Corby,
What's the H flow rate control doing when the IF level goes down, or
increases, depending?
Prior to retirement, I was the "Keeper of The Clock" at my job, which
entailed riding herd on
our Symmetricom H-Maser (among other things). At one point about five
years ago, the
IF amplitude began
in
a matter of days due to in-diffusion from the high pressure He atmosphere.
They
had to order custom vidicon tubes made of special glasses for which He
diffusion
was much lower.
Dana
On Tue, Aug 14, 2018 at 4:21 PM, Attila Kinali wrote:
> On Tue, 14 Aug 2018 14:23:56 -0500
> Dana Whitlow
Arecibo did a kind of cute trick with their distributed 1PPS. The one
second pulses were of one length
(100 ns as I recall), but the 10 sec boundaries had the pulses be about
twice that length. One could carry
this scheme to considerable lengths as desired.
Dana
On Tue, Aug 14, 2018 at 4:00
One might also do some trials based on comparing ADEV results between a
clean carrier signal
and ones corrupted with varying degrees of FM (for example), to get a feel
for the problem. If
nothing else, one ought to be able to get some feel for the sensitivities
involved.
Dana K8YUM
On Mon,
How exactly does one get submillisecond time of day precision with a
sextant?
(even if sticks and pebbles are thrown into the mix)
I'd say more like ~1 sec precision on a really fine day, it the sextant is
wielded by
a skilled and practiced operator who has apriori knowledge of his location.
And
Note to all;
Be cautious about getting time of day from consumer GPS products. All that
I have encountered
(so far) exhibit T.O.D. errors up to a few tenths of a second, and the
error is not repeatable from
session to session. Some do have PPS outputs, which are typically claimed
to provide
er is reading this and getting the idea to make a GPS to
> WWVB timecode radio transmitter, clever gent that he is. :-)
>
> Best Wishes,
> Craig
> KI7CRA
>
> > On Aug 11, 2018, at 7:48 PM, Dana Whitlow wrote:
> >
> > I fear the worst. The line in the webs
> may be a few still in production that don’t.
>
> Without full doc’s on a GPSDO, you really don’t *know* where the PPS is
> set to originate. It may
> be coming from the disciplined clock on the board. It also *may* be coming
> straight from the GPS
> module. There are indeed
I fear the worst. The line in the website simply stated something like
"shutting down
the transmitters in Colorado and Hawaii", which would seem to include the
whole
enchilada.
For the wall clocks, GPS should work well if people are willing to go to
battery-
backed AC power. But not so good for
Could someone please define and explain the term 'hanging bridge' in this
context?
Thanks,
Dana
On Tue, Aug 14, 2018 at 7:02 AM, Azelio Boriani
wrote:
> Hanging bridges out of a GPSDO's PPS? Interesting... time to try to
> setup a measurement and see the relation between the GPS's PPS
that can drive a 1 transistor or diode modulator.
> Regards
> Paul
> WB8TSL
>
> On Fri, Aug 24, 2018 at 3:14 AM, Dana Whitlow
> wrote:
>
> > Is there a schematic published for the Chronverter? I agree with Didier
> > that the
> > OOK issue *ought *
Is there more of it? What I see makes no reference to WWVB.
Dana
On Fri, Aug 24, 2018 at 1:10 PM Graham / KE9H wrote:
> Here is the URL of a petition to maintain funding of WWV, WWVH, WWVB.
>
> Only currently at about 7 percent of the number required for a response
> from White House.
>
>
>
Not having the coordinates in hand, all I can do is suggest using Google
Earth (or Maps)
and look for suitable antenna farm(s).
Dana
On Tue, Aug 21, 2018 at 12:05 PM Mark Sims wrote:
> Lady Heather v6 has a command (SD) that estimates the propagation delay
> (and distance) between your
With the watch being physically close to the faux WWVB "transmitter", one
is in
the so-called "near field" regime, where the field strength (V/m) falls as
the inverse
cube of the distance. If one is putting the watch, say, within a few
inches of the
transmitter, reliable reception should be
er,
> > > you might even have issues from the guy two houses away …...
