We have a number of these upgraded units from China, ours have the double oven
10811 and they are awesome. Great ADEV and great PN and very little spurs. In
fact we use them as house standards for our TimePod and TSC5125A.
They are upgraded to a nice desktop case and the 58503A firmware.
They
The 58503A we got have much better ADEV and PN than what was posted recently on
the Lucent boxes. TVB has many plots of the Z3801A on his website - same box.
They used to be $399 on eBay, now likely $500 or more, but you get what you pay
for..
Sent From iPhone
On Nov 27, 2014, at 16:14, Bob
of the 3801 and KS boxes are pretty darn close.
Bob
On Nov 27, 2014, at 6:45 PM, Said Jackson via time-nuts time-nuts@febo.com
wrote:
The 58503A we got have much better ADEV and PN than what was posted recently
on the Lucent boxes. TVB has many plots of the Z3801A on his website
:)
Sent From iPhone
On Nov 26, 2014, at 9:20, Didier Juges shali...@gmail.com wrote:
Said,
Your drawing looks better than those by Bob Pease, and he was never
embarrassed by his :)
Thank you for your extensive contributions to time nuts
Didier KO4BB
On Tue, Nov 25, 2014 at 7:28
Jim,
A double tragedy. I was working with Jim Williams on one of our designs a week
before he passed away. Then Bob crashed his car coming from Jim's funeral
(grief?) and died too.
Two of the greatest analog minds lost within days.
Bye,
Said
Sent From iPhone
On Nov 26, 2014, at 9:34, Jim
Charles,
The increased current for the driver will cause heating near the crystal in
both the CMOS driver and the 3.0V LDO as the LDO has to convert the excess
voltage into heat. This may or may not affect the crystal.
One could certainly try, this is why I initially said its certainly
Dave,
Exactly.
Sent From iPhone
On Nov 25, 2014, at 7:34, Dave Martindale dave.martind...@gmail.com wrote:
The 20 MHz output should be OK, since it is series-terminated with 50 ohms
at the source and the buffer can source enough current. The driver sees a
100 ohm load (50 ohm resistor in
We evaluated a Glonass unit for 1PPS and it was really quite bad. Unless you
are near the poles or get jammed a lot I would not see much advantage..
Sent From iPhone
On Nov 25, 2014, at 15:10, Bob Camp kb...@n1k.org wrote:
Hi
I think it’s more a supply and demand thing right now. There
It does output two proprietary messages, one from Skytrack, but not sure I
would use the Skytrack application due to the low information content of that
message and the instability of the Skytrack app. The uBlox app lets you view
the two proprietary messages too and is stable. Everyone can use
Paul,
You can listen to PJLTS on the USB and grab the Skytrack NMEA in TTL format
from pin 13 of header JP1 at the same time..
Sent From iPhone
On Nov 25, 2014, at 15:37, Paul tic-...@bodosom.net wrote:
On Tue, Nov 25, 2014 at 6:03 PM, Joseph Gray jg...@zianet.com wrote:
Yes, I know
Bob,
Its not the 1PPS that would be suffering, its the 10MHz that will have all the
1Hz and its harmonics making the PN graph look ugly..
Agree with you that the regulators cost zip these days and using individual
buffer ICs and regs is the best way to go.
Bye,
Said
Sent From iPhone
On Nov
months ago
here in detail..
Sent From iPhone
On Nov 24, 2014, at 5:32, Dr. David Kirkby (Kirkby Microwave Ltd)
drkir...@kirkbymicrowave.co.uk wrote:
On 24 November 2014 at 03:44, Said Jackson via time-nuts
time-nuts@febo.com wrote:
On the 20MHz units there is already a strong buffer
Jim,
Bobs suggestion is good; look at for example the LT3060 for something that
needs less than 100mA.
Glad your antenna is working well. What C/No numbers is uBlox indicating?
