present similar test data on
their OCXO's to compare?
I was interested in the 1s to 100s ADEV, and my runs were from 8 minutes to
20 minutes, certainly enough time to capture data for 1s to 100s
Not sure about that, if you look at the frequency plot after ~20 minutes in
moving air the frequency was still extremely close to 10.00MHz.. to
within 1E-011 of 10MHz. This is a free-running 10811.
Compare that to the plot of the OCXO I had sent out some hours ago when it
was running
Hi Tom,
but they could have achieved the same exact result by using scientific
notation such as:
2.3E-010
or:
2.30E-010
or:
23E-011
to note the higher internal resolution in the later case.
I realize that one can easily parse these raw outputs, if one can write
python or C etc
Hi anonymous,
the 53132A only does that for a couple of nanoseconds. Then it jumps to a
stupid value such as:
0.004 us
-0.002 us
0.999,999,993 s
It get's even better when the counter decides it doesn't have enough
resolution in frequency mode:
2,3** u
Absolutely horrible to parse,
Stu,
a fan is about the worst thing you can do for your Z3805 it will
significantly worsen the stability of the output frequency. The oven inside
does get
warm, that's why it is an oven :)
The power consumption will go down once it heats itself up, the unit is
designed to work without a
Hello Tom,
the GPS noise dominates for typical double oven OCXO's where the tempcos
are very small (say below 5E-012 per degree C).
On single oven units, the tempcos are typically 50 to 200 times larger, and
thus the required EFC change over temperature is also that much larger.
If I am
David,
The NXP LPC932 processor series are very cheap and small, and we got very
excited to see timers running at up to 32MHz internally if I remember
correctly.
Then setting up a test system we noted that the timer can capture with
32MHz resolution which is good enough for a low-cost
Hello,
metastability is not an issue in this type of application, nor can it be
avoided since we have two different clock domains.
It would only shift the capture point by one counter clock cycle back or
forth if the edge happens right on the transition point. At that point we
have 50%
Good list Bob,
many people underestimate what it takes to make a working, commercial
GPSDO, especially one that has to perform in volume and beyond a single well
taken care of unit in a Ham shack.
Once you have taken care of items 1) and 2), the real work begins. This is
where our
Hans,
would mixing your 125KHz with a 2.5MHz or 5MHz low noise reference to get
it into a range that the analyzer can read work?
You could use a system like the Miles timepod phase noise analyzer, a
mixer, a 5MHz low-noise reference, and a low-pass filter to make use of the
500KHz lower
Hi Tom,
there are two that sound very interesting: the M12/uBlox one and the
Time-Nuts one :)
Do you have any other info, or could you give us a 1 minute overview of
what was shown please?
I also heard that there were scheduled to be more CSAC type papers, but
they did not get DARPA
Didier,
Oh, ok that makes sense, but that is a non-standard output, so not sure
that you want to use such an output as a sample case for generic applications.
Alternatively maybe rename the page to Trimble CMOS-output Coax Cable
Impedance Matching to make that clear.
It would be better
Hi Didier,
yes, if you put a 50 Ohm termination at the far end all looks good, but you
are still driving a 91mA DC current through the cable during the high
times, and that will have rippling effects on the driver board by loading the
5V power supply down with a 1Hz period.
And if you
There is one calibration that can only be started by a GPIB command. I ran
into that, my unit constantly said something like xxx calibration
required or similar during power on. No way to do it with the front panel
buttons.
It is easy to start that cal using Visi, or via sending a GPIB
John,
thanks for your email, I am replying to Time Nuts as well as there is a lot
of knowledgeable folks here that can help.
In terms of a GPSDO tutorial, take a look at the HP papers linked on the
JLT website under the Links Of Interest and Related Whitepaper sections:
No problem, happens to me too some times,
usually the 10MHz Sine should be loaded with 50 Ohms, and the CMOS/TTL 1PPS
pulses should be run open-ended (1M or higher)..
I say usually.. because there are cases where proper termination is
critical such as LVDS 1PPS outputs.. and where the
I think the Z3801A has the 6 channel receiver, the Z3805A seems to have the
16 channel GPS.
Otherwise very similar I think.. both have the 10811 DOCXO, and very
similar looking PCB's..
Rick, do you know of any other differences by any chance?
Said
In a message dated 10/14/2012
Hi Edgardo,
I think the Z3805A and 58503A are identical, except in the rubber bumpers,
maybe the power supply voltage setting, and the ID string..
I don't really care, the three units I have perform much better than
anything else I have, so that satisfies my requirements..
In fact one of
Very nice plot Tom!
Did you thermally insulate the CSAC to get this kind of performance?
bye,
Said
In a message dated 10/3/2012 09:24:54 Pacific Daylight Time,
t...@leapsecond.com writes:
Many thanks and for all of your help thoughts over the years. I'll look
forward to the day and
Yes, very easy:
1) calibrate the internal 100MHz vectron OCXO using a small screwdriver,
this is not really critical though as the unit does not really function as a
frequency counter.
