On 7/6/13 2:46 PM, Mark C. Stephens wrote:
Hopefully HP Voltage Derated the Cap as well so it can handle our
250V here.. We are across the road from the main transformer for the
area so the voltage is highest at our place, I checked the meter box
this morning - it is 255-258V on all 3 phases,
On 7/6/13 5:26 PM, Mark C. Stephens wrote:
The elephant in the room thing with me is SAFETY :)
I mean, can this be a fire hazard, what about the insulation breakdown on the
secondary winding etc..
Most transformers have a voltage rating on ALL windings that is greater
than several times
On 7/6/13 7:23 PM, Bob Camp wrote:
Hi
Ok, lets *assume* there is some uber secret gizmo in the sat that makes the
unsupervised signal absolutely perfect when transmitted from the sat.
The sat still moves relative to the ground. It's speed is a vector in three
dimensions (up / down , north /
On 7/5/13 8:44 AM, Bob Stewart wrote:
Wouldn't a Cs or Rb clock in orbit be slow due to relativistic effects? I'm
pretty sure there is a relativistic correction to the GPS clocks.
Bob - AE6RV
I believe that the original WAAS repurposed transponders intended for
other L-band satellite
On 7/5/13 11:37 AM, Attila Kinali wrote:
On Fri, 5 Jul 2013 12:14:20 -0400
Bob Camp li...@rtty.us wrote:
Indeed the atomic clocks on sats are set up so they can tune far
enough to take out the relativistic effects. That (and a bunch of other
things) makes them somewhat more expensive than
An ION paper by Nagle, et al.
Nagle, J. R., Van Dierendonck, A. J., Hua, Q. D., INMARSAT-3 NAVIGATION
SIGNAL C/A CODE SELECTION AND INTERFERENCE ANALYSIS, NAVIGATION,
Journal of The Institute of Navigation, Vol. 39, No. 4, Winter
1992-1993, pp. 445-462.
Inmarsat-3, the next generation of
On 7/3/13 12:42 PM, Azelio Boriani wrote:
Sure about the bent pipe? If so it seems that much power is required
at the transmitting ground station...
Much equivalent power is required. If you have a 20 meter or so
antenna, it doesn't take much to get a pretty high EIRP.
On 7/3/13 2:21 PM, Dennis Ferguson wrote:
On 3 Jul, 2013, at 11:47 , Bob Camp li...@rtty.us wrote:
The pipe in this case is up on one frequency and down on another. The
conversion oscillator on satellite that's the weak link, no matter how good the
signal from the ground happens to be.
On 7/4/13 7:33 AM, Didier Juges wrote:
That works well for transponders with o LY one signal. On commercial
satellites, each transponder is shared among multiple signals, so that would
not work.
Ah, yes.. if it's a linear transponder/translator..
On 7/3/13 6:58 AM, Bob Camp wrote:
Hi
Since the LEA6-T will do conventional RINEX dumps, I suspect that all they are
doing is very long averaging on the data. I doubt the LEA6-T is the magic part
of the setup.
or sending the RINEX files to JPL for processing...If you don't need
real time
On 7/2/13 7:41 AM, J. Forster wrote:
A few years back, some Group Owners, especially of ham lists, outlawed the
mention of eBay, because the concept of selling something to the highest
bidder somehow offended 'the ham ethic' that stuff should go to the 'most
needy or deserving' as measured by
I had a chance to go through the Time and Navigation exhibit at the
National Air and Space Museum last week. From a time standpoint,
there's probably not much there that time-nuts don't know already, but
it's kind of cool to see cleaned up examples of equipment from days gone
by. (there's an
On 6/30/13 7:43 AM, Charles P. Steinmetz wrote:
A three-terminal regulator (3TR) comprises (i) a voltage reference, (ii)
an error amp, and (iii) a current amplifier. There is no need to
duplicate the voltage reference or the error amp just because you need
more current. In fact, they can only
On 6/30/13 8:48 AM, Brian Alsop wrote:
Maybe I read the original posting wrong but I think this thread has
departed greatly from the original posting.
What I thought the posting said:
1) The already present transformer can produce ~20 V DC unregulated at
sufficient current.