> > >
> > > Bob
> > >
> > > > On Aug 26, 2018, at 1:08 PM, paul swed wrote:
> > > >
> > > > Agree with the conversation. With respect to neighbors when the day
>
Be watchful about the black epoxy. It may just be a dyed (otherwise
clear) epoxy,
and some of the black dyes in common use pass near IR quite readily. This
would
probably be most troublesome if the ambient light source were of the
incandescent
persuasion.
Also, small diodes in clear packages
Did the original '4046 include the anti-backlash fix?
Dana
On Saturday, July 21, 2018, Dr. Ulrich L. Rohde via time-nuts <
time-nuts@lists.febo.com> wrote:
> Obsolet by today’s standard
>
> Sent from my iPhone
>
> > On Jul 21, 2018, at 10:44 AM, Poul-Henning Kamp
> wrote:
> >
> > Clearly not
I'm thinking about if/when "the big one hits" and takes out most or all of
the GPS
sats, cell phone systems, etc.
Then the time required to reboot up to a reasonable level of technology
might turn
out to be limited by our ability to determine time and freq somewhat
accurately. The
better we can
Scott & John,
Do either of you have any activity by "Light Squared" (or whatever it's now
called) in your area. Jamming does not always have to be in-band to be
effective.
Dana
On Tue, Sep 4, 2018 at 1:11 PM Scott McGrath wrote:
> My TrueTime DC-XL has lost lock since yesterday as has my
Paul,
You really don't want to be building an antenna that radiates energy, which
is a far-field
concept. In your case, at 30 ft range, you're so far inside the near field
that all the
antenna articles in the world won't help, since they address radiating into
the far field.
That's what WWVB
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
Don, I've noticed that in general IEEE retains copyright on most stuff they
publish.
I've been a member for more than 20 years, and this galls me. For an
organization
that purports to be for the good of mankind, they seem awfully stingy with
the
information they gather. But if you do acquire
If you can get access to a 2-channel 'scope, try it instead of a TIC
so you can get some clue as to what's happening. I suspect that one
component of the problem is that the supposedly Hi-Z input of the
counter really isn't but has a stub of unterminated cable between the
input connector and
Jerry,
Please contact me off-list. I have questions, and might be very
interested in your T'bolt.
Dana k8yumdoo...@gmail.com (830) 896-6712
On Tue, Oct 30, 2018 at 5:05 PM Jerry wrote:
> Subject: Tbolt GPS for sale
> I am selling my Trimble 10 MHz Thunderbolt GPS disciplined
related to making
> repeatable measurements using scopes. I'm gonna see if I can find some of
> those. I remember some crazy looking telco standard that required measuring
> amplitude noise on time scales measured in weeks.
>
> Tim N3QE
>
> On Mon, Oct 1, 2018 at 8:47 AM D
David Van Horn,
You're on the right track, but what would you do about those pesky leap
seconds?
Dana
On Fri, Sep 28, 2018 at 2:48 PM Artek Manuals
wrote:
> H Farce-Book hadn't considered that approach .. some sort
> of (ready for this )
>
> "subliminal millennial mind control"
Tom,
Divide the 10 MHz down to 2 MHz in the usual way, then multiply by 8
with a cascade of three analog freq doublers separated by fairly narrow
bandpass filters. Caveats: Would need four filters total along the path
to get rid of unwanted frequency components, gain distributed along
the path
lloscope-based measurements of frequency
> stability
> >
> > This sounds interesting enough and I would appreciate any notes or
> insight on doing this. I have a PRS10 and several GPSDOs that I would like
> to evaluate for performance on my scope.
> >
> > Many thanks
I cheered when I saw Dave B's "silly question", for
then I realized that I'm not the only one who likes
to measure things with an o'scope.
