Wayne very good progress. You can actually feed the loop coild that exists
with the cap it should resonate.
Thats my plan at least.
Regards
Paul
WB8TSL
On Thu, Aug 30, 2018 at 9:44 PM, Wayne Holder
wrote:
> I've had some luck improving things with my ATTiny85-based WWVB Simulator
> design by
On Thu, Aug 30, 2018 at 2:03 PM jimlux wrote:
>
> On 8/29/18 6:55 PM, John Hawkinson wrote:
> > Continuing reference to what is "legal" or "the law" is very confusing to
> > me because no one has cited any statues, regulations, or case law.
> >
> > What's the basis for these claims about legal
On Thu, Aug 30, 2018 at 12:59 PM Bob kb8tq wrote:
> There most certainly was a lot of “stuff” in orbit by that time. If there was
> a mass die off of satellites, you would not have to look hard to find out
> about
> it.
Probably not as many as there are 3 decades later, but of course.
Hi
The original “we cracked GPS” paper back in the 1980’s (that unlimitedly lead
to the end of SA)
used a medium sized dish ( think of the good old C-band antennas) to pick out a
single sat.
Bob
> On Aug 30, 2018, at 9:54 PM, Brooke Clarke wrote:
>
> Hi Gregory:
>
> I wonder if anyone has
I once bought a pair of low power 315 MHz TX/RX modules and was going to try
them in a model rocket + GPS. I tested them with a serial port and they had a
range of a couple thousand feet at 1200 BPS. But when the transmitter was
connected to the GPS, the GPS lost lock... turns out 315 MHz *
Hi Gregory:
I wonder if anyone has tried using a small parabolic dish, like used for Free To Air satellite TV and aimed it at a GPS
satellite track or at a WAAS geostationary satellite using a feed antenna with reverse polarization from a normal GPS
antenna?
http://www.prc68.com/I/FTA.shtml
Hi
….. ok, so you are dealing with city wide jammers that take out all of New York
City on a daily basis?
Again, that was the original example tossed out. “A cigarette pack sized jammer
that takes out an entire
city”. A jammer with that sort of range is an easy jammer to spot.
Somehow I
Just ask the NY Port authority how ‘easy’ knocking these jammers offline is.
Usually done by vehicle to vehicle inspection with a SA.
And yes the day job all too frequently searching for and identifying
interference sources.
One of the more interesting ones was a halogen leak detector wiping
Hi
Since timing receivers are actually going to prefer high angle sats, an antenna
that rejects
close to the horizon is a pretty common thing. Enhancing that sort of rejection
doesn’t take
a lot of effort.
Bob
> On Aug 30, 2018, at 7:05 PM, Gregory Maxwell wrote:
>
> On Thu, Aug 30, 2018
Hi
Actually it’s pretty simple to track down that sort of jammer ….. and yes, the
gear to do it
is out there in quantity.
Bob
> On Aug 30, 2018, at 6:51 PM, Scott McGrath wrote:
>
> As Brooke notes while low frequency jammers are possible, practicality is
> another matter, All it takes
Before retiring I did some field work on the Tomahawk AGR
(https://www.raytheon.com/capabilities/products/gps_anti-jam)
Wes N7WS
On 8/30/2018 4:05 PM, Gregory Maxwell wrote:
However, the short wavelengths of GPS make beam forming a reasonable
countermeasure against jamming.
Is there a translation of this anywhere?
Don
Sweden were much more serious about it:
http://www.antus.org/RT02.html
Tl;drs:
They erected 9 200m tall Loran-C class antennas each driven by
a Loran-C transmitter with an advanced degree which could jam
Loran-C or Chayka.
They even
Congratulations, Magnus! Fellowship is next.
On Thursday, August 30, 2018, Magnus Danielson
wrote:
> Hi Bob,
>
> On 08/30/2018 10:33 PM, Bob kb8tq wrote:
> > Hi
> >
> > Magnus … do you have some news you might want to share with the group?