2) The desire was to
On 6/30/13 12:35 PM, Bob Stewart wrote:
I believe the original problem was that the raw unregulated voltage may
be marginally too high for a conventional three-terminal to take safely
Hi Ed,
Not really. The voltage is in line with the product specs for a 7812 (35V
max), as is the current I
On 6/24/13 6:48 PM, Tom Miller wrote:
I wonder what the actual distance is using current GPS survey processes?
Tom
SLightly different, because there are some faults running across there
and there have been some earthquakes with displacement.
On 6/23/13 10:48 PM, DaveH wrote:
Something a bit similar was first published by Nick Hood in 2007.
Here is a copy:
http://www.sciencebuddies.org/science-fair-projects/project_ideas/Phys_p056.
shtml
Here is Nick's website:
http://cullaloe.com/
Some people use marshmallows.
Dave
the only
On 6/24/13 10:08 AM, Chris Albertson wrote:
Using only moderately accurate equipment, like mechanical clocks and
meter sticks Albert Michelson has able to measure the speed of light and
determine it was a constant in all directions. It was this work the
prompted Albert Einstein to think about
On 6/24/13 5:21 AM, Brian Alsop wrote:
The time issue was effectively eliminated by the Michaelson-Morley
interferometer. One used a monochromatic light and an array of mirrors
which split the light in opposite directions around the track. The two
beams were recombined and an interference
On 6/24/13 2:26 PM, Chris Albertson wrote:
On Mon, Jun 24, 2013 at 1:55 PM, Jim Lux jim...@earthlink.net wrote:
On 6/24/13 10:08 AM, Chris Albertson wrote:
Isn't that the Fizeau technique, which antedates Michelson's?
Michelson got the precision good enough that it finally put
On 6/24/13 3:01 PM, Bob Camp wrote:
Hi
I'm not so sure that slow would work. With all the sat's moving various
directions all the time, I suspect you need to do a solution fairly quickly. If you don't
the stale data messes up the solution. Also you need the correlators to work fast enough
to
On 6/24/13 4:16 PM, jmfranke wrote:
The tuning fork was used with a clock. The clock was checked against
astronomical measurements.
http://www.schoolphysics.co.uk/age16-19/Wave%20properties/Wave%20properties/text/Speed_of%20light/index.html
On 6/23/13 10:47 AM, Chris Albertson wrote:
Magnetic cores were not invented until the 1950's and realy cam into use as
tubes were beibg replaced by SS. But there isnot reason yu can't build a
tube computer with core memory. I have actually seen and used a computer
that had one megabyte of
On 6/23/13 2:50 PM, Paul Berger wrote:
Hi:
The SAGE computers, which I had the pleasure of seeing the last two
operating, had an all vacuum tube array of core that consisted of 33
planes of 64 x64 cores for about 16K worth of memory.
I was wondering about the Q7.. it was all vacuum tube, but
I think that doing the PN code and correlator is something that could be
done with tubes (especially if you didn't want to go P-code).
I suppose you could use a counter to record the changes in code phase as
you scan for the correlation peak, so that gets you your numeric code phase.
Getting
On 6/22/13 3:28 PM, Magnus Danielson wrote:
On 06/23/2013 12:04 AM, Jim Lux wrote:
I think that doing the PN code and correlator is something that could be
done with tubes (especially if you didn't want to go P-code).
I suppose you could use a counter to record the changes in code phase as
you
On 6/22/13 4:38 PM, Magnus Danielson wrote:
electromechanical.. like omega receivers. rotary transformers can do
very high quality trig functions, but do you actually need trig
functions assuming you're just solving for X,Y,Z,T.
Oh yes. Check IS-GPS-200F, clause 20.3.3.4.3 User Algorithm for
On 6/22/13 5:35 PM, Bob Camp wrote:
Hi
How stable a 1.023 oscillator? How much pull range on that oscillator? H…..
Doppler is the big component..several kHz..
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On 6/20/13 4:57 PM, Gary wrote:
A common scheme in metal deposition measurement is to measure the frequency of
a crystal prior to starting the deposition process, then monitoring the
frequency shift of the crystal as the metal is sputtered.
I was told crystals are tuned this way at the
On 6/17/13 5:33 AM, Peter Gottlieb wrote:
The current distortion from simple transformer-rectifier-capacitor power
supplies contains a lot of third harmonic content. In a 3 phase system
(as are all distribution systems for commercial and industrial) the
third harmonic ADDS in the neutral, or
On 6/17/13 10:39 AM, Poul-Henning Kamp wrote:
In message 51bf15a8.40...@earthlink.net, Jim Lux writes:
The issue also arises with fluorescent [...]
