On 2/21/14 5:37 PM, Scott McGrath wrote:
It may be a downconverter rather than a filter some GPS time systems notably
ones by true time used an active down converter to transform signal to baseband
for long cable runs. Voltage to converter was rather high as I recall
Sent from my iPhone
I ran across these units
http://www.conwin.com/time-frequency_references-gps_disciplined-gps_references.html
and I found some references from a few years ago in the time-nuts
archives, but I can't find any data on phase noise, etc. for the
disciplined output.
The data sheet/user manual/etc
On 2/22/14 5:17 AM, Jimmy Burrell wrote:
I need some help with a 'noob' question regarding some practical
examples in some of the NIST literature. When attempting to compare
two clocks, I'm a bit confused on the subject of exactly how to use
my counter to compare a delayed clock relative to
on my
sample unit were significantly worse than what they show in their plots no
matter what I tried, and quite large phase/frequency jumps when
disconnecting/re-aquiring GPS.
Drawbacks of NCOs versus GPSDOs I guess.
Bye,
Said
Sent From iPhone
On Feb 22, 2014, at 5:33, Jim Lux jim
On 2/22/14 6:06 PM, saidj...@aol.com wrote:
Jim,
not sure if I had sent these before, or if you found them in the archives,
here are my ADEV, phase noise, and frequency stability measurements results
of the FTS-250.
All I did was remove the GPS antenna for about 10 seconds during the test
to
On 2/23/14 8:11 PM, Daniel Mendes wrote:
This is a different breed of time nuttery than usual in this list but i
think that at least some of you will enjoy it:
http://www.behance.net/gallery/FLUX-1440/2420150
Found it at hack a day
An enormous amount of work went into painting the
On 2/24/14 6:08 AM, Chuck Harris wrote:
Really impressive would be to have it create the
patterns that make the numeric display out of only
several feet of slowly moving rope connected as a
loop... but that would require some thinking, rather
than just a brute force approach.
It's art, after
On 2/24/14 8:17 AM, Poul-Henning Kamp wrote:
In message caa-f0u_jbz5dyb+hacmwfpkz6vhfo7arz+jpsmhrt9uss2n...@mail.gmail.com
, Pete Lancashire writes:
http://www.hp.com/hpinfo/abouthp/histnfacts/publications/measure/pdf/1968_09.pdf
pages 8 9
As far as I know, those satellites never made it
On 2/25/14 1:40 PM, Tom Van Baak wrote:
So what's all this about a Thallium Beam Tube???
For info about the pro/con of Thallium beam frequency standards, see:
http://tf.boulder.nist.gov/general/pdf/9.pdf
http://tf.boulder.nist.gov/general/pdf/211.pdf
On 2/26/14 12:44 AM, Hal Murray wrote:
rich...@karlquist.com said:
Solid dielectric cable and connectors of 3.5 mm size are mode limited to 18
GHz. That is why there is so much stuff rated at 18 GHz as opposed to 16 or
20 GHz.
Thanks. That's what I was looking for.
Wiki says that SMA
On 2/27/14 6:40 AM, Didier Juges wrote:
The BBB has 2GB of flash on board (non removable) and has a micro SD socket.
Would not be too hard to keep a backup copy of the OS and apps on the SD card
so that it would be easy to boot from SD and reload the built-in flash if the
BBB fails to boot
On 3/2/14 8:32 AM, Glen Hoag wrote:
FSCM 38243 is the manufacturer information. FSCM is the Federal Supply
Code for Manufacturers, which appears to be a subset of CAGE (Commercial
and Government Entity) codes maintained by the Defense Logistics
Agency. FSCM 38243 appears to be PG Electronics
On 3/2/14 11:09 AM, Chris Albertson wrote:
Junk crystals are good thermometers. Ballpark is 1 ppm/degree-C
So does this mean I can epoxy a sandstone power resister to a junk
crystal and keep the frequency exactly perfect by varying the power in
the resister?
Yes.. but you have to hold
On 3/2/14 12:21 PM, Bob Camp wrote:
Hi
As long as your resistor keeps the temperature to within a micro degree it will
do pretty well.
Oh, you were looking for 1E-12.. I was thinking 1E-9 would be good enough.
