Hi Jimmy,
Someone touched on the idea of using a scope. Go to the Agilent site and
download a copy of the 10811 manual, 10811-90002.pdf. Section 3 describes how
to adjust the 10811 and gives info on how to time the phase drift to calculate
the frequency error. You can pull the time base out
I've been experimenting with digital thermal compensation on my GPSDO. The
results have been favorable for a 14 bit dithered PWM-based DAC, but leaves a
bit to be desired in the big picture. And it takes up a lot of program bytes
on my PIC.. What's the general consensus on this? Should
From: Attila Kinali att...@kinali.ch
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Sent: Wednesday, February 26, 2014 10:23 AM
Subject: Re: [time-nuts] Thermal Compensation: Digital vs Analog
On Wed, 26 Feb 2014 08
Hi Mark,
I'm neither an engineer, nor an expert, but here are my comments.
I think that the idea of 100ns/T is wrong. There are several variables that
control accuracy, but the time between pulses from your OCXO (assuming no phase
or frequency drift) isn't one of them. So, that gives 1/T.
Tom,
I took his 100ns figure to be simply the period of 10MHz. He mentioned using
an interrupt driven system, so the counts should not necessarily be limited to
100ns accuracy. At least on the PIC I'm using, the CCP and timer interrupts
don't seem to be synchronous with the PIC clock. I
this as an interrupt function, but after
looking at the manual, it's a matter of switchable dedicated hardware. Sorry
for the bad info.
Bob
From: Hal Murray hmur...@megapathdsl.net
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time
on your 1PPS pulse.
Bob
From: Alexander Pummer alex...@ieee.org
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Sent: Thursday, February 27, 2014 7:42 AM
Subject: Re: [time-nuts] GPSDO with all-digital phase
Hi Charles,
The problem is that the only information available is the fact that a phase
crossing occurred and whether there were more than 10M counts (or less) since
the last PPS. The phase error value is not available to me, nor is the
sawtooth value; which would of course be of no value.
Tom,
That's a pretty interesting idea. It makes me wonder if it would be worth it
to switch perhaps a 1/2W heat source (random number) off and on over the XO in
the UT+ say every minute or so.
Bob
From: Tom Van Baak t...@leapsecond.com
To: Discussion of
I suggested yesterday to periodically heat and cool the oscillator, but my post
may have been lost in the noise.
Bob
From: Didier Juges shali...@gmail.com
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Tuesday, March 4,
Hi Tom,
You may have missed TVB's post yesterday, quoted below. A hanging bridge is
an area on a timing receiver's plotted sawtooth correction value that stays on
one side of phase zero for some period of time. As a result of this bias, a
GPSDO that is not corrected for sawtooth will
I put my TIC to hardware, and have started testing it. Here is a sample run
comparing it against the 5334B with an off frequency OCXO. I've scaled and
rotated to tried to cancel out the length of the cables to the 5334B. Still
early days with it, yet.
at the precision of this thing.
It's like taking the 5334B and adjusting the focus knob. Of course it's not as
accurate, due to the way it works, but it will fit my needs well in my GPSDO.
Bob - AE6RV
From: Anders Wallin anders.e.e.wal...@gmail.com
To: Bob Stewart b
The link seems garbled for some reason with it inline so let me try again.
http://www.evoria.net/AE6RV/TIC/TIC2.bmp
From: Bob Stewart b...@evoria.net
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Sunday, March 9, 2014 10
Fellow Timenuts:
I'm trying to square reality with the modeling that I did, and nothing makes
sense. When I modeled the result of just my 2.4K resistor with the caps and
resistor the PIC datasheet says it has in it, there's no relationship. The
model says
I'll get millivolts out. Here's
is listed as 120pf. Here is a screenshot
of the relevant page.
http://www.evoria.net/AE6RV/TIC/ADC.png
Bob
From: Chris Albertson albertson.ch...@gmail.com
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts
to be argumentative, I'm just
trying hard to understand.
http://www.evoria.net/AE6RV/TIC/ChargeRamp.png
Bob
From: Bruce Griffiths bruce.griffi...@xtra.co.nz
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
is a good problem to have
and not a bad one. I'm sending a board to a friend soon, and if the results
repeat for him, it's not just a fluke.