As folks transitioned to the newer ballasts, the non-sinusoidal
current problem probably got worse.
I don't know about US, but in EU
On 6/14/13 10:55 AM, DaveH wrote:
Most RTG sources use Plutonium 238 or Strontium 90. Primary decay component
is Alpha particles which can be stopped dead by a few mm of shielding.
Good article on Wikipedia:
http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator
Dave
but not
On 6/9/13 8:29 PM, Bill Hawkins wrote:
Hi, Thanks in advance.
Since this is a list for precise things, could you make your questions
more precise?
What sort of test cases?
What sort of calculations? Do you mean conversions?
What do you mean by catching an error - where would you
And we received signals from it on ISS at 1400Z this morning (we've got
an experimental software defined receiver doing a 48 hour test right
now). Shiny, new satellite only a few weeks old: I guess it works. At
least we were able to lock. It's still being commissioned, so it's
presumably
On 6/2/13 11:59 AM, Chris Albertson wrote:
Recent talk about NTP servers. It seems the limit to their accuracy is the
quality of the crystal that drives the CPU clock. Most of them make really
good thermometers. I'd like to try and replace the crystal on a Raspberry
Pi with a signal derived
On 6/2/13 12:52 PM, WB6BNQ wrote:
Hello Mark and crowd,
I own one of these and I can guarantee that it CANNOT be moved without changing
the crystal, tweaking a
micro-minature coil value, and changing the firmware. And NO !, the company
would NOT send out the firmware
needed. However, if you
On 6/1/13 8:49 AM, Attila Kinali wrote:
On Tue, 28 May 2013 20:23:06 -0700
Jim Lux jim...@earthlink.net wrote:
The USO's we got for GRAIL from APL have ADEV1E-13 from 1 to 1000
seconds, and then heads up at 1 decade/decade. The lowest ADEV is about
5E-14 at around 50 seconds, but it's pretty
On 6/1/13 10:35 AM, Bob Camp wrote:
Both suffer from people talking about levels (-120 dbc or 1x10^-11) without mentioning
the offset or tau. Since both are highly dependent on the offset or tau that's not a good
thing. My observation is that ADEV is much more likely to be mentioned without
On 6/1/13 1:46 PM, Bob Camp wrote:
Hi
For ADEV, a lot of oscillators have a sort of floor where the
ADEV is relatively constant, say from tau in the range10-1000
seconds, and then it rises up (from thermal effects and such), so
the shorthand is that the number quoted is that floor value
You
On 6/1/13 12:02 PM, Scott McGrath wrote:
True
However with LORAN and to a lesser extent WWVB traceability process
was well/known and documented and had been in place for decades and
was easy to implement correctly With GPS not so much especially
with S/A. Supposedly the new satellites don't
On 6/1/13 2:51 PM, Magnus Danielson wrote:
On 06/01/2013 11:27 PM, Bob Camp wrote:
Hi
On Jun 1, 2013, at 3:34 PM, Magnus
Danielsonmag...@rubidium.dyndns.org wrote:
On 06/01/2013 09:02 PM, Scott McGrath wrote:
True
However with LORAN and to a lesser extent WWVB traceability process
was
On 6/1/13 4:46 PM, Bob Camp wrote:
That is, NIST certifies publicly that WWV is on frequency and on time with
a certain precision. Do I need to go to NIST and pay them to give ma piece of paper that says
this, or can I use their published data?
Remember - the original post (and thus the
On 6/1/13 4:50 PM, Hal Murray wrote:
jim...@earthlink.net said:
It's also the knowledge of the process yield at each step which means you
can stay in business. APL knows how many to start at the beginning to
insure they'll have 4 at the end, 2 years later.
I assume there is a
On 6/1/13 4:52 PM, Magnus Danielson wrote:
So, what was your engineering question, really?
responding to Bob's comment that people just say ADEV 1E-15 without
specifying a tau.
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On 5/29/13 7:37 AM, Mark C. Stephens wrote:
My 3585 is like that too, Unlocked messages until it warms up.
Unless you leave it plugged in, it must keep the oven warm while on standby.