I had purchased a GPSDO a few weeks before and
had been observing its behavior relative to a free-
running Rb by watching 10 MHz sinewaves drift with
respect
Isn't it the case that computer clocks these days are subject to two
influences that make them worthless for timing?
1. Deliberate random FM to spectrally spread RFI leakage.
and
2, Wild variations of clock speed according to usage needs of the moment,
in order to reduce average power
Question:
Supposing you buy a bundle of a couple of dozen fibers inside one outer
jacket: Can
anyone give me an idea of how well the individual fibers are likely to be
matched in
delay, and in delay tempco?
Dana
On Sun, Sep 2, 2018 at 1:46 PM Poul-Henning Kamp wrote:
>
>
> In
my PRS-10, for example, although I've
seen no evidence of unstable timing results. But in this arena,
it generally pays to be fussy.
Dana Whitlow
On Fri, Sep 28, 2018 at 7:06 AM Bill Byrom wrote:
> On Thu, Sep 27, 2018, at 11:55 AM, Dave B via time-nuts wrote:
> > Triggering a dual beam 's
Has anybody tried the AD8003 (triple video line driver amplifier) for use as
distribution amplifiers? It looks to me like this part might be a decent
choice.
On caveat, however: don't succumb to the temptation to reduce the circuit
bandwidth by putting a capacitor across the feedback resistor-
Ulrich,
Is it OK for us to forward the URL for your "Noise" paper to others
outside the time-nuts group?
Thanks,
Dana K8YUM
On Tue, Dec 11, 2018 at 9:24 AM Ulrich Rohde via time-nuts <
time-nuts@lists.febo.com> wrote:
>
>
I wonder if that "insult" was the inspiration for thermometers designed
around quartz resonators.
For more details on the new "accelerometer", one might want to read:
I generated a spiral plot of phase and amplitude covering about 3 minutes of
WWVB last fall. It's a good-size file, around 2MB as I recall.
Should I send it?
Dana
On Wed, Dec 5, 2018 at 8:56 AM jimlux wrote:
> https://www.rtl-sdr.com/tag/vlf/
>
> a fair number of examples -
>
> As I
I'm considering purchasing one of these units, but would like
to know just how bad/good is bad/good before I leap. I'd get
the most useful info for the case of all modulations OFF,
"perfect" external reference, and for a reasonable assortment
of RF frequencies (or one frequency plus a statement
My PRS-10 (a telecom version) runs with a heatsink temp of around 55C of
a bit less. But some areas of the case actually run a few deg hotter than
that.
Dana
On Fri, Nov 16, 2018 at 3:49 PM Mark Sims wrote:
> My case temp runs around 70C with the SRS heatsink installed. If you
> don't have
I want to run about 4 separate GPS units of disparate
manufacture from a single antenna. My plan is to
provide power for the antenna via a bias tee (power
inserter) at the bottom end of the antenna's cable, then
use an isolating splitter on the receiver side of the bias
tee to split to the
I was moved to check on the terms "decimate" and "downsample" to see what
their
relative meanings are, and was disappointed to see that they are virtually
the same.
Perhaps Tom would be willing to discuss this point and suggest meanings to
be used
in this group.
Dana
On Thu, Jan 10, 2019 at
I'm confused...
I see two separate cases here:
Case A: you simply throw away samples, keeping only every nth sample,
without
regard for the frequency content of the original signal.
Case B: you first perform appropriate anti-aliasing filtering on the
original signal, and
only then throw away
Frequency dividers can be pretty low noise, if you choose the right class
of logic. I remember that
at one time in the distant past, LSTTL was considered king. Unfortunately
I've been out of touch
with frequency dividers long enough to be ignorant of what works well today.
i'd suggest trying
I'd been thinking, in an admittedly non-rigorous sort of way, about this
matter for some years.
As I see it, it is certainly true that the phase of an oscillator's output
is a continuous funciton
of time. It could be described as a continuous ramp, whose slope
corresponds to the frequency,
and
lot of years. In general faster saturated logic produces lower noise
> floors than slower
> logic.