Bye,
Said
Sent from my iPad
On Nov 24, 2014, at 16:28, Bob Camp kb...@n1k.org wrote:
Hi
The Linear LT1764 is
Jim,
41 to 50dB is great.
The height difference may be MSL to GPS height?
Bye,
Said
Sent From iPhone
On Nov 24, 2014, at 18:39, Jim Sanford wb4...@wb4gcs.org wrote:
Said:
I'm seeing C/No numbers between 50.0 and 41.0 for the green birds. I'm
seeing 27.0 to 42 on the blue birds. Not
Bill,
Check out the Ettus Octoclock. Its probably without competition at their $900
price point:
https://www.ettus.com/content/files/Octoclock_Spec_Sheet.pdf
Its very compact and quite useful. Is it the lowest noise amp ever built? No.
But its state of the art for low-cost distribution of
Tom,
From the looks of the plots these may be from the first proto unit with early
software no? Also was this with the indoor GPS antenna setup?
The production units with outdoor or windowed' antenna should have
significantly improved average performance from the first unit and its early
GPS
Charles,
Any buffer options added to the board would have caused either additive phase
noise or added power consumption, and possibly yet another low noise LDO to be
required.
On the 20MHz units there is already a strong buffer that can drive 50 Ohms
terminations so adding a buffer in front
Hi Paul, Jim, David,
Let me address all your emails:
Glad you got your boards. $50 in overseas additional charges from your post
office sucks!
Some hints for experimenting from what I have learned:
You definitely want to build a 50 Ohms buffer for the 10MHz boards and the
synthesized outputs
Nigel,
CC'ing time nuts..
R2 and R3 are stuffing options, see the schematics in the user manual.
Typically you don't have to solder anything. The default is set for the
low-noise 3.0V to be fed to the DIP-14 tcxo for best performance.
On your question on removing the SMT Tcxo, this is not
Bob, how is the PN?
Glad that after 100s of emails about the serial port on this unit finally
someone is finally posting some real data.
Still surprised that the ADEV is not as good as the 58503A units I got on eBay.
Sent From iPhone
On Nov 17, 2014, at 8:22, Bob Camp kb...@n1k.org wrote:
Sometimes eBay limits the number of units a vendor can list at any time to
limit their financial responsibility.. Happened to us.
Sent From iPhone
On Nov 17, 2014, at 12:14, Bob Camp kb...@n1k.org wrote:
Hi
It’s pretty simple. Put X pieces in your cart and see what happens. At the
Correct on all counts Bob.
My two 58503A units from China are great for both ADEV and PN measurements,
better than anything else I have as a combo (I have Wenzel ULNs for even lower
PN testing but they don't have any usable ADEV). I also have a costly BVA and
it can't compete against the HP
Thanks Paul, Glad you like it!
On the PSTI question from earlier: the GPS vendor snuck two additional fields
into the PSTI message on their last fw update. The two new fields are as
follows:
Position Standard Deviation Threshold
Calculated Position Standard Deviation After Self-Survey
The
Whatever the source for that signal, it may explain why all our wwvb clocks
have had receiving troubles over the last weeks syncing up here in NV...
Sent from my iPad
On Nov 14, 2014, at 6:10, paul swed paulsw...@gmail.com wrote:
OK everyone. I am sorry I left my 60 Khz transmitter on in
The premise of higher than normal click speed is false in the article too
because the complex NOR gate is slow with that many inputs, and its tpd needs
to be added to the Tsu and Tco of the flip flop chains, as well as the pcb
propagation delays through the worst case trace..
It would have
to in excess of 100mhz, some vendors as high as 120mhz, at ordinary
temps. I will have to look, but I might have a tube or two of them in the
basement. I know I have most of the other 74F.
On Nov 7, 2014, at 23:20, Said Jackson via time-nuts time-nuts@febo.com
wrote:
Joe,
This puppy can
Hal,
That means in a divide by 5 you cant even get close to 125MHz even if the
74lvc163 is rated at 200MHz count frequency. Very good point.