I wonder if this is the case for the 8566 too?
yes.. most of those instruments have a standby where the oven
On 5/28/13 9:29 AM, Bob Camp wrote:
Hi
The cost of a BVA oscillator is primarily a function of the cost of the
blank used and secondarily a function of the resonator processing. You see
numbers in the $200 to $400 range tossed around for the blank (vs $10 for
a good SC blank). The packaged
On 5/26/13 9:00 AM, Chris Albertson wrote:
But for many applications, the inevitable overhead
(power, heat, external components, OS, etc) simply
eliminates the gain of having a better/faster CPU.
Sometimes I end up using a 6 or 8 pin PIC with only
a few lines of code to to solve complex
On 5/25/13 7:22 AM, Bob Camp wrote:
Hi
PIC's have been around for a *long* time. The PIC16's came early on and were
followed by the PIC18's. Both are a bit dated at this point. The PIC24's and
dsPIC33's are actually very similar parts. The PIC33's form a third family
pretty much on their
On 5/25/13 10:55 AM, Chris Albertson wrote:
3) the Pi is almost PC-like and very easy to use. Costs about $40
and requires a HDMI or DVI monitor..
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On 5/25/13 2:10 PM, Paul wrote:
*Jim Lux*
S*at May 25 16:53:50 EDT 2013*
* 3) the Pi is almost PC-like and very easy to use. Costs about $40***and
requires a HDMI or DVI monitor..
A $9 USB to 3.3V serial adapter connects to
the serial console unless you prefer ssh or VNC.
Once you have
On 5/21/13 8:29 AM, Chris Albertson wrote:
The question here, I think was about the day-to-day shaking, not a once in
a lifetime event. Seriously if there was a 1+g acceleration who'd care if
their OCXO was still running under that pile of rubble that used to be a
house. It is the
On 5/20/13 2:43 AM, Attila Kinali wrote:
Oh.. and connect the whole thing to a port on the PC that does _not_
have an internal USB hub.
That's a bit of challenge, I suspect.. A casual look at the PCs I have
around here running windows all seem to have on-mobo hubs when you
check Device
On 5/5/13 1:48 AM, Magnus Danielson wrote:
On 05/05/2013 10:05 AM, Attila Kinali wrote:
On Sat, 4 May 2013 12:36:20 -0700
Tom Van Baak (lab)t...@leapsecond.com wrote:
Rule of thumb: quartz is best short term, Rb or H-maser mid-term,
and Cs by far the best long-term.
Ah.. so it's a
On 5/5/13 8:42 AM, Richard (Rick) Karlquist wrote:
At HP in the 1990's, Len Cutler's group built some experimental
mercury ion standards for USNO (IIRC). They were of the
trapped ion type. BTW, it is important to understand that
the architecture is the key factor, not the flavor of atom.
When
On 5/5/13 10:05 AM, Magnus Danielson wrote:
On 05/05/2013 06:50 PM, Jim Lux wrote:
On 5/5/13 8:42 AM, Richard (Rick) Karlquist wrote:
At HP in the 1990's, Len Cutler's group built some experimental
mercury ion standards for USNO (IIRC). They were of the
trapped ion type. BTW, it is important
On 5/5/13 10:01 AM, Magnus Danielson wrote:
Hi Jim,
On 05/05/2013 03:59 PM, Jim Lux wrote:
On 5/5/13 1:48 AM, Magnus Danielson wrote:
The above is a summary of things collected from a variety of sources,
but I think this coarse walk-through of issues gives some insight as to
what issues pops
On 5/5/13 11:45 AM, Magnus Danielson wrote:
Hi Jim,
On 05/05/2013 07:33 PM, Jim Lux wrote:
On 5/5/13 10:05 AM, Magnus Danielson wrote:
They have been targeting this goal for a very long time. Several
interesting papers is to be found at PTTI, NIST etc.
Yeah.. some years (6 or 7?) ago, John
On 5/5/13 2:49 PM, Magnus Danielson wrote:
I have all the Hg-199 and Hg-202 I need for a few clocks, but in it's
natural mixture. Don't feel like building a separation facility...
Use the quadrupole system you're using as a trap as a mass-spec to do
the separation.