>
> Oh, well, sure:
>
> Today I received a nice email
On Thu, Aug 30, 2018 at 9:43 PM Brooke Clarke wrote:
> I would disagree in that ease of jamming/spoofing is strongly related to
> wavelength. That's because antenna efficiency
> goes down as the size of the antenna gets smaller than 1/4 wave.
> So, it's easy to make a GPS jammer (1,100 to
As Brooke notes while low frequency jammers are possible, practicality is
another matter, All it takes to jam a city scale area is a box the size of a
pack of cigarettes.Because the GPS signal is very, very weak.
As an intentional denial put a couple hundred on stray animals.Now track
On Thu, 30 Aug 2018 at 14:03, jimlux wrote:
>
> There may well be a law in the United States, probably buried in some
> enabling or appropriating bill, that says "The Department of Commerce
> shall provide national standards for mass, time, voltage, etc." but
> that doesn't say "and all
Congrats Magnus!
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
p...@freebsd.org | TCP/IP since RFC 956
FreeBSD committer | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.
Hi
Well, designing jammers on a public forum is an “interesting” thing to do…..
With WWVB, you are fine with a “near field” solution. You don’t need something
that propagates for
miles and miles. The other thing you have in your favor is that coming up with
a KW at 60 KHz is
quite easy. All
Hi Bob:
I would disagree in that ease of jamming/spoofing is strongly related to wavelength. That's because antenna efficiency
goes down as the size of the antenna gets smaller than 1/4 wave.
So, it's easy to make a GPS jammer (1,100 to 1,600MHz) since a 1/4 wavelength is a few inches,
Hi
Magnus … do you have some news you might want to share with the group?
Bob
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Hi
When infastructure GPS *does* get jammed these days that source gets tracked
down a lot faster
than a month or so. Anything that goes on for more than a day gets booted up
pretty high
pretty fast. Indeed I’ve been in the middle of that more than I would have
wished to be …..
The same sort
The UnusualElectronics Chronverter with NEO 6 GPS, 9.6 MHz oscillator.
dividers and such are all up and working. Watching GPS time, Spectracoms
and Truetime clocks all tick at the same time while listening to WWV.
exactly as they should. Now I have a alternate for wall clocks should WWVB
be
The port of Long Beach CA was jammed wrt GPS for several months by a
malfunctioning 29.95 TV preamplifier on a boat.
GPS was completely unusable when this unsuspecting guy was watching TV on his
boat.
He had quite the surprise when the coasties with guns showed up.
The fact is civillian GPS
Hi
Same basic problem with WWVB. If you were using it as a reference, you timed
your
data collection to avoid the transition periods. You got both phase shifting
and the
amplitude took a dive. Neither one was going to help you make a precision
measurement.
In addition there are various
Hi
> On Aug 30, 2018, at 12:58 PM, Peter Laws wrote:
>
> On Mon, Aug 13, 2018 at 8:52 AM Peter Laws wrote:
>
>
>> I have yet to hear anyone make a case for retaining the HF system that
>> isn't backed by nostalgia.
>
> Still looking for this. Most of the "OMG IF WWV GOES AWAY MILLIONS
>
Hi
With the Loran boxes, you were doing well to get down to the 100 ns level. When
you did, it always was a
questionable sort of reading. More or less - is this real??? I spent a *lot* of
time watching that data ….
Estimating what WWVB is doing over long baselines as the weather changes is
On Mon, Aug 13, 2018 at 8:52 AM Peter Laws wrote:
> I have yet to hear anyone make a case for retaining the HF system that
> isn't backed by nostalgia.
Still looking for this. Most of the "OMG IF WWV GOES AWAY MILLIONS
WILL DIE" posts (elsewhere, not here ... quite ...) are the type of
Hi, Gunn diodes idea sound like an interesting experiment. For the moment I
won't be able to as I don't have the time, but I'll definitely keep this idea
in mind. Thanks for sharing it!