>
> Bob
>
> > On Sep 16, 2018, at 4:33 PM, Dana Whitlow wrote:
> >
> > I'd been thinking, in an admittedly non-rigorous sort of way, about this
> > matter fo
Could it really be 4.194304 MHz (2^22 Hz)?
Dana
On Sun, Mar 31, 2019 at 5:03 PM Neville Michie wrote:
> Hi,
> I have a Philips quartz clock that runs on 4.19 MHz.
> In spite of the high frequency it still runs for years
> on a C cell.
> Can any of the quartz crystal gurus explain why this
>
Relative to Harrison's method of star position measurement and timing, and
the
possible effects of diffraction thereof:
Hanbury Brown's book "The Intensity Interferometer" may provide some useful
insight about various error sources, even though in a different context,
that of
measurement of a
I remember often reading that if you run a 'lyt at a voltage much reduced
from its rating,
the oxide layer would get thinner over time so that in the end, the
effective rating of the
capacitor was about what you had been running it at. This would seem to
imply that
purposely overrating a 'lyt is
Hello Thomas,
What you ask is possible, but only if the native crystal oscillator
frequency is close enough to the signal from the GPSDO. You
may have to tune the oscillator yourself to get it to lock, and you
may or may not find that the result is predictable from day to day.
This would depend
If you open it up, then simply connect a load resistor, perhaps
in the neighborhood of 100 ohms (but definitely not a direct short!)
across the super cap to drain it faster.
Dana
On Sat, Feb 23, 2019 at 8:00 AM Jason Rabel via time-nuts <
time-nuts@lists.febo.com> wrote:
> That page you linked
Keep in mind that the 7 min "warmup time" of the PRS-10 is jut the time for
the
unit to get the physics package close enough to final temperature for the
dithering
loop to lock to the atomic transition. But based on measurements of current
drawn
by the oven(s), it takes more like an hour for the
Folks,
Please be careful about definitions in this discussion.
To some people, "phase noise" refers to sideband noise, away from the
carrier, arising from some form of random phase modulation of the carrier.
To others, the same term refers to the underlying phase modulation itself.
While
I learned a useful rule of thumb design procedure for 2nd degree PLLs some
time ago
(I'll speak in the context of using an inverting op-amp in the loop
gain/filter stage):
Step 1: Short the capacitor in the opamp's FB loop, then set the resistor
so that
the PLL has the desired loop bandwidth.
My ancient T'bolt (purchased well-used several months ago) also went from
1023 to
1024. A quick look at IQ phase data I was recording (referred to a
free-running PRS-10)
shows no discernible glitch at the moment of rollover.
This old T'bolt has been living in 1999 for as long as I've had it. So
Well, I once had a nutty idea which was to detect earthquakes by looking
for the phase
variation of DTV station pilot carriers due to seismic waves propagating
around, thereby
changing the physical distance between transmitter and receiver in a cyclic
manner
until the 'quake calmed down. Doing
In answer to the question about radio astronomers, consider VLBI (Very Long
Baseline Interferometry).
VLBI is a mapping (imaging) process in which signals are *simultaneously*
received from
a small sky region of interest by a collection of radio telescopes
scattered about the world.
In order for
Chris,
In general I'd say that the rather high level sidebands on your
signal are not reasonable at all, but I think I see what's *really*
wrong: your SA settings. It looks to me like the tall signal
is the DC spur, (a.k.a. "start spur") of you analyzer, and
the signal very near center screen is
Ole,
Is it when all 5 conditions are met, or just any one of them?
Thanks,
Dana
On Wed, May 29, 2019 at 11:00 AM Ole Petter Rønningen
wrote:
> As supporting material; BIPM is considering when a redefinition would be
> appropriate:
>
Mark,
When you refer to "30 dBc", what is that? Is it the eb/n0 value? If so,
with the XLi's
behavior as you report it, your scheme would fail over most of the useful
signal range.