2) Calibrate the power supplies for proper voltages if necessary with same
screwdriver, I found that is
Thanks much Didier!
Those are kind words for the JLT team :)
bye,
Said
In a message dated 10/2/2012 14:28:13 Pacific Daylight Time,
shali...@gmail.com writes:
Well Said, it looks like you have been busy!
Congrats for an amazing product.
Didier
Sent from my Droid Razr 4G LTE
Hello Paul,
thanks much for the feedback!
Yes, we think we have identified a nice combination of oscillators, GPS,
and firmware that seems to work pretty well. The GPSTCXO units cannot be
compared to a lower cost $150 Thunderbolt in terms of phase noise or stability
of course, and they
Fellow Time Nuts,
in the last week we had more than 50 emails concerning Fedex versus UPS
shipping and how to package something, now we have a similar number of emails
about LED lighting.
I hope we can end this thread soon, or move it to another discussion group.
I for one am getting
Hi M.
welcome to the world of GPSDO optimization, one thing you will find is
that there never is a time when there is no chance to improve something :)
On the 1PPS sawtooth correction, the usual convention is for the following
1PPS.
The easiest thing to do rather than trying to guess
Hello Edgardo,
glad you received them well, and within 48 hours from China! Hopefully
they will work as well for you as for me.
I noticed that some of the 60Hz/120Hz artifacts can come through the power
supply into the 10MHz, so pick a power supply that has a case-ground
connection, not
Charles,
maybe I did read your email wrong, I apologize for that. To me it came
across as negative toward the seller and the listings, and it seems this is
not how it was meant, my appologies.
Bye,
Said
In a message dated 9/8/2012 23:05:30 Pacific Daylight Time,
Hello Robert,
your question is like asking which car you should buy, or which airline you
should fly :)
Everyone will have a different answer.
But I do not recommend the Thunderbolts, it's a crab-shoot with them
(different versions have different performance, the new ones are actually
Robert,
my bad, that seller offers 58503A units based on both Z3801A and Z3805A.
The latter has a 16 channel GPS receiver, so seems to me much more desirable
than the Z3801A. $50 difference. I have been testing the latter, not the
former.
bye,
Said
In a message dated 9/7/2012
Hi Edgardo,
they work well for me, look brand-new, and came with power supply, rs-232
cable, and antenna. I think it's a 5V antenna. The unit had about 37000 on
the lifetime.
The seller has close up photos, that's what the units look like. I plugged
in the power, ran GPSCon to start an
Hi Jerry,
I am not familiar with those, sorry.
The only complaint I would have about the 58503A units I have is that they
have a bit of power supply spurs at about -130dBc. Running them from
batteries would probably take care of that. Otherwise they work great for me
and
provide both
Dave,
that depends on which uBlox the unit supports. There are basically three
different sizes: AMY, LEA, and NEO. They also sell chip-sets, but only to
very large volume customers.
Any of the uBlox-6 will be excellent, the choice will depend on
form-factor, and also if you need a
There are some drawbacks to this type of SC-cut MCXO I would think, and it
could possibly be replaced by a much higher performance Symmetricom CSAC,
probably at a lower cost and higher availability:
* Q-tech MCXO is ITAR controlled, CSAC is not
* MCXO has 20ppb over temp stability, CSAC has
Hello everyone,
please send suggestions for the following new product we are working on:
Trimble recently announced that the Mini-T is end of life, and is giving a
last time buy of August 1st 2012. It does not seem that Trimble plans to
offer a replacement unit. The Mini-t enjoyed a
Hi guys,
thanks so much for all the great suggestions on how to make this product
better!
Yes, cost targets are a very important goal here, and we are looking into
adding options that make sense for most customers and don't add excessive
cost or delay to the schedule. We definitely will
Yes, I am sure, depends on the firmware revision and configuration
settings. Don't want to name any names here though. Secondary firmware can
detect,
and prevent this behavior once you know it exists, and what makes it
happen.
That's part of what makes the difference between an NCO and a
FEI did not own Morion, they owned a number of shares.
Some time ago the Russian government forced them to sell all, or almost all
of their shares to keep Morion fully Russian-owned.
Unfortunately they are not easy to deal with on a commercial level (to put
it into objective terms), and
Jerry, Chris,
it's all relative, while the Lpro may be a good Rb standard, it's phase
noise is not that good really. You list:
-96dBc/Hz @ 10Hz, -138dBc/Hz @ 100Hz, -152dBc/Hz @ 1KHz offsets
For the Lpro. The new Jackson Labs Technologies LN CSAC GPSDO with SC-cut
phase noise and
Yes, but the point is to not use end-termination for all the reasons
mentioned by others in this thread, such as massive spike in power consumption
once per second, over-voltage spikes if the termination is faulty or
missing, higher ADEV due to power supply modulation, etc etc..