Bob
From: Bruce Griffiths bruce.griffi...@xtra.co.nz
To: Bob Stewart b...@evoria.net; Discussion of precise time
Now that I've got the TIC going, I'm working on the PLL math for my GPSDO. My
question is about moving averages. I've put in a moving average for the TIC.
From that, I've calculated the slope, and have put a moving average on the
slope to settle it down. I think this boils down to a moving
Sent: Wednesday, March 12, 2014 12:51 PM
Subject: Re: [time-nuts] PLL Math Question
Bob,
On 12/03/14 18:24, Bob Stewart wrote:
Now that I've got the TIC going, I'm working on the PLL math
for my GPSDO. My question is about moving averages. I've
put in a moving average for the TIC. From
Hi Hal,
In the moving averages I'm doing, I'm saving the last bit to be shifted out and
if it's a 1 (i.e. 0.5) I increase the result by 1.
Bob
From: Hal Murray hmur...@megapathdsl.net
To: Discussion of precise time and frequency measurement
x_avg = x_avg + (x - x_avg) * a_avg;
Hi again Magnus,
In fact, I just post-processed some data using that formula in perl. It looks
great, and will indeed save me code and memory space. And, it can be a user
variable, rather than hard-coded. Thanks for the heads up!
Bob
. averaging way too long If not, maybe there will be
a good gain value that will be convenient to code the exponential average.
Thanks for the help,
Bob
From: Hal Murray hmur...@megapathdsl.net
To: Bob Stewart b...@evoria.net; Discussion of precise time
Hi Daniel,
re: FIR vs IIR
I'm not a DSP professional, though I do have an old Smiths, and I've read some
of it. So, could you give me some idea what the FIR vs IIR question means on a
practical level for this application? I can see that the MA is effective and
easy to code, but takes up
Hi Jim,
Thanks for your thoughts. Perhaps there are a few things that I know about my
particular system that have been discounted. I have mentioned them in passing,
but haven't collected them coherently for this thread. It's an 8-bit PIC, thus
floating point calculations have to be
Dennis,
I just realized that I could do the math in sixteenths. So, for 7/16ths
multiply by 7 before shifting(i.e. dividing) and rounding. That would probably
give enough granularity. I'll have to think about it. It does open new doors.
thanks,
Bob
.
This has been most informative and certainly gives me more options.
Bob
From: Chris Albertson albertson.ch...@gmail.com
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Sent: Thursday, March 13, 2014 5:42
I've gotten my PLL mostly working, but, since I'm using a nav receiver, it
looks like I may want to see if I can do a poor-man's sawtooth correction based
on GPS position changes. Has anyone done this or have a reference for a
project that has? It would seem to me that only the East-West
Hi Ignacio,
Thanks for the response. I've got a UT+ in the parts box. But that's not the
problem I'm trying to solve. I'm trying to make the best GPSDO that I can make
using a nav receiver at the moment. Call it an obsession if you like. It's OK
if I don't have corrections to the
://www.evoria.net/AE6RV/Nav/NavWander.png
Bob
From: Chris Albertson albertson.ch...@gmail.com
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Sent: Sunday, March 23, 2014 9:24 PM
Subject: Re: [time-nuts
I hadn't given any thought to correcting the linearity of the TIC I built, but
my PLL plots tell me I should do it now. Explanation: when I arrange things so
that the phase point is near the top of my TIC's range, it requires a smaller
movement than when the phase point is in the middle:
Thanks Charles. That makes sense, but at the expense of adding unwanted
complexity. As I've been moving the setpoint around this morning, I think I
see a way to characterize what it's doing. Maybe I can come up with a small
correction table or formula that's good enough for my purposes.
Bob
. I don't have any
sort of phase wrapping code, though, so I have to be careful how close to a
phase point I get.
Bob
From: Chris Albertson albertson.ch...@gmail.com
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time
albertson.ch...@gmail.com
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Sent: Wednesday, March 26, 2014 11:25 AM
Subject: Re: [time-nuts] RC TIC linearity correction?
Yes a lookup table would be easy. But how to create the table
What about the other side of audio-phoolery: audio FFT? I'm thinking more
along the lines of an ARRL FMT.
