Hi,
While reading up on oscillator circuits i stumbled over differential
oscillator structures (see [1] for example). But sofar i have been
unable to figure out what the exact advantages of a differential
oscillator strucutre in general are.
Would someone here be so kind and give me some hints
Hi Attila,
I gather you did not fully read the paper ?
In normal CMOS circuits, the higher the oscillator frequency the higher
the amount of current drawn to reach that higher frequency. So, the two
oscillator system was used to keep time and wake up the higher
frequency oscillator (for
On Sat, 10 Aug 2013 02:39:35 -0700
wb6bnq wb6...@cox.net wrote:
I gather you did not fully read the paper ?
I did, but...
This paper presents a circuit topography that allows the low current
operation at a high frequency (12.8 MHz) thus reducing complexity. This
in turn allows the design
Bob wrote:
For a reasonable standard distribution, you probably want one input
and many outputs. One in / eight out or one in / 12 out are fairly
common. At least the video gizmo we've been dissecting has trouble
past one in / 4 out.
It has 6 CLC409s, each of which drives 3 BNCs, for 18
I wrote:
All of these solutions are for feeding the external reference inputs
of various test equipment, radios, etc., not for buffering and
isolating signals for serious phase noise or ADEV analysis.
By the time you design a PC card and have it made, you are way, way
beyond not a lot of
Hi
If you are buying NPO caps that are +/- 20%, get another supplier….
Bob
On Aug 9, 2013, at 10:27 PM, briana als...@nc.rr.com wrote:
A cap marked 82pf might indeed be 79pf or any value 15-20% either side of the
marked value.
Depends upon what cap type you use. If you really need 79pf,
Hi
On Aug 10, 2013, at 6:29 AM, Charles Steinmetz csteinm...@yandex.com wrote:
I wrote:
All of these solutions are for feeding the external reference inputs of
various test equipment, radios, etc., not for buffering and isolating
signals for serious phase noise or ADEV analysis.
By
Hi
A couple of observations:
1) There are *way* more low stability oscillators out there than high stability
ones. A lot of the papers are focused on applications that are not TimeNuts
grade.
2) There are way more oscillator circuits out there than time to list them.
Given a couple of days,
Hi
It's certainly a good low power approach - if you can fabricate it in silicon.
I'd hate to try to do it with discrete devices. The broad band phase noise
isn't going to be anything great, but that's likely not something they are
worrying about in their system.
Bob
On Aug 10, 2013, at
In message 39433ff7-ba50-4e0c-9f11-992aedcd5...@rtty.us, Bob Camp writes:
A couple of observations:
But you have to admit:
5) Getting into low ppm's at 1 microampere is kind of impressive...
There's nothing about phase-noise, so I suspect that's where
the trade-off is ?
--
Poul-Henning Kamp
On 08/10/2013 12:10 PM, Attila Kinali wrote:
On Sat, 10 Aug 2013 02:39:35 -0700
wb6bnq wb6...@cox.net wrote:
I gather you did not fully read the paper ?
I did, but...
This paper presents a circuit topography that allows the low current
operation at a high frequency (12.8 MHz) thus
Hi
I think you'll find that the low current amps in their schematic have pretty
large 1/f noise.
Bob
On Aug 10, 2013, at 11:04 AM, Magnus Danielson mag...@rubidium.dyndns.org
wrote:
On 08/10/2013 12:10 PM, Attila Kinali wrote:
On Sat, 10 Aug 2013 02:39:35 -0700
wb6bnq wb6...@cox.net
Build it from discrete parts, of course, what frequency do you suggest
to try? 32768Hz, 1MHz? I have nothing in-between...
On Sat, Aug 10, 2013 at 5:04 PM, Magnus Danielson
mag...@rubidium.dyndns.org wrote:
On 08/10/2013 12:10 PM, Attila Kinali wrote:
On Sat, 10 Aug 2013 02:39:35 -0700
wb6bnq
Hi
I suspect that built from discrete parts you will simply have an audio / square
wave oscillator. It's a classic multivibrator circuit….
Bob
On Aug 10, 2013, at 11:13 AM, Azelio Boriani azelio.bori...@screen.it wrote:
Build it from discrete parts, of course, what frequency do you suggest
On 08/10/2013 05:13 PM, Bob Camp wrote:
Hi
I think you'll find that the low current amps in their schematic have pretty
large 1/f noise.
True, but if you wanted to fool around a little and see what it could do.
For the intended application, it's probably good enough thought.
Cheers,
Magnus
Hi
Looking at the picture of the die, I suspect their radio has a VCO on it that
they lock up through a (noisy) low frequency PLL. That would mean they really
don't care a lot about phase noise of the reference.