And, it will probably differ from setup to setup of the HW, depending on
all the parameters
that have already
One can reduce the gulp factor mentioned by Scott quite a bit by buying
one of the non-connectorized versions from Mini-Circuits and wiring up
one's own BNC connectors.
One thing to keep in mind with these isolating splitters is that the
isolation
between outputs is good only if the impedance of
Correction from Dana:
I meant "... without accumulation of phase error during normal times ...".
Sorry about that.
Dana
On Sun, Jun 23, 2019 at 11:45 AM Dana Whitlow wrote:
> Leo,
>
> Are you saying that you want to abandon phase lock altogether in favor of
> freq
&
Leo,
Are you saying that you want to abandon phase lock altogether in favor of
freq
lock? Or just during the reacquisition following loss of and restoration
of the
reference?
By me definition of pure freq lock, there will generally be some permanent
(but varying)
frequency error, so that phase
Glen,
This sounds like it might be one of those latent problems arising from the
GPS
week rollover that we've been warned about.
Dana
On Sat, May 18, 2019 at 4:00 PM Glenn Little WB4UIV <
glennmaill...@bellsouth.net> wrote:
> Did anything happen in the last 24 hours that would affect the time
Denny,
That is certainly a large difference. But I'm not clear on one point that
could
easily be very important:
Were the two antennas for the separate antenna test indoors, or on the roof?
If indoor, I kind of suspect that the difference might mostly be attributed
to the
change in antenna
Taka,
What happens to the timing of the PPS output and/or the phase of the 10 MHz
output during these wonky times?
This inquiring mind wants to know, as it is getting pretty close to
ordering a
PRS-10 for its own use.
Dana
On Thu, Apr 18, 2019 at 3:45 PM Taka Kamiya via time-nuts <
t subsystems could be isolated with
high-vacuum valves and switches, with the result that we kept the maser
operating
throughout the two procedures, with only a subtle glitch in timing accuracy
visible in the records when I checked after the fact. The observatory
continued
to operate with no disturbance
Perry,
The only H-maser with which I've had direct experience (the MHM-2010) costs
around $250,000 new. But there are some other brands, mostly foreign.
The immediate operating cost is that of AC power. IIRC, the '2010 uses
about
100W or maybe 125W, *all the time*. The H-maser is *not* the
I wonder if a case could be made for multi-GNSS reception in the case of a
poorly-
located GPS antenna at the reception site. That is, could the benefits of
having a lot
more sats in the sky outweigh poorer performance of some of the systems with
respect to other systems?
Dana
On Sat, Jul 13,
Sure sounds to me like the distribution amp does have some sort of shielding
problem, in effect.
Are the power connections (whether AC or DC) properly filtered? Are all
the
coax connectors' bodies well-bonded to the metallic enclosure?
You might want to try sniffing with a small diameter (~1
One what? I see that it is a Ublox unit, but see no reference to the
interesting
modern units like the 9 series. Also, I note that the only reference on
the board
to "ant" is on the lower right corner, while what I suppose to be the
actual antenna
connector appears to be an SMA near the upper
I'm surprised that the VF of HV transmission lines is noticeably less than
unity, given
that the dielectric is just air. Or does the distributed resistance do all
the damage?
Dana
On Mon, Jul 8, 2019 at 8:00 PM jimlux wrote:
> On 7/8/19 3:11 PM, Hal Murray wrote:
> >
> >
Chris,
Ok, one source is a PRS-10. Is it the DUT or the reference? And if it's
the DUT, what
is the reference source?