From: Tom Van Baak t...@leapsecond.com
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Thursday, March 27, 2014 6:10
To further Brian's comment: you have to keep in mind that the interrupt routine
interrupts the mainline code, and not the other way around. So, you set a
semaphore in your mainline code and your interrupt routine checks to see if
that's set when it starts, or at least before it uses any
Have you considered reading the timer only at PPS? You don't need to keep
track of the actual count. You just need to keep track of the difference
between counts at each PPS. Resolution isn't a problem since the difference in
the lower 16 bits is a fixed number for your purpose. IOW,
My Adafruit has gone walkabout again. This is a different unit than the one I
spoke about some months ago. It's been about 150 ft from my actual location,
which has, of course, made a mess of my GPSDO. Well, at least it verified my
unlock code. I did a POR and it seemed to come home, but
stability as well.
On Apr 10, 2014 5:51 PM, Bob Stewart b...@evoria.net wrote:
My Adafruit has gone walkabout again. This is a different unit than the one I
spoke about some months ago. It's been about 150 ft from my actual location,
which has, of course, made a mess of my GPSDO. Well
FWIW, I set the DAC to midpoint and use a binary search to get to frequency.
On my system, I start off with a change of 0x80 and work my way down to 0x04 in
powers of 2 (0x80, 0x40, 0x20, etc). Once I get to 256 seconds between DAC
changes, I light the PLL fuse. I could probably get away
, then it drifts off, your PLL stops, and you wait till
you drift back to the phase point. Rinse, repeat, fail. But, it's always
possible that you can see something in the data that I didn't.
Bob
From: Chris Albertson albertson.ch...@gmail.com
To: Bob Stewart b
on one side and it's now
gone to center, a bridge on the other side, or back to a sawtooth that averages
to zero. That's probably still pretty poorly said, but it's way past my
bedtime.
Bob
From: Bob Stewart b...@evoria.net
To: Discussion of precise time
(MT3339) problems today
On 10/04/14 23:48, Bob Stewart wrote:
My Adafruit has gone walkabout again. This is a different unit than the one
I spoke about some months ago. It's been about 150 ft from my actual
location, which has, of course, made a mess of my GPSDO. Well, at least it
verified my
I've done as much as I can do with my little Adafruit, so I guess it's time to
move to a timing receiver. I already have a UT+, so I might as well make use
of it. My thought was to use the NTP refclock driver and probably take the
sawtooth from SHMEM with a simple C program to pass to my
the
secret handshake. Writing the software to extract the sawtooth is no
big deal. It has version 2.2 of the firmware.
Bob
From: Bob Camp li...@rtty.us
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
have the right document.
Bob
From: Bob Camp li...@rtty.us
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Sent: Saturday, April 19, 2014 7:03 PM
Subject: Re: [time-nuts] NTP and Oncore UT+
Hi
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Saturday, April 19, 2014 9:36 PM
Subject: Re: [time-nuts] NTP and Oncore UT+
On Sat, Apr 19, 2014 at 9:18 PM, Bob Stewart b...@evoria.net wrote:
Somehow I missed that page in all the times I looked through the Oncore
of holdover. Lastly, you get to choose between it
being an ideal time standard vs. an ideal frequency standard.
/tvb
p.s. Please fix your address book. The correct email for the list is
time-nuts@febo.com
- Original Message -
From: Bob Stewart
To: time-nuts-ow...@febo.com
Sent: Tuesday
I mentioned to Tom that I had seen the xgps program duplicate a lot of its
satellites when I missed a PPS. I noticed my GPSDO go into holdover so I
quickly brought up xgsp and noticed it happening again. This screen showed a
few times intermixed with a normal screen. I have no idea whether
Given the state of the GPS chip, would it really take that big an investment to
just add in the firmware to do timing? Or have the manufacturers just made a
marketing decision to keep that a high end market as long as they can?
Bob
From: Bob Camp
I was wondering if anyone has a decent interface to the Adafruit and related
receivers for Linux? By that, i mean something like the Windows tools that
Globaltop provides, or even just the ability to separate out the responses to
the PMTK commands from the NMEA traffic.
Bob - AE6RV
Tom,
Any progress on the Adafruit PPS study?
(Hope this isn't a dupe. Yahoo's mail scripts have problems today.)