Bob
On Aug 10, 2013, at 11:43 AM, Magnus Danielson mag...@rubidium.dyndns.org
On 08/10/2013 05:55 PM, Bob Camp wrote:
Hi
Looking at the picture of the die, I suspect their radio has a VCO on it that
they lock up through a (noisy) low frequency PLL. That would mean they really
don't care a lot about phase noise of the reference.
Agree. But I was arguing about looking
Hi
The stability with two active devices will be worse than with one. That's true
of tc, ADEV, and phase noise.
Buffering out of the circuit is problematic for a precision application, so
that's likely to add to the noise as well.
It's a reasonable way to do a cheap oscillator. It's
Hi
Any bets on weather or not they have actually designed a 12.8 MHz multivibrator
that injection locks to the crystal? Pretty hard with discrete parts, but not
out of the question with silicon. You'd have to get their spice (or what ever)
files to figure it out ...
Bob
On Aug 10, 2013, at
Hi:
This is an interesting type of VNA where they independently change the LO and detector DDS clocks to fill in what
otherwise would be nulls thus extending the frequency coverage. 20 minutes into the video they talk about comparing two
Rb sources.
HAMRADIO 2012 DG8SAQ VNWA UK HD (2012)
On 10 August 2013 19:59, Brooke Clarke bro...@pacific.net wrote:
Hi:
This is an interesting type of VNA where they independently change the LO
and detector DDS clocks to fill in what otherwise would be nulls thus
extending the frequency coverage. 20 minutes into the video they talk about
To the Group,
Here is a link of Gerry's update video addressing some of the concerns
expressed here and other places.
http://gerrysweeney.com/10mhz-rubidium-frequency-standard-and-signal-distribution-amp-follow-up/
BillWB6BNQ
___
time-nuts
Some of the GPS clocks think its 26 Dec 1993.
A Z3805A, a Z3815A and 58534A integrated timing antenna all think it's 26 Dec
1993.
What happened?!
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
ma...@non-stop.com.au said:
A Z3805A, a Z3815A and 58534A integrated timing antenna all think it's 26
Dec 1993.
What happened?! ___
Is that off by 1024 weeks? (Looks close, but I haven't checked the details.)
There is a week field in the GPS data
Hal, I can't get it to take, I keep getting E-350 and the time does not change.
Did you unplug the antenna or anything while you changed date?
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf
Of Hal Murray
Sent: Sunday, 11 August 2013
Okay this is what worked for me:
1. Removed power and antenna.
2. apply power with no antenna.
3. send :GPS:INIT:DATE 2007,08,11
4. plug antenna back in.
For some reason if I used the correct date, the Z3815A warped back to 1993.
But I am curious why did this happen today?
--marki
ma...@non-stop.com.au said:
Hal, I can't get it to take, I keep getting E-350 and the time does not
change. Did you unplug the antenna or anything while you changed date?
I don't remember doing anything like that, but it was a long time ago.
I may have told it the date while it was doing a
With the wrong date and time, the GPS should not find almanac data,
so will not lock.
This was the problem caused by the 1024 week roll over problem.
Are we possibly at week 2048??
73
Glenn
WB4UIV
At 11:28 PM 8/10/2013, you wrote:
ma...@non-stop.com.au said:
Hal, I can't get it to take, I
I just checked by Z3801A which is being monitored by SatStat on an old
laptop. Mine is showing the correct date and time.
Joe Gray
W5JG
On Sat, Aug 10, 2013 at 8:53 PM, Hal Murray hmur...@megapathdsl.net wrote:
ma...@non-stop.com.au said:
A Z3805A, a Z3815A and 58534A integrated timing
I have 5 Z3805A and only one had the wrong date.
They all have identical GPS modules and firmware so I don't know why just one
decided to warp back to 1993.
The Z3815A is still stuck at 1993, I can't even set it to 11 Aug 2007. (-1024)
even with antenna unplugged and power cycle.
I mean, Can
With the wrong date and time, the GPS should not find almanac data, so will
not lock.
I don't think that's the right way of describing the problem.
The satellites broadcast on a known frequency, but that gets shifted all over
the place by Doppler. (All over means a big shift relative to
Nope, I tried all the resets I could find, I can set the date right but as soon
as the Z3815A sees a bird, it jumps back to 1993.
How annoying, Anyone else with a Z3815A having problems?
--marki
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Today is start of new epoch.
As per:
http://adn.agi.com/GNSSWeb/
1753:0 Full GPS week since 1st epoch : day of week number
729:0 GPS Week since latest epoch : seconds of week at midnight for that day
So that explains what happened.
-Original Message-
From: time-nuts-boun...@febo.com
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