Hi
There are a very small number of signal generators that *might*
help when measuring phase noise on a good source. The “rest
of them” are very much in the “don’t bother” category. Just which
one is in the “maybe” category depends a lot on your frequency
of interest. None of them seem to be
yes there are much better signal generators out there, that frequency
doubler tuning circuit is for religious people only -- you need to be
able to believe, that it could work
73
KJ6UHN
Alex
On 7/11/2022 12:24 PM, Dave B via time-nuts wrote:
On 11/07/2022 08:30,
Hi
Regardless of what you call the “ 1 Hz normalized noise “ of a digital
phase detector, it does predict what the noise floor does on it as the
reference frequency is changed over some reasonable range. This has
been demonstrated a lot of times and on a lot of different parts.
Based on a
Anyone in Canada planning on buying the HMC984LP4E from Digi-Key, they
state:
Last Time Buy Date: 7/31/2022
They had 42 in stock before I ordered. I bought 5, which gives free
shipping(FedEx).
Mike
___
time-nuts mailing list --
On 11/07/2022 08:30, time-nuts-requ...@lists.febo.com wrote:
I also measured a Marconi 2022 signal generator and it was possible to
lock but the phase noise was terrible with strong factional PLL spurs.
Indeed, those signal generators are renown for having "some rather
interesting" spectral
to Magnus:
I was not saying anything about measuring noise. I only stated that a DBM
has a square wave output at twice the signal frequency.
If you are measurng OCXO noise, you might be interested in a method I just
described to Bob.
Thanks,
Mike
___
To Bob kb8tq
Figure Of Merit sounds like a useless number. I have a different
approach that yields immediate and useful results. Before I explain
my method, let me introduce myself.
In 1970, I invented, and Memorex patented, the original
zero-deadband phase-frequency
Hi
These days there are folks who make a living tracking down interference
sources in the vicinity of ports and airports on a contract basis. Many of
the issues are navigation related. Some of it is GPS. Some is other stuff
( like 5 GHz WiFI and radar …)
Bob
> On Jul 11, 2022, at 1:28 PM,
Andy Talbot said:
> I also heard a case of a GPS antenna going unstable, oscillating and taking
> out most of the boats in a marina. The Radio Communications Agency (as our
> enforcement body was then, before it became Ofcom) had to be called out to
> identify the problem.
There was an
On 7/11/22 12:48, jeanmichel.friedt--- via time-nuts wrote:
for what it's worth ... the UK gov. is nice enough to warn about GPS jamming
exercises
https://www.ofcom.org.uk/spectrum/information/gps-jamming-exercises
not sure about the US of A announcements on such activities. At least in France
On 7/11/2022 8:43 AM, Andy Talbot via time-nuts wrote:
I also heard a case of a GPS antenna going unstable, oscillating and taking
out most of the boats in a marina.
There have also been several cases of cheap active TV antennas doing the
same thing. There was a case 10 or more years ago that
Google 'GPS testing notices'
On Mon, Jul 11, 2022 at 1:15 PM jeanmichel.friedt--- via time-nuts <
time-nuts@lists.febo.com> wrote:
> for what it's worth ... the UK gov. is nice enough to warn about GPS
> jamming
> exercises
> https://www.ofcom.org.uk/spectrum/information/gps-jamming-exercises
>
for what it's worth ... the UK gov. is nice enough to warn about GPS jamming
exercises
https://www.ofcom.org.uk/spectrum/information/gps-jamming-exercises
not sure about the US of A announcements on such activities. At least in France
I have never seen such warnings.
Best, JM
--
JM Friedt,
Hi
Are all the receivers the same type / model? If so what are they? Various
receivers made over the last 20 years have some “issues” that can pop up.
Is the antenna gain properly matched to the needs of the receiver? Some
are designed for a “target gain” of 20 db, others 30, some 50. Match a
The u-blox SAW filtering is great. We've carried out various RF
measurements with +40 dBm EIRP at 2.53 and 3.75 GHz with some u-blox
ANN-MB within <2m of the Tx antennas. While we haven't conducted
in-depth comparisons with a superior ground-truth, my current conclusion
is that the u-blox RTK
With the new 5G hardware, we are seeing all manner of new interference,
some of it quite broad-band. A good antenna with sharp SAW filter may
help, but not if the emmisions are in-band. Besides broad-band, there
also can be 2nd harmonic emissions that cause interference. We had this
problem
There is a 3G/4G Supplementary Downlink allocation at 1492MHz in some
countries. Close enough to cause problems.
Andy
www.g4jnt.com
On Mon, 11 Jul 2022 at 14:40, paul swed via time-nuts <
time-nuts@lists.febo.com> wrote:
> Skipp
> I am aware at least in the US that there is the possibility
I have had one, and possibly two, low cost active antennas go unstable and
start oscillating. These are the magnetic car mount type with a ceramic
patch antenna. The ceramic patch has quite a high Q and determines the
frequency the unstable RF front end takes off at - which is obviously at
Skipp
I am aware at least in the US that there is the possibility of 5G
interference along with newer possible bands that 5G can use. I have read
several articles in a publication called GNSS.
Thats why I am using wwvb at 60 KHz. Humor intended.
Regards
Paul
WB8TSL
On Mon, Jul 11, 2022 at 8:49
On 7/10/22 4:19 PM, skipp Isaham via time-nuts wrote:
Hello to the Group,
I'd like to get some opinions and war stories regarding GPS reliability at
high RF level and elevation locations.
Background: Three different hill-top GPS receivers, all different types, using
different antennas mounted
On Sun, July 10, 2022 6:19 pm, skipp Isaham via time-nuts wrote:
> Background: Three different hill-top GPS receivers, all different types,
> using
> different antennas mounted on an outside fixiture, plain view of the open
> sky,
> all stopped working.
>
> Test antennas were brought in and
Hi Skipp -- there is a lot of info about interference mitigation in the u-blox
integration manual for the ZED--F9T (available under the docs at
https://www.u-blox.com/en/product/zed-f9t-module). It might give you some
clues, and I think might also point to another u-blox app note on the topic.
Hey Skipp!
A couple of thoughts…
Why do you need an amplified antenna in a high and open spot, unless the coax
run is longer than about 40’?
Is it practical to move one of the existing antennas away from the current
location as a test to see if it’s a failure vs overload? Assuming it is
Can anyone tell me what the group of four LEDs in one corner of the
E1938 board indicate? There is no indication of function on the schematic.
Thanks for any enlightenment!
Dan
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe
Hello to the Group,
I'd like to get some opinions and war stories regarding GPS reliability at
high RF level and elevation locations.
Background: Three different hill-top GPS receivers, all different types, using
different antennas mounted on an outside fixiture, plain view of the open sky,
25 matches
Mail list logo