Bob
From: Tom Van Baak t...@leapsecond.com
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Monday, April 28,
Can anyone suggest a PIC programmer that will work with Piklab on Linux? The
replacement serial board I just bought won't drive my JDM Classic PIC
programmer. It doesn't reliably drive my LIRC IR transmitter either, so I have
to devote the serial port on my motherboard to LIRC. My GPSDO
I neglected to mention that I'm pretty much limited to USB or ethernet (if such
a programmer exists) at this point.
Bob
From: Bob Stewart b...@evoria.net
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Wednesday, May 14
Hi Rudolf,
The Pickit2 configuration choices were a bit confusing, so I decided to order a
different serial board that contains actual 16550s. Now that I've had a chance
to assimilate what I've learned, the problem is traced to the 3 Volt 3243 chips
that are in today's serial boards. After
Hal, you bring up an interesting point: Is the receiver in a Z3801 inherently
more accurate in position reporting than the receiver in an Adafruit? Somehow
I doubt it, if for no other reason than the improvements in technology.
(Excluding any programming errors that may or may not exist in
Now that my TIC is working with Bert's board, I'm considering taking the next
step of designing a GPSDO from scratch. There are several projects I'd like to
do with a dsPIC33, so that was a natural choice. But I now understand that it
has an audio DAC and is not recommended for process
they call the DAC default register a
safety feature for industrial control applications, and then a few inches later
a black box warns that it's not recommended for control type applications.
Bob
From: Poul-Henning Kamp p...@phk.freebsd.dk
To: Bob Stewart b
some of the same issues. Even some pretty fancy
outboard ADC’s only work well at DC if you put a chopper around them.
Bob
On Jun 2, 2014, at 7:22 PM, Bob Stewart b...@evoria.net wrote:
Hi Poul,
I've been reviewing microchips literature and the way I read it is that the
DAC isn't sensitive
There was a recent discussion with the above subject line about SVN-64. I've
noticed that my Adafruit hasn't given me any holdovers for a few days, so I
checked on the sat's status. The link below says it's been usable since May30.
Hmmm.
http://www.navcen.uscg.gov/?Do=gpsShowNanunum=2014047
Once I got my TIC going, I suppose it was inevitable that I build a GPSDO with
a dsPIC33. I have a few dsPIC specific questions for anyone who designs with
them.
1. VCAP. The datasheet says that it should be a surface mount device. I had
hoped to avoid those. Can I get away with a 10uf
In an offline communication, I suddenly realized that I hadn't given any
thought to the user interface for my GPSDO. Is there an accepted standard
interface for GPSDOs, or is that a murky Microsoft-esque world of patents and
lawyers?
Bob - AE6RV
.
Bob
From: bownes bow...@gmail.com
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Sent: Wednesday, June 25, 2014 7:35 PM
Subject: Re: [time-nuts] GPSDO standard interface?
Well, I built one
-
From: Bob Stewart b...@evoria.net
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Wednesday, June 25, 2014 5:10 PM
Subject: [time-nuts] GPSDO standard interface?
In an offline communication, I suddenly realized that I hadn't given any
thought to the user interface
Hi Mark,
Thanks for the response. I'll take a look at heathgps.cpp. I had hoped not to
have to actually look through code to divine an interface, but if that's the
way it is, then OK. I am planning on the output of at least position,
corrected phase error, DAC value, ambient temperature,
Perhaps the misunderstanding happened when I mentioned two UARTs and two tty
interfaces. Using a standard tty interface has nothing to do with how it gets
to the monitor hardware once it leaves the board. It's the same physical
interface that's used by the receiver boards; whether Adafruit,
You might be thinking of the file that David Byrne sent to the HP list last
year on 9/7/13. It was an article by C. L. Stong and I think it was published
in The Amateur Scientist in 1963. You should be able to find it in the HP list
archives.
Bob
From:
There's an interesting (and on topic) project in that book starting on page
335, discussing a home-made Magnetic Resonance Spectrometer. I wonder if any
time-nuts have constructed such a device, and what potential accuracy it would
have?
Bob - AE6RV
From:
Jim,
Are you trying to find out how to hook up a receiver in your office/radio room
to an antenna that is some ways away? Or are you specifically trying to
remotely hook up a receiver near your antenna? If the former, just use RG-6,
like for cable TV, with adapters on each end. RG-6 has
the systems gpio and serial ports attached?