I used to use ABEL with DataIO programmers back in the day, Abel is now
licensed by Lattice and I think they still support the old 16V8 and 22V10
Messineo francesco.messi...@gmail.com
wrote:
Sorry if I hijack the thread...
On Sat, Nov 8, 2014 at 5:20 AM, Said Jackson via time-nuts
time-nuts@febo.com wrote:
Joe,
This puppy can go to 166MHz over temp and has standard 100 mil pin spacing
if you put it into a socket: ATF16V8C
I
That part is limited to 95MHz over temp. Not suitable for commercial designs,
but probably works just fine for a one-off..
Sent From iPhone
On Nov 7, 2014, at 19:37, Joseph Gray jg...@zianet.com wrote:
Looks like I can get the 74AC161 in DIP from Mouser. Thanks to everyone for
the
Joe,
This puppy can go to 166MHz over temp and has standard 100 mil pin spacing if
you put it into a socket: ATF16V8C
I have not used PALs since 1992 but I used to be extremely fond of the 16R8 and
22V10 types back then.
This is a 16V8 that will do your divider in no time:
Same here Nigel,
However I seem to have gotten about 200+ emails about a Lucent GPSDO over the
last couple of days so something is working, or the list simply got inundated
with Lucent KS-24361 related emails.
Bye,
Said
Sent from my iPad
On Nov 4, 2014, at 7:12, GandalfG8--- via time-nuts
Karen,
PRS-10..
Sent From iPhone
On Oct 26, 2014, at 10:46, Karen Tadevosyan ra3...@mail.ru wrote:
Hello All,
Can I have your recommendation regarding a choice of 10 MHz rubidium source
(available now on eBay like FE-5680; LPRO-101; LPFRS; FRS etc.) as a
reference signal for my
Poul-Henning,
I mentioned yesterday about integrator windup, this problem is similar but
happens even without any I term present:
The problem is that the ocxo maintains its frequency even though the EFC
control voltage is changing. Thus phase error is accruing making the efc larger
and larger
Hi Hal,
This behavior is called hysteresis and it is related to vendors, and related to
the chips used (or varactor diode) inside the tcxo/ocxo. It is so subtle that
most vendors are not even aware that their oscillator is doing it. Some vendors
have product lines that do it and others that
Burt,
Great insight thanks. You nailed it: out with the old oscillator and in with
one that doesn't have that problem.
Btw the mechanical tuning issue you mentioned is essentially the same exact
problem: even the slightest turn will make the frequency jump too high or too
low. It can drive
Paul,
I will answer you offline.
Guys please don't post items like this that aren't really of interest to all
the others on the list.
Thanks,
Said
Sent From iPhone
On Oct 20, 2014, at 13:41, paul swed paulsw...@gmail.com wrote:
Said
Having some fun reading your posts on time-nuts.
I
Bob,
You are on the right track!
Large changes in EFC can cause hysteresis, meaning you go back to an initial
voltage but the crystal does not return to the exact initial frequency. It can
also create dead bands in the efc vs frequency curve.
Hysteresis can cause integrator wind up as the
Thats exactly right Bob.
By the time your ocxo jumps to catch up to the efc voltage, you have
oversteered, then the process starts in reverse and the ocxo jumps in the
opposite direction.
The result is a phase jumping up and down.
You want a crystal that reacts to xE-012 changes in EFC
Thanks much Alan!
It would be funny if it wasn't so serious. Guys let me know (but please without
copying the entire list!) if Ebay is not working out for you and we will find a
way..
Bye,
Said
Sent From iPhone
On Oct 18, 2014, at 13:34, Alan Melia alan.me...@btinternet.com wrote:
Said I
Hi Bill,
I think it makes perfect sense. But I have no idea how the units' loop
stability would be with the 10811. That kind of testing is on the plate.