The other issue is that the phase noise might be pretty bad with a cheap
On 3/2/14 1:00 PM, Magnus Danielson wrote:
On 02/03/14 21:45, Bob Camp wrote:
Hi
The gotcha is that there are second order temperature effects. If you
are going to run the crystal very far off turn, you need to keep it
more stable than you might think.
hysteresis, memory effect, restart of
As Jim mentions in another post, you can run on the fundamental and the third
(or 5th or 7th) and get a thermometer out of the delta between the two modes.
The gotcha is that a change in load impedance will shift the frequencies
unequally. That will give you an apparent temperature change.
I
On 3/3/14 2:18 AM, Hal Murray wrote:
Junk crystals are good thermometers. Ballpark is 1 ppm/degree-C
albertson.ch...@gmail.com said:
So does this mean I can epoxy a sandstone power resister to a junk crystal
and keep the frequency exactly perfect by varying the power in the resister?
On 3/7/14 12:31 PM, Chris Albertson wrote:
On Fri, Mar 7, 2014 at 10:28 AM, Lars Walenius
lars.walen...@hotmail.com wrote:
Chris, about using one Arduino for two GPSDO controllers:
Even if a microcontroller has lots of capacity I would recommend to use
separate controllers for each
On 3/7/14 3:33 PM, Chris Albertson wrote:
Let's see what is needed.
The ADC is 10-bits so it can read to one part in 1024. It's a 5 volt
full scale so we are only able to measure 5 millivolt increments
if you use the teensy3 it has a 16 bit ADC with realistically, about 13
bits
On 3/12/14 10:06 PM, Chris Albertson wrote:
On Wed, Mar 12, 2014 at 9:13 PM, Daniel Mendes dmend...@gmail.com wrote:
This is a FIR x IIR question...
moving average = FIR filter with all N coeficients equalling 1/N
exponential average = using a simple rule to make an IIR filter
Isn't his
On 3/16/14 8:13 AM, d0ct0r wrote:
Thanks ! Looks like I am on the right track.
I've attached couple of documents which could be useful. I'am going to
use two separated voltage regulators for VCC/AVDD and DVDD. And use 10
Ohm / 100Mhz ferrite board and few capacitors to separate VCC and AVDD.
On 3/16/14 9:34 AM, d0ct0r wrote:
I would assume that using two voltage regulators will spread the load.
For the AD9851 I'am planning to put external radiator glued on top of it.
It's not the power dissipation of the regulators that's the concern,
it's the dissipation of the 9854. A
On 3/18/14 10:18 PM, Tom Van Baak wrote:
If you can design a system that can handle 6.5 billion requests per day, this
opportunity is for you...
https://www.fbo.gov/spg/DOC/NIST/AcAsD/RFI_InternetTimeServiceComments/listing.html
Solicitation Number: RFI_InternetTimeServiceComments
For
Original Message
Subject: Re: [time-nuts] NIST time services
Date: Wed, 19 Mar 2014 10:21:17 -0700
From: Jim Lux jim...@earthlink.net
To: time-nuts@febo.com
On 3/19/14 9:50 AM, Chris Albertson wrote:
So they want to in-invent NTP?
I think NTP already services way more than
On 3/19/14 5:21 PM, Bill Hawkins wrote:
They only got one ping from INMARSAT at 64E above the Indian Ocean.
There was no other ping to triangulate the position.
One ping projects a circle on the Earth. The maximum flying range of the
plane determined the ends of the NE and SE arcs of that
On 3/20/14 12:07 AM, Poul-Henning Kamp wrote:
In message 279331507.5734621395275538874.JavaMail.actor@webmail5, iovane@inw
ind.it writes:
My question was on what would be the expected accuracy of the circle's radius.
Projected onto the surface of the earth, the uncertainty leaves a band
On 3/20/14 8:53 AM, Poul-Henning Kamp wrote:
In message 40280C39FE7D43C79313A1755BCAF58D@StanleyPC, Stanley writes:
Would think they have many other aircraft with known position stationary or
moving with location known to help improve the estimate.
They might have been able to do that while
On 3/21/14 8:52 PM, nuts wrote:
On Thu, 20 Mar 2014 14:42:42 -0400
Joe Leikhim jleik...@leikhim.com wrote:
I just red somewhere that the last ping was the only one recorded
by Inmarsat system, Pings up to that point were presumed to occur due
to known reporting intervals. So there is no track.
On 3/19/14 9:50 AM, Chris Albertson wrote:
So they want to in-invent NTP?