Thanks to you both for answering.
jim
On 7/1/2014 9:30 PM, Bob Stewart wrote:
Jim,
Are you trying to find out how to hook up a receiver in your
office/radio room to an antenna that is some ways away? Or are you
specifically trying to remotely
First, an apology. When I changed the topic on my original post, I thought
that would be OK. Apparently that's still a thread-jacking. Sorry.
I'm still interested in this Magnetic Resonance Spectrometer thing, though. On
page 335 of the pdf linked below by Dave, there's an experiment with
Thanks Brooke. I'll look into it. It would be interesting to try to develop a
frequency standard from a test tube of water.
Bob
From: Brooke Clarke bro...@pacific.net
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement
I'm a bit confused about what you're asking. You discuss antennas but you show
pictures of a GPS receiver. They're not the same thing. I use a puck antenna.
They cost about $6 on ebay, and take their power from the coax. Normally your
GPS receiver supplies power to the coax, so you don't
Have you looked into NTP for Windows?
Bob
From: Max Robinson m...@maxsmusicplace.com
To: Time Nuts time-nuts@febo.com
Sent: Saturday, July 12, 2014 6:29 PM
Subject: [time-nuts] Setting Windows XP clock.
As some of you no doubt know microshaft has stopped
I got one of these recently, along with the adapter board. This is the ublox
only version, and I am using u-center version 8.11 software. I am unable to
make it work properly. The NMEA section happily sends out messages, but I
cannot get anything else to work. e.g. it ignores the commands
experienced
problems.
Bob
From: Art Sepin a...@synergy-gps.com
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Sent: Tuesday, July 15, 2014 5:58 PM
Subject: RE: [time-nuts] Synergy-GPS SSR-6tru problems
Bob
us exactly what you are
plugging it into and through what signal path you are issuing the commands.
On 7/15/2014 2:36 PM, Bob Stewart wrote:
I got one of these recently, along with the adapter board. This is the ublox
only version, and I am using u-center version 8.11 software. I am unable
From: Dennis Ferguson dennis.c.fergu...@gmail.com
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Cc: Bob Stewart b...@evoria.net
Sent: Tuesday, July 15, 2014 11:46 PM
Subject: Re: [time-nuts] Synergy-GPS SSR-6tru problems
On 15 Jul, 2014, at 16:32 , Bob Stewart b
at 2:54 PM, Bob Stewart b...@evoria.net wrote:
I fooled around with PUBX 41, and can't get the board to respond.
I had some problems but that's because they sent the wrong
configuration (a 16062133G). What's the part number? Assuming it
hasn't changed a TRu is 16062152G.
I don't have the ability
As a reminder, I received an SSR-6tru receiver from Synergy, along with their
M12 adapter, which allows you to plug it into a slot for an Oncore GT+, UT+, or
VP. I was unable to get the receiver to respond to any commands from the
u-blox u-center software.
After a lot of troubleshooting, I
today.
/tvb
- Original Message -
From: Bob Stewart b...@evoria.net
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Sent: Wednesday, July 23, 2014 3:19 PM
Subject: Re: [time-nuts] Synergy-GPS SSR-6tru Problem Resolved
As a reminder
was talking about. A
real class act all around!
Bob - AE6RV
From: Art Sepin a...@synergy-gps.com
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Cc: Tom Van Baak t...@leapsecond.com; Dusty Morris doxielove
I've run into a noise problem on the EFC line of my GPSDO engine at the
frequency of the oscillator. I've traced the source down to the 74HCT365 I'm
using to output the 1(or 5)MHz and 10MHz signals. When I pull it, the EFC
quietens down a lot. I'm seeing about 50mv of 10MHz noise at the
with an
X10 probe.
Bob
From: Bob Stewart b...@evoria.net
To: Time Nuts time-nuts@febo.com
Sent: Tuesday, August 5, 2014 1:36 PM
Subject: [time-nuts] Effects of noise on EFC line?
I've run into a noise problem on the EFC line of my GPSDO engine
What about a PC sound card?
