Well, a big one will be in 2017 when all our Tbolts roll over.I have
included some code in the next version of Lady Heather to compensate. If it
detects a year from the unit before 2015, it converts the date/time to Julian,
adds 1024 weeks worth of seconds, and then converts the
Hi Rick:
Any suggestions for a circuit with better performance. Purpose will be a
external standard for a frequency counter.
-=Bryan=-
Date: Mon, 4 May 2015 21:09:51 -0700
From: rich...@karlquist.com
To: time-nuts@febo.com
Subject: Re: [time-nuts] Divider circuit for Rubidium Standard
On Tue, 5 May 2015 17:58:06 -0400
Bob Camp said (inter alia):
Ok, all of these receivers are designed to work with an amplified antenna.
The typical antennas have between 20 and 30 db of gain.
They allow a cable loss of ~ 10 db between the antenna and the receiver. A 3
db splitter would
That's one of the reasons I was considering a re-spin of the board using a
better ZCD solution.
Dave
-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Richard (Rick)
Karlquist
Sent: 05 May 2015 05:10
To: Discussion of precise time and frequency
The Phase noise floor (~-143dBc/Hz @ 1kHz) of the 10MHz output of that divider
is about 17dBc/Hz higher than either the LTC6957-4 (demo board) or the
Holzworth HX2410 (both ~ -160dBc/Hz @ 1kHz).All measured with a 10MHz +14dBm
input signal.For offsets below a few Hz shielding of the circuitry
brian.ing...@systematicsw.ab.ca said:
GPS provides only the current UTC offset from GPS time, which could be made
available via a custom vendor message, or derived from the difference
between messages which provide UTC and messages (e.g. $GPZDG) which provide
GPS time.
I think it's more
Wenzel has published the schematic of an excellent squaring circuit. I
don't have the URL for their version handy, but I used it (with a couple
of mods) in the TADD-2 and TADD-2 Mini designs. You can see the
schematic in the T2-Mini users guide at
On 5/6/15 12:53 AM, John Marsden wrote:
Ok, I only ask becuse there seemed to be a big thing about LHCP quad helix
antennas - even to the point of seein an article showing how to 'unwrap. a RHCP
Q-H, and rewrap it 'inside-out' to change the polarisation to LHCP.
I'm seriously considering
Hi Pete,
Yes, we are very fortunate that a fellow time-nut took the time to test a TBolt
with a GPS simulator:
https://www.febo.com/pipermail/time-nuts/2014-September/086664.html
He also reported that the 1 PPS and the 10 MHz were undisturbed by the
rollover. Yes, the date/time gets set back
Quite a good thread.
The old rollover is a real pain in the Especially on the old receivers
circa 1990s.
Whats useful is the method for calculating the week mentioned. Granted
there are tools online that help. But the math associated with reversing
the date now is clearer using the Julian
On Wed, May 6, 2015 at 3:39 PM, Tom Van Baak t...@leapsecond.com wrote:
Hi Pete,
Hi Tom,
Yes, we are very fortunate that a fellow time-nut took the time to test a
TBolt with a GPS simulator:
https://www.febo.com/pipermail/time-nuts/2014-September/086664.html
That's the link I included in
Whats useful is the method for calculating the week mentioned. Granted
there are tools online that help. But the math associated with reversing
the date now is clearer using the Julian date. May tinker in excel as I
think there are date macros and such available.
The output needed for the old
On Wed, May 6, 2015 at 6:48 AM, Mark Sims hol...@hotmail.com wrote:
Well, a big one will be in 2017 when all our Tbolts roll over.I have
included some code in the next version of Lady Heather to compensate. If it
detects a year from the unit before 2015, it converts the date/time to
t...@leapsecond.com said:
The hard part is understanding when the GPS receiver fails and when to apply
the 1024 week correction, or not. This is made difficult or impossible if
the receiver does not give you internal information or if you do not already
have external information (like an
Hi
On May 5, 2015, at 10:32 PM, Tom Van Baak t...@leapsecond.com wrote:
Don't think it's _that_ much code though. There's some open source ACM date
algorithms, and it would be easy enough to implement a quick and dirty fix,
adding a number of days offset, while the rest of the algorithm is
Hi
On May 6, 2015, at 3:53 AM, John Marsden og...@live.co.uk wrote:
On Tue, 5 May 2015 17:58:06 -0400
Bob Camp said (inter alia):
Ok, all of these receivers are designed to work with an amplified antenna.