I think NTP already services way more than 6.5 billion per day. The
problem with NTP is while it is nearly optimal and provides the best
time accuracy for a given hardware/network setup it is not technically
traceable
On 3/23/14 10:48 AM, Paul wrote:
On Sun, Mar 23, 2014 at 1:08 PM, Bob Camp li...@rtty.us wrote:
I suspect that what NIST is looking for is somebody in the cloud business
(Amazon, Google, Microsoft, IBM) to step up and mention that they have
2,989,875 server racks scattered about the world and
On 3/24/14 6:15 PM, Chris Albertson wrote:
Yes, word is that they were able to determine the Doppler shift in the
plane's signal. I'm surprised this was even recorded but it must have been
in the satellite's telemetry downlink. Projecting radial velocity and
constraining it to be close to the
On 3/24/14 10:18 PM, David McGaw wrote:
I am surprised it took them this long. A number of satellite telemetry
systems can use doppler as a matter of course for locating transmitters,
such as Iridium and Argos.
Those are actually designed for measuring Doppler..
That's really the difference..
On 3/25/14 11:38 AM, J. Forster wrote:
Could well be. I never saw the bird, of course. The portable ground
station was roughly the same size as an OD Manpak radio of the period and
read out Lat/Long on LED digital readouts. In retrospect, it may have been
in the early 1980s.
Transit,
I've got some GPS-18x LVC units i'm using for a time reference, and
they're showing an odd behavior: the position isn't updating.
I moved them across the US (from Los Angeles to the east coast), and
when I powered them up here, it's returning the LA Lat/Lon (34N,118W),
the (reasonably
On 3/27/14 8:53 AM, David J Taylor wrote:
From: Jim Lux
[]
Has anyone seen a similar behavior? I've tried the power cycling, and
the Garmin reset command. I've not done the clear non-volatile
memory which makes it forget the almanac.
===
What
On 3/27/14 4:10 PM, Tom Van Baak wrote:
Recently I happened across an eBay listing for an Antelope Audio
Isochrome, a device that apparently packages an SRI-PRS10 rubidium
oscillator and distribution amplifier in a box and sells to
audiophiles for a price in the
True, the PRS10 is a better
On 4/3/14 8:17 PM, Chris Albertson wrote:
I just read about a discovery of a liquid water ocean on Saturn's moon
Enceladus. The method used was to measure the velocity of a
spacecraft as it makes a close fly-by. Gravitational anomalies will
cause the spacecraft to speed up or slow down as it
On 4/3/14 11:17 PM, Chuck Forsberg WA7KGX wrote:
One needs to know the carrier frequency. Must be a high quality reference
for the Cassini transmitter.
Two way measurements are most likely here (although Cassini does carry a
USO). So the downlink is locked to the uplink which comes from a
On 4/4/14 4:30 AM, Bob Camp wrote:
Hi
Back when they were designing this stuff, they were very interested in getting
into the parts in 10 to the 15th. They didn’t get there, but that was the
desire.
Roughly that...
http://lasp.colorado.edu/~horanyi/graduate_seminar/RSS.pdf is a good
On 4/4/14 7:39 AM, Bill Hawkins wrote:
Jim,
Thanks for sharing the details and preventing this subject from turning
into shared ignorance.
It was working on this kind of thing that led me to time-nuts in the
first place..
Deep Space nav is probably one of the most precise measurements made
On 4/4/14 5:01 AM, Dr. David Kirkby wrote:
On 4 Apr 2014 08:55, Tom Knox act...@hotmail.com wrote:
90 microns is approx a freq res of about 1 x 3.66 -12
Thomas Knox
Since the Doppler shift is prortional to the frequency, I can't see how
one can determine the absolute frequency.
But
On 4/4/14 9:34 AM, Chris Albertson wrote:
On Fri, Apr 4, 2014 at 6:19 AM, Jim Lux jim...@earthlink.net wrote:
Radio science and navigation measurements are quite impressive in their
accuracy and attention to detail. measuring range to cm (out of a billion
km, i.e 1 part in 1E14) and velocity
On 4/4/14 9:58 AM, Alex Pummer wrote:
gravitation measurement, particularly gravitation measurement in space
is based on the Eotvos -effect see here:
http://en.wikipedia.org/wiki/E%C3%B6tv%C3%B6s_effect and here:
http://en.wikipedia.org/wiki/Lor%C3%A1nd_E%C3%B6tv%C3%B6sand from
the begin
On 4/4/14 6:51 PM, Chris Albertson wrote:
The data connector is a standard 0.05 inch double row of male headers.