Dana
On Tue, Jul 2, 2019 at 8:00 PM Chris Burford
wrote:
> Hi Bob,
>
> I'm seeing 4.22E-12 as the slope value in the upper right of the TimeLab
> phase difference plot. Is
I've always noted that casual attempts to pick up 60 Hz with small antennas
etc see more harmonics and other trash than actual line frequency. But if
you're in an office environment, why not plug something in? It's quite easy
to build a simple passive diode clipper/filter that will plug into a
Steve,
I'm curious: in the absence of a PPS or other electrical output from your
"computer",
what is the nature of the time "output "? If it's just visual via a
display, why not view
the light output of the seconds digit with a photocell. Most of the
transitions should
produce an
Question:
Do you stabilize the oscillator inside the dewar, or do you stabilize the
temperature of
the dewar's outside environment?
This may boil down to a slightly different expression: Where do you *sense*
the temperature for
the stabilization loop? On the crystal itself, or on the outside
Thanks Forrest,
I've added this to my documentation packed for my own PRS-10; I suspect
that I'm
only a year or two from (possibly) needing it myself.
Dana
On Fri, Sep 13, 2019 at 3:00 AM Forrest Christian (List Account) <
li...@packetflux.com> wrote:
> Mainly wanting to post this to the list
I'd say that for the low price, the critical component (OCXO) can't be a
very good one.
It's too bad that the seller offers no real specifications (and that he/she
doesn't write
very good English).
I'll be "listening" with interest.
Dana
On Tue, Sep 10, 2019 at 7:32 AM Adam Kumiszcza wrote:
lue
for my interests. I'd dearly love to borrow one, as it would undoubtedly
provide
a good learning experience for me.
Dana
On Tue, Sep 17, 2019 at 3:11 AM Dr. David Kirkby <
drkir...@kirkbymicrowave.co.uk> wrote:
> On Tue, 17 Sep 2019 at 04:00, Dana Whitlow wrote:
>
> &g
Assuming that the T'bird works as you stated, you might still want to know
where in that
sawtooth the supposedly "fixed" error falls. Maybe this is unimportant if
all you want is a
stable reference frequency source, or very important if you actually want
to know what
time it is. However, the
It seems to me that the basic operation of the Rb cell and/or the filter
cell
and lamp must all involve the presence of some liquid Rb at normal
operating temperatures. Otherwise, temperature regulation would not
be a viable means of controlling the Rb concentration on the vapor mix.
If I'm
I can't speak for 1/2PPS, but at the Arecibo Observatory we distributed
1PPS with every
10th second's pulse stretched to about twice the duration of the others. I
did find that to
be kind of handy every now and then, when troubleshooting things.
Dana
On Sun, Sep 29, 2019 at 8:36 AM Gregory
It looks to me like one might be able to exploit a resonance of the
A-frame. Instead of
whacking it with a mallet, vibrate the tube in the appropriate direction at
the appropriate
frequency and run up the amplitude until (hopefully) the ribbon ends touch
on each
cycle as indicated by electrical
Somewhere, a few years ago, I saw a video in which a fairly large number of
metronomes
were mounted on a common base and exhibited some interesting injection
locking
behavior.
Personally I keep thinking of phase locking a G'father clock to a Rb
standard. The trick
will be to do so in a manner
Most modern GPS receivers are very quiet even barefoot. So, one could
argue that one should
not have much more LNA gain in the antenna than required to make up for
feedline loss, which
should be easily calculable. While excess gain in the antenna can improve
overall system noise
figure a small
Even without any funny business with boost converters (or whatever). those
copper wires
make a nice antenna for coupling noise from both ends (PC and USB
accessory) into
the environment inside the chamber. Unless, of course, the cable is
well-shielded, which
you did not mention.
I suppose it's
Hello Taka,
As long as you stick to CW sinewaves *and* the distribution amp specs are
honest when they say "buffered out puts", the problem is fairly simple. If
you're not seeing distortion under your operating load and signal
amplitudes,
it's OK and I'd not bother to change anything.
By
A friend of mine living in SE lower Michigan recently bought
a Geppetto GPS clock, and swears that it tends to lose
satellite lock on cloudy days but does OK on sunny days.