The typical antennas have between 20 and 30 db of gain.
They allow a cable
I had this happen with my S250. It hangs during boot with the spinning
hourglass stopping, right?
The problem ended up being that the processor module had come slightly
unseated. The initial boot messages on the display are independent from the
functioning of the processor module.
Thanks,
David
I worked with the Microsemi boxes at my previous employer. If you suspect
it's the CF, there should actually be two in there. You might be able to
revive it by taking the cards out, making backups with dd, and flashing out
to new cards. This might take some trial and error (definitely preserve
Hi
A standard input on a frequency counter is not a very demanding thing in the
hierarchy of
TimeNut signals. You can drive any of them with some pretty simple logic gate
based
circuits. No need to spend a lot of money.
Bob
On May 6, 2015, at 2:52 AM, Bryan _ bpl...@outlook.com wrote:
Hi
My personal S300 died last month but otherwise I've fielded them in hot,
cold, dusty, wet, and dry environments and they seem to keep going.It
passes the initial self tetst but won't fully boot. I suspect CF card
failure. Microsemi won't talk to me without an active support contract.
Due to
So, yes, our old TS2100's suffered the 1995 bug over the weekend like all of
the others in the world. Kludged into working for the moment using 1PPS and
two units.
I do need to buy a couple replacements, good time is critical around an
observatory, looking at a $16K purchase order. We have
Hi Pete,
I didn´t test the transition - I just entered a few dates
well after the rollover. After locking, the phase of the 10
MHz output was stable against the phase of the 10 MHz REF
out of the signal generator I used for testing, which was
what I expected. The 1 PPS looked reasonable.
Andrew Cooper kirjoitti:
We also ran into the TS2100 1995 bug this weekend.
For us the consequences are a bit more severe...
So this is happening already.. Didn't notice this because have been
using PPS from Thunderbolt to keep the TS2100 in time. It failed with
leap second already in
Mark Sims kirjoitti:
People using Tbolts for things like NTP servers will have to implement a
similar fix...
I'm pretty sure that many GPS based NTP servers will also fail. For
example I have TymServe 2100 and it fails already with leap second
handling. Just now the integrated GPS cannot
Good, you understand my point. You need external information and That
won't solve the problem forever and oh, well, yeah, duh, just rebuild and
reinstall the fixup software anytime there's trouble in the future.
To me this is replacing a broken GPS receiver algorithm with a broken
Arduino
Hi Hal,
Why is that so hard?
Depends if you want a quick hack (easy) or a solid solution (hard).
If I understand things correctly, the time (UTC) is correct because the GPS
receiver is using the current GPS-UTC offset. But the date is off by 1024
weeks. (or some multiple of that)
You
On 2015-05-05 11:32, Alan Ambrose wrote:
It's not that simple. First, it's not 20 years, but 1024 weeks (19.6 years).
And not UTC weeks (which may have leap seconds) but GPS weeks (which do not,
and are always 604800 seconds long). etc
Don't think it's _that_ much code though. There's some
On 2015-05-05 11:58, Tom Van Baak wrote:
And now I guess we can't blame Trimble either since their 15-year old Ace
documentation [1] says:
ACE III GPS
System Designer Reference Manual
Part Number: 41265-00
Revision: A
Date: June 2000
Firmware: 8.08
Hi
Once you dig inside the TS2100 to add a CPU board between the GPS and other
guts, you have reliability issues as well…..
Bob
On May 6, 2015, at 5:35 PM, Bob Darlington rdarling...@gmail.com wrote:
My personal S300 died last month but otherwise I've fielded them in hot,
cold, dusty, wet,
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