These are common but not nearly so common as the 0.1 type. I used a 2032
coin cell battery and holder I un-soldered from an dead PC motherboard.
Even a coin cell will last its shelf
On 4/4/14 5:45 PM, paul swed wrote:
I mean no disrespect to anyone here. Jacksonlabs makes some very fine
components. Brookes comment was spot on. What happens etc. I did run out to
the site and take a quick read. The short piece I read did not have a lot
of specifics or I simply missed them. It
On 4/10/14 2:38 PM, Hal Murray wrote:
Does anybody have a favorite low-cost ARM board? I'm looking for a simple
Arduino like setup rather than something that runs Linux. The idea is to get
32 bit counters so a bunch of the recent discussion can be ingnored.
teensy3.1.. ARM Cortex M0 in the
On 4/12/14, 12:50 PM, Bob Camp wrote:
Hi
I’ve been working with some friends on an ARM based Arduino project. The
support for ARM in the Arduino tool chain is still not really up to speed. It’s
actually been faster / easier to take the stuff we need over to another board
and tool chain than
On 4/14/14, 12:11 PM, ewkeh...@aol.com wrote:
Am experimenting with small low cost GPS antennas and am considering as an
alternative RTV/silicon. Any information on RF attenuation of RTV/silicon
at 1.6 GHz ?
Are you potting the antenna in a solid mass of silicone? Or using it to
seal an
On 4/15/14, 1:53 AM, nuts wrote:
I'd be inclined to look at radome construction.
http://www.mpdigest.com/issue/articles/2008/may/mfg/default.asp
The E-3 AWACS is mostly S-2 glass, but they need the strength. For a
radome sitting outside, you might be able to do better.
Radome design is
On 4/15/14, 8:13 AM, ewkeh...@aol.com wrote:
Working off list on a super high performance GPSDO but low cost thanks to a
time nut (sorry forgot his name) he directed me to DX.com which have ublox
with antenna for lwss than $ 23. Super performance and though they are out
of the one with 1 pps
On 4/15/14, 11:02 AM, ewkeh...@aol.com wrote:
The Gerber Baby Food Jar at Wall Mart $ 0.49
Is there a particular kind of food that works best? Perhaps strained
prunes has the best regularity?
___
time-nuts mailing list -- time-nuts@febo.com
To
On 4/15/14, 8:16 PM, nuts wrote:
I don't use the surf board resin. I use
http://www.tapplastics.com/product/fiberglass/polyester_resins/tap_marine_vinyl_ester_resin/34
I don't have specifics on what Tap sells, but vinyl ester resins have a
dielectic coeficient around 4 and dissipation of at
On 4/17/14, 11:09 AM, Lester Veenstra wrote:
The classic DIY test of material for RF use is give it 60 seconds in a
microwave oven.
If it gets warm, it’s not a good candidate.
that's fine if you're looking for a gross measure of suitability.
If you're concerned about things like dielectric
On 4/24/14, 6:26 PM, Said Jackson wrote:
Hi Magnus, Bob,
Thanks much for your kind words.
The failure rate is thankfully so low that we are not greatly alarmed, and
Microsemi has been a champ in resolving any failures with/for us when they did
show up. We are awaiting the results of the full
On 4/24/14, 11:14 PM, Attila Kinali wrote:
On Fri, 25 Apr 2014 08:33:06 +0300
MailLists li...@medesign.ro wrote:
The recently acquired cash cow isn't working exactly as
expected/advertised. We still don't have a clue when/if the fundamental
(as in physics laws) design (we can't officially
On 4/24/14, 11:43 PM, Magnus Danielson wrote:
Jim,
On 04/25/2014 05:32 AM, Jim Lux wrote:
On 4/24/14, 6:26 PM, Said Jackson wrote:
Hi Magnus, Bob,
Thanks much for your kind words.
The failure rate is thankfully so low that we are not greatly alarmed,
and Microsemi has been a champ
On 5/2/14, 7:07 PM, Tony wrote:
On 03/05/2014 02:07, Edesio Costa e Silva wrote:
Welcome!