He is admittedly using a very poorly-sited antenna,
placed in a window because his house has aluminum
siding. He reports
If you're doing beam forming, the "one amp driving multiple
loads" approach is probably going to do the best and most
stable job of getting what you need. And all your loads should
be identical, not some mix of different makes/models.
But you will need to find an amplifier that can deliver the
Andy,
Isn't DirecTV downlinking around 12 GHz? Yet GPS L1 is at only ~1575
MHz. That's
a huge difference with regard to scattering losses, and probably a fair
amount of
difference for water absorption losses as well.
I've recommended that my old friend try putting his GPS antenna up in the
gt; https://ieeexplore.ieee.org/document/1337081
> ).
>
> Tim N3QE
>
> On Tue, Oct 22, 2019 at 2:01 AM Dana Whitlow
> wrote:
>
> > A friend of mine living in SE lower Michigan recently bought
> > a Geppetto GPS clock, and swears that it tends to lose
> > satelli
Corby, I have a question to add regarding the HP units: is the tip
temperature hot
enough to melt Rb in addition to providing vapor? If so, doesn't the
orientation of
the physics package in earth's gravity have to be about correct in order to
keep
the excess Rb in the tip?
Thanks,
Dana
On
My idea is that for the time this was built and used, there was little or
no need for really
accurate time keeping in most astronomy work. The high accuracy/precision
needs
really didn't arise until the beginning of what I'll call "modern
astronomy", which I'll loosely
define as the discovery of
Celestial navigation users might object to the notion that seconds are not
important.
That is, if you can find anybody still exercising that art. In that arena,
folks are
taught to read seconds first, then minutes, then hours.
Depending on the latitude, one second can lead to something like 1/4
You could minimize problems with accumulated differential delays by *not*
daisy chaining- rather arrange the splitters in a hierarchical fashion
so that all your outputs have an equal number of splitters in the path.
I think your problem is that you started with more than one GPSDO.
You need to
I once read that Supercapacitors come up short in handling really short
spikes,
and that this is not due to physical inductance arising from the
structure. Rather,
the issue was of a subtle (to me) electrochemical nature.
Can anyone either confirm or refute this? Inquiring minds want to know.
Bruce, is there any text about the ring resonator which discusses the
features in the
interferogram? Also I'd be interested in the configuration of the
electrodes.
My present interpretation is that the vibratory resonance stems from
contra-rotating
modes each propagating around the ring, and
Yes, oscillators that are harmonically related can indeed injection lock.
I've done it in
a project about 40 years ago.
In your case, you need to avoid RF cross-coupling between the oscillators.
This includes
both electromagnetic coupling, "direct coupling" via use of a common power
supply, and
If you start off viewing the crystal in series (S21) I believe that you'll
be able to see
some response far enough away from the resonance to make it easier to find.
Dana
On Thu, Feb 27, 2020 at 9:39 AM Magnus Danielson wrote:
> Hi,
>
> Even if my VNA steps in 1 Hz if I ask it kindly, it can
Matthias,
You said that the LPRO has a pulling range of 4 PPM. Really? I
would think that 4PPB would be much more likely for a Rb.
Dana
On Mon, Mar 2, 2020 at 3:21 PM Matthias Welwarsky
wrote:
> On Montag, 2. März 2020 18:32:44 CET Skip Withrow wrote:
> [...]
> > The Thunderbolt DAC steps
Probably the easiest solution would be to feed 1 PPS from the T'bolt into a
full-featured
PRS-10 Rb, then fiddle with the loop parameters in the PRS-10 to best suit
your needs.
Unfortunately, I'm told that most of the surplus PRS-10s have been stripped
of this capability.
But a new PRS-10 *does*
Perrier,
I see that several others have beat me to the punch on the digipot issues.
So I
think I'll sit this one out and just try to learn.
Dana
On Mon, Jan 27, 2020 at 7:50 AM Dana Whitlow wrote:
> Perrier,
>
> In answer to your 2nd question, I am unaware of any oscillator t
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