Your test
Not really, your setup requires all inputs except the very last one to be
high-impedance to work, and to have a trigger point of 1.25V as well to work
properly (when used with a proper 50 Ohms source). So no difference there.
So it doesn't make any difference, since the same exact inputs
Mike,
Attila is trying to explain that the leading edge is not what we are
concerned about in this thread (its subject to discussion in other email
threads), it is the effect of what follows after that leading edge, and
propagates
down the power supplies to cause side effects that is
QED: here is a phase noise plot of a 200ms 1PPS pulse showing up in the
phase noise spectrum of a 10MHz source (at 1Hz to 10Hz offsets) because the
unit was providing a 100mA current pulses into the cable, and power supply
modulation of the 10MHz output happened inside the unit.
The pulses
Forgot to mention,
on this list we are often concerned with noise floors of -170dBc or lower,
and stabilities of 1E-013 or lower.
At that level, your scenario of stepping into the room and turning on the
light will likely cause a measurable effect just because of the mechanical
vibration
Yes, you are right of course. My bad. This should have been written as:
The Thunderbolt has less than 5 Ohms output impedance, so if you get a
reflection coming from the cable stubs or non-end-terminated cable back into
the Thunderbolt, then you get ringing on the cable because the
Hi Rick,
one reason why we happy blink at 1/2Hz :)
There are other offendors as well, such as the processor and GPS going
through the hoops once per second, but the 100mA surge from the 1PPS output
driver trumps all else.
bye,
Said
In a message dated 5/15/2012 16:44:08 Pacific
I met Jenny in 1987 - not that skinny at the time :) That was after she
sold the company already.
In a message dated 5/15/2012 16:41:34 Pacific Daylight Time, b...@iaxs.net
writes:
Jenny Craig?
___
time-nuts mailing list --
Hi,
here is a very nice and easy to use online calculator for doing exactly
this:
_http://jittertime.com/resources/pncalc.shtml_
(http://jittertime.com/resources/pncalc.shtml)
bye,
Said
In a message dated 5/11/2012 09:17:30 Pacific Daylight Time, li...@rtty.us
writes:
Hi
Be very
Hugo's idea of using a Sat dish to zoom in on a WAAS Sat as discussed in
the below paper is quite brilliant I think, and it seems one should be able
to make use of it by disabling the GPS sats (via mask angle for example) in
receivers that support WAAS, and that are used in position hold
Hi Holrum,
how do you re-configure the SMT unit? Using Trimble GPS studio?
Thanks,
Said
In a message dated 5/9/2012 15:17:21 Pacific Daylight Time,
hol...@hotmail.com writes:
I have it running now. It turns out that the units from fluke.l come
shipped with TEP format messages
Ok,
I figured out that the unit fluke.l sells is running firmware to emulate
the Motrola M12+ receiver or similar. So WinOncore 12 does work, and I can
get the following receiver ID:
COPYRIGHT 2008 Trimble Navigation Ltd.
SFTW P/N #
SOFTWARE VER # 0.03.0
SOFTWARE REV # 00
SOFTWARE
The first problem is, I didn't even know that was the command set the unit
had, the @@Cf looked familiar though. I wasted an hour trying to get the
Trimble application to work, until I tried WinOncore12 and the unit
responded.
Can't use TeraTerm to send commands, and the user manual
There is the problem: I used the Trimble GPS Studio application that was
posted here yesterday, that does not support the TEP protocol.. Will try with
GPS Monitor..
Is the TrimbleMon available somewhere safe on the web? Can't seem to find
it with Google.
I got it working with Oncore12,
Guys,
this thread and the un-countable emails it has generated so far is the
exact type of discussion that TVB just sent out an email about that should not
be on time nuts.
bye,
Said
In a message dated 5/7/2012 16:00:54 Pacific Daylight Time,
mbla...@satx.rr.com writes:
Wow! $1260
No necessarily.
It could also mean the 5370B likes the output signal of the 10544 fed
internally better than the other two, maybe due to a higher signal level or
less noise in the internal PLL bandwidth?
You could verify this by feeding in the 10544 into the front jack while the
10811
Incorrect, the UTC offset should be sent in the Almanac, the Almanac
having a period of 12.5 minutes max. Not one hour. It should take no more than
12.5 minutes to get the UTC offset when sats are properly being received.
bye,
Said
In a message dated 5/1/2012 11:45:06 Pacific Daylight
Hello Mark,
you could connect the Fury 1PPS output to the 1PPS external sync input of
the PRS-10 Rb and let is self-discipline to GPS. Set the Fury 1PPS jumper
JP4 to raw-1PPS (pins 2 and 3), and that will make the Fury GPSDO generate
the raw 1PPS signal from the Motorola GPS receiver
Make sure to buy the quadrouple shielded 75 Ohms RG-6 cable from Home Depot
etc, it's much better than the standard single or double shielded RG-6 and
works wonders for GPS signals, and it's quite inexpensive.
Impedance mismatch loss can be neglected, and long cable runs can be made.
bye,
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