Take a look at NavSpark from SkyTraq (http://www.skytraq.com.tw/).
They had
an Indiegogo
(https://www.indiegogo.com/projects/navspark-arduino-compatible-with-gps-gnss-receiver)
campaign recently and
On 5/4/14, 8:40 AM, Chris Albertson wrote:
Looks like this is all you'd need for most timing projects. Just add your
favorite OCXO and some wire.
The SPARC (not Spark) is actually a step up from ARM. It was developed by
Sun Microsystems (now Oracle) it is optimized for things like fast
On 5/4/14, 10:07 AM, Bob Camp wrote:
Hi
Well some of us still have RSX-11M (and RSTS/E) code floating around …..
B
As do I, but the stuff I'd actually reuse is pretty OS independent
(signal processing code in FORTRAN, and in reality, I'd most likely
rewrite it anyway.)
I suspect you'll
On 5/4/14, 11:38 AM, Chris Albertson wrote:
These guys claim IEEE-754 FPU. But this is not the board to use for a
Posix-like OS. For that you'd want disk controller, networking and so on.
Ah, so they did include the FPU: that's handy.
Actually, an in-ram file system, along with a decent
On 5/4/14, 11:44 AM, Bob Camp wrote:
Hi
Well I do have those Sparc machines sitting over in the shed ….. I
suspect hauling over the CRT monitor to go with it would be a bit of
a pain. I doubt I would win the “low power GPSDO of the year” award
with it.
Like it or not, once you get to 64
I'm in the middle of implementing a lightweight time distribution system
using SpaceWire (a fast point to point serial link with simple routers
to build networks).
SpaceWire provides a special token called a timecode which propagates
from a tick source to various nodes, but that just provides
On 5/26/14, 11:13 AM, Magnus Danielson wrote:
Hi Jim,
On 05/26/2014 07:43 PM, Jim Lux wrote:
I'm in the middle of implementing a lightweight time distribution system
using SpaceWire (a fast point to point serial link with simple routers
to build networks).
SpaceWire provides a special token
On 5/27/14, 10:24 AM, Brooke Clarke wrote:
Hi:
Classical tide gauges measure the height of the water relative to the
gauge. But since the gauge is attached to a tectonic plate it's
elevation is changing.
This is one of the problems I have with the claim that sea level is
rising at 2mm per
On 5/28/14, 6:04 AM, Tom Holmes wrote:
Which begs the question: just where the heck, exactly, is the center of the
Earth given that it is in the 'middle' of a molten and dynamic core. Are the
satellite orbits so stable and/or measurable around the center of
gravitational pull that the location
On 5/27/14, 9:21 PM, Chris Albertson wrote:
On 5/27/14, 10:24 AM, Brooke Clarke wrote:
BACK ON TOPIC... What does it take to measure ones distance from the
center of the Earth accurately enough to detect geological movement in
a reasonable amount of time? Measuring distance really is,
On 5/28/14, 2:11 PM, Tom Holmes wrote:
Thanks Jim.
So if, just for fun since this is time-nuts after all, I wanted to make a
similar measurement in my back yard here in the relatively stable Ohio,
would I be able rig something up to monitor the position changes? Obviously
a lot of averaging of
On 5/30/14, 2:41 AM, Dr. David Kirkby wrote:
On 28 May 2014 14:06, Tom Holmes thol...@woh.rr.com wrote:
Which begs the question: just where the heck, exactly, is the center of
the
Earth given that it is in the 'middle' of a molten and dynamic core.
I always thought that the centre was
On 5/30/14, 3:00 PM, Hal Murray wrote:
[Structure of Earth's core]
jim...@earthlink.net said:
Molten, but it's a composite material under a lot of pressure, so the
transition between liquid and solid isn't like between ice and water.
Think cold peanut butter.
Seismic evidence is how they
On 5/31/14, 5:48 PM, Bob Camp wrote:
Hi
A thousand chips at $1 a chip is a very different thing than a thousand chips
at $100 a chip. The next issue might be that they only have them in die form.
The issue after that probably is that you really want the version 3 (or 9)
chips that actually
On 6/2/14, 1:55 AM, Tom Van Baak wrote:
Has anyone else noticed this? Or know about this? Please respond only if you
have real information. I can speculate as well as anyone; so it's solid
technical, RF, EMF, or composite carbon fiber engineering info I'm looking for.