From: Alexander Pummer alex...@ieee.org
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Thursday, August 7, 2014 5:06 PM
Subject: Re: [time-nuts] Low noise powersupplies
to measure a power supply
Hi Bob,
I hadn't even considered a filter in the OCXO. This isn't a 10811, but that's
the OCXO I have a schematic of, so I'll assume that's the benchmark. Following
the EFC in, it looks like it goes to a 100K resistor and then tees to the 100pf
varicap and a 15pf to the xtal. Other caps are
I've been using one for over a year. They take 12V to power, and they have a
VRef output around +6.25V, which implies an EFC range of 0-6V. Unless you get
one that's aged out, an EFC range of 0-5V should be fine. The VRef has a bit
of 10MHz on it on mine. All in all, it seems to be a good
I've had the LEA-6T sitting in survey-in mode for about 17 hours, and at this
point, the u-center software says that the Mean 3D Std Dev is 0.109 meters.
Given that my antenna is just a puck at the peak of the attic (never got around
to adding the DIY choke-ring), has this reached the silly
Hi Dan,
I think you're looking for the u-center software. Finding software on that
site can be difficult, so it's easier to resort to a websearch. There's a link
to the latest software on this page.
http://www.u-blox.com/en/evaluation-tools-a-software/u-center/u-center.html
As to the
On Aug 23, 2014, at 7:38 PM, Bob Stewart b...@evoria.net wrote:
I've had the LEA-6T sitting in survey-in mode for about 17 hours, and at this
point, the u-center software says that the Mean 3D Std Dev is 0.109 meters.
Given that my antenna is just a puck at the peak of the attic (never got
I have my GPSDO developed well enough now that I'm correcting for the
quantization error given by my LEA-6T. As I watch the phase difference plot,
it seems a bit more noisy than it should be. I've also had to make the DAC
pretty active to keep the phase noise on a short leash. So, I'm
And finally is an ADEV of approximately the same timeframe of the Rb
against the OCXO output as measured by my 5335A. Here the Rb phase is
unwrapped.
http://evoria.net/AE6RV/TIC/Rb.png
Bob
From: Poul-Henning Kamp p...@phk.freebsd.dk
To: Bob Stewart b
on the DAC plot. I did change the differential algorithm since I tried it with
low gain, so maybe it'll help.
Bob
From: Poul-Henning Kamp p...@phk.freebsd.dk
To: Bob Stewart b...@evoria.net
Sent: Wednesday, August 27, 2014 2:02 PM
Subject: Re: [time-nuts] OCXO Phase
.)
From: Poul-Henning Kamp p...@phk.freebsd.dk
To: Bob Stewart b...@evoria.net
Sent: Wednesday, August 27, 2014 2:02 PM
Subject: Re: [time-nuts] OCXO Phase Noise Measurement in Primitive Conditions
In message 1409165381.1098.yahoomail...@web142702.mail.bf1.yahoo.com, Bob Ste
wart
. I feel like I'm finally
getting somewhere with this random noise from the OCXO.
Bob
From: Poul-Henning Kamp p...@phk.freebsd.dk
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Sent: Thursday, August
Hi Attila,
Is wood, nails, and asphalt shingle really that big of a problem at these
frequencies? The antenna is within 2 ft of the highest point of the roof.
Bob
From: Attila Kinali att...@kinali.ch
To: Bob Stewart b...@evoria.net; Discussion of precise
: Poul-Henning Kamp p...@phk.freebsd.dk
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Sent: Thursday, August 28, 2014 1:04 AM
Subject: Re: [time-nuts] OCXO Phase Noise Measurement in Primitive Conditions
In message
as I loosen the gain values.
Bob
From: Bob Camp kb...@n1k.org
To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency
measurement time-nuts@febo.com
Sent: Tuesday, September 2, 2014 6:38 AM
Subject: Re: [time-nuts] OCXO Phase Noise
Hi Adrian,
Actually no. This ADEV is a plot of the sawtooth-corrected 1PPS signal from
the GPS receiver (LEA-6T) measured by the TIC in my GPSDO against the
output of its OCXO.
Bob
From: Adrian rfn...@arcor.de
To: Bob Stewart b...@evoria.net; Discussion
Hi Magnus,
I knew I was missing something! I'll warm up the Rb and test against that
again.
Thanks!
Bob
From: Magnus Danielson mag...@rubidium.dyndns.org
To: time-nuts@febo.com
Sent: Tuesday, September 2, 2014 3:27 PM
Subject: Re: [time-nuts] OCXO Phase
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