You would preferably set the OCXO to a nominal tuning voltage of 1.5V using the
mechanical adjustment, then let the LTE Lite do the rest.
Tom,
Nice performance. Wish we could get that today! My fairly modern BVA is nowhere
near that stability.
If you open up a brand new DOCXO you will see a crystal designed in the 70's
and an oscillator circuit designed sometime in the 30's or 40's, maybe updated
to a more or less modern
Hal,
An ocxo has two effects that cause a frequency change after power on: heater
stabilization and crystal retrace.
Heaters usually stabilize quickly (1 - 2 minutes for DIP-14 ocxo, 7 to 10
minutes for typical eurocan docxo's) and then a. ~30 minutes soak until the
ocxo starts following
Said,
Could you point us on something describing that ? What kind of
digital processing do you think about ?
Cheers
Stephane
-Message d'origine-
De : time-nuts [mailto:time-nuts-boun...@febo.com] De la part de Said
Jackson via time-nuts Envoyé : dimanche 28 septembre 2014 07:50
À
Mark,
In the analog domain you can probably do a PLL with a 1Hz loop BW. Using a PLL
chip like ADF 4002 or similar. This means all the nasty noise from the NEO will
taint your PN up to 20Hz or more, very significantly close-in. If you don't
care about noise (jitter) below 100Hz then this is
Hi everyone,
Thanks so much for your interest in our new LTE-Lite GPSDO.
I got something like 40 or more email inquiries so far! Its been a fantastic
response, thank you everyone.
We will try to get everyone's emails and questions answered next week, please
hang in there, and sorry that I
Hi Didier,
You showed the effect of standard end-termination and no end-termination both
while driving the cable with a mis-matched low signal source impedance. These
are the same type of plots that Tom posted a link to last week.
The interesting plots will be when you set R1 to match the
Hi Hal,
I think its a slow driver, and a complex output impedance, not necessarily a
weak driver.
I have a Tbolt hidden somewhere and would need to dig it out. My 30 foot cable
disappeared though, so I need to buy a new one :(
On the small hump, i don't think that is a reflection. The signal
Hi guys,
Tried to bring my point across, but I guess I failed to do so properly.
What happens after the edge is very important because what happens after the
edge settles is up to 100mA DC current is flowing through all the coaxes AND
your building ground.
Pumping ~5V into 50 Ohms
Hi Stephanie,
Welcome to the list!
We designed a 1GHz crystal LO for PLLs (the ULN-1G) using an off the shelf
miniature 500MHz crystal oscillator which is run at 3 rd overtone internally
then using a diode doubler and a steep bandpass filter using several Mini
Circuits ceramic filters and a
Peter,
You don't need nor do you want a 50 ohms end-termination on a series-terminated
50 ohms coax cable.
This has been discussed here extensively before, please check the archives.
Your last sentence is not correct.
Also, you are running into your scope's BW limit if you are measuring a 4ns
Ok, did the math, a 4ns risetime should be ok on a 200MHz scope.
You likely won't see the oscillations and reflections visible in Toms 58503A
plots for example, they are faster than the risetime.
Bye,
Said
Sent From iPhone
On Sep 14, 2014, at 8:35, Said Jackson via time-nuts time-nuts
risetime.
Isn't the ringing frequency simply a function of the length of
the coax? Isn't it the price you pay for mismatched impedances?
Pete.
-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Said
Jackson via time-nuts
Sent: Sunday, September
.
-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Said
Jackson via time-nuts
Sent: Sunday, September 14, 2014 11:36 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Correcting jitter on the 1 PPS
signalfromaGPSreceiver
see the oscillations and reflections visible in Toms 58503A
plots for example, they are faster than the risetime.
Bye,
Said
Sent From iPhone
On Sep 14, 2014, at 8:35, Said Jackson via time-nuts time-nuts@febo.com
wrote:
Peter,
You don't need nor do you want a 50 ohms end
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