I haven't noticed it
On 6/2/14, 2:27 AM, Poul-Henning Kamp wrote:
It would be trivial to add a passive GPS repeater to the plane, but
the airtraffic industry has never been happy about people being
able to receive navigation signals inside planes, worrying that
somebody might try to blow up the plane at some
On 6/2/14, 7:16 AM, Brian Lloyd wrote:
On Mon, Jun 2, 2014 at 8:57 AM, Jim Lux jim...@earthlink.net wrote:
O, and since navigation using the ADF and tuning to a AM
broadcast station wasn't unusual.
Well, it is quite unusual for IFR (instrument flight rules) operation. But
VFR pilots would
On 6/3/14, 5:51 AM, Chuck Harris wrote:
nuts wrote:
Regarding radiation, I've used my Geiger counter at mile high altitudes
in Nevada and never got a count per second, even with the gamma shield
not used. You can look at the DOE CEMP stations:
1 Mile high is still on the ground compared
Does anyone have a feel for what the minimum size reflector at some
small distance would be detectable on a GPS timing receiver? WOuld you
be able to see a change of a 1 meter square reflector 10 meters away?
___
time-nuts mailing list --
Clarifying my previous question..
There's no doubt that multipath exists, and how to test is fairly
straightforward, whether with multiple antennas, cables, or waving
cookie sheets around..
What I was really asking is if anyone had observed this in the output of
their GPS receiver.
That
On 8/9/14, 9:33 AM, Magnus Danielson wrote:
Jim,
On 08/09/2014 05:31 PM, Jim Lux wrote:
Clarifying my previous question..
There's no doubt that multipath exists, and how to test is fairly
straightforward, whether with multiple antennas, cables, or waving
cookie sheets around..
Ultimately
On 8/9/14, 10:49 AM, Brooke Clarke wrote:
Hi:
I've been reading papers by Yingsi Liang who works for Xtendwave and she
seems to be the key person developing the new clocks.
I've starting collecting info on my web page:
http://www.prc68.com/I/Loop.shtml#PhaseMod
I don't understand how Xtendwave
On 8/9/14, 12:56 PM, Bob Camp wrote:
Hi
Keep in mind that the patent(s) do not keep you from building a part for your
own use.
AS I understand it, this is not technically true. You can practice the
patent to gain an understanding of it for the purposes of inventing
something new that is
On 8/9/14, 3:49 PM, Bob Camp wrote:
Hi
That’s not the way it was presented to me. My understanding is that the case
law on proving “individual study” versus “individual use” is a bit murky. I’m
certainly no lawyer (thank goodness ..).
murky is a good way to describe it...
On 8/9/14, 12:27 PM, John Seamons wrote:
On Aug 10, 2014, at 5:49 AM, Brooke Clarke bro...@pacific.net wrote:
I don't understand how Xtendwave can get patents when their work was partially
funded by NIST?
We had this discussion a few years back:
On 8/9/14, 9:36 PM, Lee Mushel wrote:
Jeeze, Brooke, I wish you hadn't brought up the possible patenting of
Time Delay Beam steering antennas! I wonder if my highly esteemed SDR
radio which I think uses some such technology, is illegal?
long since expired..
(but, I gotta say that a lot of
On 8/10/14, 5:41 AM, Bob Camp wrote:
Hi
Keep in mind that it’s relatively cheap (big company wise) to get a patent. It’s only got
major value once the courts uphold it as valid. That process costs real money. I’ve seen
a variety of estimates on how many patents get issued that would never
On 8/10/14, 8:30 AM, Bob Camp wrote:
Hi
…. which also eliminates a full examination and challenge.
Bottom line as I still see it -
For Time Nuts one off / home use / zero profit/ personal
experimentation, I would not worry about the patents that are or are
not present on the
On 8/10/14, 9:26 AM, Kenneth G. Gordon wrote:
On 10 Aug 2014 at 6:24, paul swed wrote:
Hello again, Paul. Thanks for replying. Please see below.
On iPhone
Yes but those stations are fsk so the offsets an issue.
As I understand it from back in the 1970s when I was first working on this
sort
On 8/10/14, 11:54 AM, Mike Feher wrote:
Unless on what you were working on it had a different meaning, MSK means
Minimal Shift Keying. It is still a PSK modulation of any order, however
the transition between significant phase locations is not instantaneous,
but, shaped in various ways to smooth
On 8/14/14, 11:12 AM, mike cook wrote:
WOW! Guaranteeing compliance with FINRA OATS 7430 !