On 5/2/13 5:18 AM, Poul-Henning Kamp wrote:
In message 5182325e.4020...@t-online.de, Volker Esper writes:
Rummor has it that the single piece price in the US is $1475 for just the
CSAC. Weather that's with or without the demo board
And for that price a SRS PRS10 is a better buy, unless you
On 4/30/13 4:18 PM, li...@lazygranch.com wrote:
A bit OT, but back in the day there was what amounted to an X-prize for a real
accurate chronometer for navigation.
Make that way back in the day.
http://en.m.wikipedia.org/wiki/John_Harrison
And he had a heck of a time collecting. I suspect
On 4/27/13 9:40 AM, Gregory Muir wrote:
On Fri, 26 Apr 2013 17:59:21 -0700, Jim Lux wrote:
Total dose will be very small (after all astronauts live in LEO)
So you'd worry about cosmic rays and single event effects.
snip
They fly a lot of unmodified commercial equipment on ISS
On 4/26/13 6:01 AM, Bob Smither wrote:
As many on this list are amateur radio operators the following might be of
interest:
http://www.phonesat.org/
The project asks amateurs to monitor transmissions from cell phones that have
been placed in orbit.
Except that the transmissions are from
On 4/26/13 9:18 AM, Chuck Forsberg WA7KGX N2469R wrote:
On 04/26/2013 06:01 AM, Bob Smither wrote:
As many on this list are amateur radio operators the following might
be of interest:
to track the satellites in real time.
Will radiation fry the cell phones before thy burn up on re-entry?
On 4/23/13 6:54 PM, li...@lazygranch.com wrote:
http://www.aorusa.com/receivers/ar2300.html
Just a FYI.
Interesting..
I see they use the OEM GPS from Garmin. I wonder what kind of DO
performance they get, and whether they actually discipline the
oscillator or just measure it. Since
On 4/21/13 10:37 PM, Stewart Cobb wrote:
Date: Sat, 20 Apr 2013 12:52:03 -0700
From: Tom Van Baak t...@leapsecond.com
To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Subject: Re: [time-nuts] pin-wheel antenna
Message-ID: EB790CDDE52944E1A03608CA6CFCCCA8@pc52
On 4/22/13 12:26 PM, Eric Fort wrote:
Thanks, figured someone who reads this list may be connected there...
not like precision timekeeping is a huge community.
Eric
On Sun, Mar 17, 2013 at 2:53 PM, Magnus Danielson
mag...@rubidium.dyndns.org wrote:
On 03/17/2013 10:47 PM, Eric Fort wrote:
On 4/22/13 3:15 PM, Hal Murray wrote:
dginsb...@gmail.com said:
First, the frequency offset of the microcontroller. I use a built-in
counting timer in the uC which runs at 84MHz to measure the duration between
2 PPS. What I get is ~84008000 timer ticks between two pulses, which
corresponds to
On 4/21/13 5:18 AM, Attila Kinali wrote:
On Sat, 20 Apr 2013 12:52:03 -0700
Tom Van Baak t...@leapsecond.com wrote:
For the rest of you:
http://www.leapsecond.com/images/gps-pinwheel-1.jpg
http://www.leapsecond.com/images/gps-pinwheel-2.jpg
Thanks a lot...
So the design changed slightly
On 4/19/13 7:30 AM, Attila Kinali wrote:
On Wed, 17 Apr 2013 20:16:24 -0700
Jim Lux jim...@earthlink.net wrote:
There's a very nice picture of a pinwheel from Novatel on the back cover
of the March issue of GPS world..
Has anyone a digital (or scanned) copy of that picture?
It's kind
On 4/19/13 11:47 AM, Peter Monta wrote:
Hi Hal,
Why are X-Ray pulsars better than radio pulsars for navigation?
My impression is that it's easier to manage all-sky coverage at x-ray with
a small spacecraft package (I think millisecond pulsars generally emit at
both microwave and x-ray).