Dan
PS. Always too busy, never enough time. Perhaps it's why messing with clocks..?
-Chickens are more
On 8/30/18 8:15 AM, Mike Bafaro wrote:
According to what I have heard the 60KHz WWVB carrier is guaranteed accurate to
the atomic standard and is considered traceable. I remember when I was in the
Navy years ago I remember taking our unit's HP5245L for calibration and they
used a VLF
One does not get the same instantaneous accuracy that one gets from GPS but
with a long baseline the offsets to your site can be determined.With eLoran
you can get similar levels of accuracy as the old Austron monitors used to
prove
Content by Scott
Typos by Siri
On Aug 30, 2018, at
Hi
WWVB as transmitted ( = right at the input to the antenna) is a wonderfully
stable signal. As soon as
that signal hits the real world things start to degrade. Propagation between
transmit and receive sites
is a big deal, even at 60 KHz. On top of that, there is a *lot* of manmade
noise at
Hi, if its of any help I (still) have a box of goodies including some 10 and 22
GHz Gunnplexers. would the diodes be of any use?
The RX (IIRC its a varactor) diode is structurally very similar to an SRD,
maybe possible to adapt it if as I expect the resonance is tuned to near 6 GHz
by
Management signed a PO for the previously "unneeded" Symmetricom units that had
been requested a year earlier the next day...
Jim
From: time-nuts on behalf of Scott McGrath
Sent: Thursday, August 30, 2018 11:24:03 AM
To: Discussion of precise time and
Bingo - we have a a Winner!!!
In a prior life as an architect at a northeastern we had Cs clocks, multiple
GPS based NTP servers and CDMA NTP servers as TIME was the public key for all
the crypto systems the Cs clocks were there in case GPS ‘went away’ for any
reason and with service
Hi
This is not so much a GPS issue as a system design issue. GPSDO’s are used to
“smooth over” bumps in a lot
of systems out there. At the timing levels required by ATM or authentication
setups, you can go a *long* time
running on a GPSDO. It’s not a matter of GPS, it’s a matter of doing
Time is the public key for a lot of the crypto that runs on networks.
Any large university or corporation has multiple GPS based time sources and
compares them to others...
Back in the mid-1980's a fire in a CO in East Lansing, MI and a backhoe in
Jackson, MI took out the Internet
Gentlemen,
Some days after I fired up my 5065 after initial repair of the RV Cavity,it
became unstable and lost lock.
No output signal from the A3 Multiplier Assembly.
Q9 (final) was dead and was replaced with a 2N5109to which I added a thermal
pad between the case and the PCB.
Q5
On Thu, Aug 30, 2018 at 9:42 AM, Scott McGrath wrote:
> Um no
>
> Will the internet continue to route packets without precision timing yes
> it will, Yes the lambdas will stay lit on fiber but the ATM transport that
> runs on the lambdas will fail (note DSL is simply an ATM VC over copper).
>
Um no
Will the internet continue to route packets without precision timing yes it
will, Yes the lambdas will stay lit on fiber but the ATM transport that runs
on the lambdas will fail (note DSL is simply an ATM VC over copper). and other
timing dependent services will fail
Will many
Since propagation issues quickly degrade both frequency stability and time
accuracy, I see little point in worrying about the difference between UTC
and UTC(NIST).
Of greater interest should be the meaningfulness of time transfer obtained
with
NIST's TMAS service. It is apparently referred to
For anyone trying out my ATTiny85 code, I've done some additional tests and
find that placement of the antenna near the clock is very finicky and, so
far, the only way to get a reliable decode of the time in the clock is by
using a scope to monitor the demodulated output and then moving the
I was under the mistaken impression that WWV/WWVB had some type of
direct line to NIST in Boulder. However, when I toured the facility in
Fort Collins earlier this year, I learned otherwise. The signals and
carriers are derived/synced from "ordinary" HP (possibly some more
recent
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