Here it is..
All computer system clocks and mechanical time stamping devices must be synchronized
to within three seconds of the National Institute of Standards and Technology (NIST)
atomic
On 9/13/14, 7:33 AM, paul swed wrote:
Charles I literally just sat down to do some math. What you say is the same
thoughts I have. The information I have on NAA says that for 200bit msk its
a total of a 100 hz shift +/-50 Hz. That makes no sense I would think it
would be at least +/- 100 Hz.
On 9/13/14, 7:13 PM, paul swed wrote:
If NAA is transmitting 200 baud then I would expect the MSK carrier to be
+/- 100 Hz. Not +/-50 Hz.
I'd expect the total shift to be half the baud rate: 100 Hz..
___
time-nuts mailing list --
a far wide shift
then the baud. What you say would match what the tracor book says
and the system is designed for. I still do not see why if I offset
the LO to -150 hz I get a useful display to judge timing. I am
using the lissajous method. Regards Paul WB8TSL
On Sat, Sep 13, 2014 at 11:25 PM, Jim
On 9/23/14, 10:11 AM, Alexander Pummer wrote:
there is an interesting side effect with that phase modulation: in case
the crystal filter is narrow enough --to use for the old AM format--
the phase change creates an additional AM modulation, if you take in
consideration that effect by the
On 9/28/14, 10:09 PM, Peter Monta wrote:
How hard is the beam steering relative to everything else?
It's a weighted sum of the antenna signals (as with any phased array), so
the cost is the extra arithmetic to do this (on a per-satellite basis).
The weights can be computed open-loop from the
On 9/30/14, 12:44 AM, REEVES Paul wrote:
David,
Just a thought but have you tried Pasternack? They do 'custom' precision
cabling including 2.4mm connector options.
regards,
Paul, G8GJA
Rather than Pasternack, you might find the following sources useful
Citrus Cables does nice quality,
On 9/30/14, 4:56 PM, Dr. David Kirkby (Kirkby Microwave Ltd) wrote:
On 30 Sep 2014 14:16, Jim Lux jim...@earthlink.net wrote:
On 9/30/14, 12:44 AM, REEVES Paul wrote:
David,
Just a thought but have you tried Pasternack? They do 'custom' precision
cabling including 2.4mm connector options
At work, I'm putting together a multichannel stepped frequency CW radar
breadboard, and I'm looking for something to serve as a source that I
can step quickly.
I'm looking at stepping every millisecond or so. Right now, I use a
Ardunino type microcontroller driving a serial DAC driving a
On 10/7/14, 10:28 AM, Poul-Henning Kamp wrote:
In message 54341cbf.9080...@earthlink.net, Jim Lux writes:
Maybe some DDS in a box product? That will take my nice clean 10 MHz
reference?
DDS is by far the easiest, but the question is if it is clean
enough.
Yes, probably clean
On 10/7/14, 10:32 AM, Magnus Danielson wrote:
You should be able to use DDS test-boards and by timing your last write,
you should be able to time the frequency jump.
The STEL-1173 takes 6 bytes, but writing the last one latches all 6
bytes over to a single 48 bit word. I expect that other DDSes
On 10/7/14, 12:43 PM, Anders Wallin wrote:
We've been using/testing an AD9912 eval-kit board. It can take 10MHz input
and has an internal 66x PLL and VCO for a 660MHz DDS sample-clock (just out
of spec actually, vco is min 700MHz if I read the datasheet correctly).
Output looks like so:
On 10/7/14, 1:19 PM, Don Latham wrote:
I have two versions of the ADF4351 dds. One is the AD eval board, and the
other the TPI synthesizer
(http://www.rf-consultant.com/calibrated-signal-generator/) at $280 that might
do the job. The latter device performs well. It will be as good as the 4351, I
On 10/7/14, 4:43 PM, Bob Camp wrote:
Hi
The output spectrum of some DDS’s is pretty rich. You may find that a 1 GHz DDS
can be filtered to operate directly over the 3.1 to 3.4 GHz.
Oh, clever idea.. Yes.. there is substantial harmonic content, and one
could easily arrange to have more. And
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