On 4/18/13 12:01 AM, Chris Albertson wrote:
If I read the paper correctly you can skip the choke ring if you mount the
antenna on top of a 2 meter or longer mast. Iron pipe comes on 10 foot
lengths. The choke ring is for portable survey antenna that can't be
placed on tall rooftop masts. I
On 4/18/13 4:01 AM, David J Taylor wrote:
An interesting novel use of GPS stray signals
ESA’s retired GIOVE-A navigation mission has become the first civilian
satellite to perform GPS position fixes from high orbit. Its results
demonstrate that current satnav signals could guide missions
On 4/18/13 11:02 AM, Magnus Danielson wrote:
On 04/18/2013 04:01 PM, Jim Lux wrote:
On 4/18/13 4:01 AM, David J Taylor wrote:
An interesting novel use of GPS stray signals
ESA’s retired GIOVE-A navigation mission has become the first civilian
satellite to perform GPS position fixes from
On 4/18/13 12:15 PM, Peter Monta wrote:
I wonder if there's any advantage in combining far-away GPS with X-ray
pulsar navigation (XNAV), which is said to be good to a few kilometers,
though long integration times are needed. For example, the rough system
time from XNAV could enable very long
On 4/18/13 1:40 PM, b...@lysator.liu.se wrote:
All of the high quality GNSS receiver manufacturers have their own
version of correlator that try to mitigate multipath. See for example
this Ashtech-document (for a ca 10 year old L1 only receiver (DG14/16)).
On 4/17/13 4:26 AM, Bob Camp wrote:
Hi
The description from their tech guys is Very high gain front end. It's a saturating
amp rather than a comparator.
I thought the whole point of fast ECL logic was that it never saturated.
Of course these days, one might have very fast saturating logic
On 4/16/13 9:17 PM, Lachlan Gunn wrote:
A few reasons:
- I am interested to see what can be done with the statistics of an
ensemble of oscillators---in particular, whether the additional measurements
can be used to get a timescale that is more stable than just GPS and OCXO or Rb.
-
On 4/17/13 12:18 PM, Chris Albertson wrote:
Another way to ask this question is what is the effect of a small
deviation form the ideal dimensions?
If we assume deviations of about 1/20th of a wavelength are OK then we can
allow about 1cm of dimensional error. Almost anyone using simple hand
There's a very nice picture of a pinwheel from Novatel on the back cover
of the March issue of GPS world..
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On 4/15/13 10:40 PM, bg wrote:
Chris,
Chokering is not needed. Measured quality antennas are listed at
http://www.ngs.noaa.gov/ANTCAL/
Or at
http://www.geopp.de/index.php?sprachauswahl=enbereich=0kategorie=34artikel=62
/Björn
A lot of the antennas on that list are
On 4/16/13 11:04 AM, Attila Kinali wrote:
On Mon, 15 Apr 2013 23:00:49 -0700
Jim Lux jim...@earthlink.net wrote:
the effect of a strong multipath (which is what the choke ring
suppresses) would be a LOT bigger than that..
Uhmm.. to my understanding, this is not quite true.
The choke ring
On 4/16/13 5:19 PM, Sarah White wrote:
I just have to ask though... cake pans? really? I can't imagine it would
even be possible to modify a cake pan with enough accuracy to get a
usable antenna.
Sure.. cake pans, like other stamped goods, are actually pretty high
precision, because they're
On 4/16/13 8:28 PM, Mark C. Stephens wrote:
Actually, before I plugged the GPS antenna into the second unit, I checked out
where it last called home:
LAT N 36:01:05.225
LON E 128:41:48.761
HGT+1214.14 m (MSL)
Mt Palgong, according to Google Earth
Lots of transmitter towers up
On 4/15/13 1:48 PM, Dr. David Kirkby wrote:
On 04/15/13 04:39 AM, Jim Lux wrote:
Inexpensive USB spectrum analyzer.. http://www.signalhound.com/
It's not that inexpensive. I assembled a 22 GHz spectrum analyzer based
on the HP 7 modular measurement system for about the same money.
New
On 4/15/13 8:36 PM, Chris Albertson wrote:
On Mon, Apr 15, 2013 at 8:23 PM, Tom Van Baak t...@leapsecond.com wrote:
I'd be curious what level of improvement is possible. It will depend on the
receiver and the antenna. I believe the NIST project uses fancy antennas
but normal M12 receivers. So
On 4/15/13 9:27 PM, Tom Van Baak wrote:
NIST SIM GPS common view pinwheel
described in one of the NIST reports as an aperture coupled slot fed
array that is better than a patch, but not as large and heavy as a choke
ring.
W. Kunysz, 2000, “High Performance GPS Pinwheel Antenna,” in
On 4/15/13 10:22 PM, Jim Lux wrote:
On 4/15/13 9:27 PM, Tom Van Baak wrote:
NIST SIM GPS common view pinwheel
described in one of the NIST reports as an aperture coupled slot fed
array that is better than a patch, but not as large and heavy as a choke
ring.
W. Kunysz, 2000, “High
Inexpensive USB spectrum analyzer.. http://www.signalhound.com/
I think it has the ability to capture raw samples, too. (the BB60
definitely does.) They have a 10MHz ref input.
The spectrum analyzer has a phase noise feature
Phase Noise Plot
: Displays the phase noise amplitude, in dBc/Hz,
On 4/8/13 9:59 AM, Alan Melia wrote:
Hi all an interesting problem you may have encountered, I want to use a
GPS frequency standard inside a building with no opening windows
(opening windows are known as air conditioning in the UK :-)) )
This is part of a two day amateur microwave conference so
On 4/8/13 2:12 PM, Tom Van Baak wrote:
Alan,
Google for words like GPS re-radiator or GPS repeater. There are also units on
eBay. If not to buy, at least to study examples.
The one I have is made by www.gpssource.com but it seems you could build one
yourself. It's easy to test by looking at
On 4/6/13 6:08 AM, Lester Veenstra wrote:
Any TimeNutter worth his/her salt can do that..right!
$100 Presto 23 qt canning style pressure cooker, electric heating
elements, thermocouple probes, some fiberglass insulation to reduce
conductive losses.
Do it in your backyard and have a straw
On 4/6/13 6:55 AM, Bob Camp wrote:
Hi
On Apr 6, 2013, at 9:39 AM, Jim Lux jim...@earthlink.net wrote:
On 4/6/13 6:08 AM, Lester Veenstra wrote:
Any TimeNutter worth his/her salt can do that..right!
$100 Presto 23 qt canning style pressure cooker, electric heating elements,
thermocouple
On 4/6/13 12:44 PM, Ivan.Cousins wrote:
Here is a related Arduino project.
http://www.pjrc.com/teensy/td_libs_TinyGPS.html
This is where I get my Arduino boards.
I like the 32 bit Arduino processor for some applications.
http://www.pjrc.com/store/teensy3.html
I'm a big fan of their
On 4/3/13 11:32 PM, gary wrote:
Can anyone translate this to English. OK, it is English, but you know
what I mean. It is supposed to be some new time service.
http://rts.igs.org/access/
Not exactly time service.. this is one of the entry points to do high
performance GPS geodesy. Of
On 4/4/13 12:51 AM, gary wrote:
Isn't this what WAAS does?
http://igs.bkg.bund.de/ntrip/about
Yes..
There's lots of ways to get real time (or near real time) correction
data. WAAS is but one. TASS (experimental) is another. There's various
and sundry local High Accuracy Reference
On 4/4/13 7:52 AM, Herbert Poetzl wrote:
On Thu, Apr 04, 2013 at 02:32:09PM +, Mark C. Stephens wrote:
I wanted to have a look at what the Z3805A puts out on Port 2.
I can see the LEDS flickering on the BOB so its saying something.
I connected up a terminal program set to 96008N1 and it
On 4/1/13 3:06 PM, Bill Hawkins wrote:
Looking for a long, thin horizontal clock display for use above or below
a flat screen TV.
Tried searching for bar clock and got a lot of useless hits.
If you're bulding it.. Arduino is your friend.. there's tons of LED
displays of all shapes and
On 3/30/13 2:58 PM, Lizeth Norman wrote:
What a bunch of hooey. Another so called expert wasted hours of my time
because he can't be bothered to either note that code is buggy or just
can't be bothered..
If you don't want to release it, then don't. If you do and it's a POS,
Expect emails.
On 3/29/13 9:01 AM, Bob Camp wrote:
Hi
Too much tuning range is easy enough to fix. Use a pot to set it on frequency and then
hook it to the rest of the stuff with a fixed resistor. The gotcha would be
if the poor thing drifts so much that it *needs* the wide range to stay in lock.
My guess
On 3/30/13 5:31 AM, Bob Camp wrote:
Hi
If you go back into the papers from the early 1980's there is one where they
used a high gain antenna and no knowledge of the coding scheme to pull timing
off of GPS. I believe it was at White Sands, but that could be wrong.
One can just run it into
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