Nick,
altough you have been asking for advice for the VCO I would like to draw
your attention on how you can improve your phase detector. Edge-triggered
phase detectors are not bad, the even can work as frequency detectors if you
are far from lock and help you to gain lock where a XOR would not. H
Scott Burris wrote:
Does anyone know if there are any > 5min recordings of WWV audio available?
http://www.youtube.com/watch?v=9CpsPgXyIm8
--
Linux 2.6.30
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/
Hi
A good 64 MHz VCXO should have *better* phase noise at 100 Hz than the
multiplied 10 MHz out of a GPSDO. Even if you don't hit "state of the art" at
100 Hz, it will be better past a few hundred Hz.
A narrow loop is just fine.
If the bandwidth gets to wide, you have to start worrying about
>You can even build an injection locked divide by 5 stage.
>Choosing the right oscillator topology and injection method allows high
>level injection to be used with an LC oscillator.
>
>Bruce
>
Are there references to some practical circuits? That would be great.
A google search on "injection lo
Thanks Stan,
That worked, I did not see the control menu properly!
I set the co-ords to 0 0 0 and started survey. The Tbolt found the Lat long
withing a few minutes and only the altitude is about 70 M below the official
figure for my place. I live a a few hundred meters from Bangalore center a
Raj,
Ask them about ellipsoidal and orthometric heights, or the local
difference between the geoid and the WGS84 ellipsoid. Also your long
and lat may change depending of the Geodetic Reference System chosen.
By default GPS receivers use WGS84 and ellipsoidal height.
73 de Ignacio, EB4APL
Try to find your correct height here:
http://sps.unavco.org/geoid/
If you put in your correct coordinates without any input for the elevation,
you will get theorthometric height, which is the GPS ellipsoidal height
minus geoid height. That is the amount you need to subtract from
your Thunderbol
John,
Thanks for the reply.
I don't know the history, just got it. When first plugged in, Photo I and
2nd Harmonic go full scale then promptly come back to 0 (center). Supply
indicates normally, Lamp Oven, Cell Oven and Osc Oven all go full scale and
stay. After about 20 to 30 minutes, they com
Thanks for all the pointers.
I've come to a new intense dislike of electrolytic capacitors while debugging my
clock. One was really bad in the radio receiver board's AGC circuit, causing
oscillation,
so I ended up recaping every electrolytic I could find. Probably not too
surprising in
a 20+ y
Hello Arnold,
Thanks for that pointer, the height calculator works out nicely.
for my location I estimated height above mean sea level as
235' (ground level) + 10' (height of the tripod and mast to the GPS puck
antenna)
or an estimate of 245' ASL.
The calculator shows:
Your Input Coordinates
Hi
That's the problem.
There's no debate that you can injection lock oscillators. The problem is that
the analytic side of designing an injection lock system is a bit lacking.
With a PLL there's an over abundance of information on how to do the design,
how to analyze it, and how to test it.
Bob Camp wrote:
> That's the problem.
There's no debate that you can injection lock oscillators. The problem is that the analytic side of designing an injection lock system is a bit lacking.
Rohde has in [1] a deluge of math on mutually coupled resonators and
oscillators,
including noise an
Hello Raj,You should leave the tbolt coordinates set to the WGS84 coordinates
that the receiver determines and not what a surveyor might come up with (which
will probably be in some coordinate system offset from WGS84).Also the latest
version of the Lady Heather beta program just uploaded to Jo
Joop,
you may also search for "synchronous oscillator". You will find for example:
http://www.amalgamate2000.com/radio-hobbies/radio/synchronous_oscillator.htm
Best regards
Ulrich
> -Ursprungliche Nachricht-
> Von: time-nuts-boun...@febo.com
> [mailto:time-nuts-boun...@febo.com] Im Auf
BOB,
It was one of the "special" custom built units by HP not listed in the
catalogs.
Corby
Weight Loss Program
Best Weight Loss Program - Click Here!
http://thirdpartyoffers.juno.com/TGL2141/c?cp=kMEWeb94FL0JuWMG2jQkggAAJ1ABLZFyqoH-WnH
Bruce wrote.
A full wave rectified sinewave has only even harmonics present.
True, but it needs a center tapped coil.
Regards.
Max. K 4 O D S.
Email: m...@maxsmusicplace.com
Transistor site http://www.funwithtransistors.net
Vacuum tube site: http://www.funwithtubes.net
Music site: http://
Hi Ulrich and all, you kicked up an old memory. In the early 1960's a
friend and I messed some with nuclear magnetic resonance and synchronous
oscillators for detection of same. Later found a nice paper:
Uzunoglu and White, IEEE Journal of Solid-State Circuits V. SC-20,#6,
Dec.1985, p.1214-1226. Ha
True, photo current should still be present if you have cell flooding. Only
the second harmonic would be affected by that. Amplitude should be stable
immediately after power-up, so my guess is there's a supply regulation
problem. Check the supply voltage to the OCXO, and if OK, check the output
Yes, I wrote I searched for that too. This indeed is one circuit I found.
At first glance the biasing does not give me the impression it might be a
very good oscillator by itself. But then again, that might be a requirement
in order to allow it to lock to another signal.
James G1PVZ wanted to see
That's a great suggestion, Ulrich. Thanks. It took all of five minutes to
implement in VHDL, and looks great.
I also found Fox's "Xpresso" line of miniature synthesized VCXOs, and the
numbers look pretty compelling. CMOS output, too. And, the best part, they're
available off-the-shelf. Does an
Hi all,
I have a CTS Knights TCXO, P/N 970-3832-0. Frequency is 10 MHz.
Anyone knows the working voltage? Date code is from 1987, too old for
Internet :-)
73 - Marco IK1ODO
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to http
Not if one uses a balun.
Bruce
Max Robinson wrote:
Bruce wrote.
A full wave rectified sinewave has only even harmonics present.
True, but it needs a center tapped coil.
Regards.
Max. K 4 O D S.
___
time-nuts mailing list -- time-nuts@febo.c
If there are any Nuts out there interested in helping to make available to
other Freq-Nuts a SIMPLE tester that I have found to be a VERY useful low
cost tool, contact me off line.
warrensjmail-...@yahoo.com
The tool is based on an OLD but seldom used method called the "Tight
Phase-Lock Loo
Marco,
My Stanford Research FS700 Loran receiver from about that time period has a
CTS Knights 970-2097-0 10 MHz ovenized oscillator in it, and it ran from +
and - 15 Vdc. I don't know if this is of any help at all.
73,
geo - n4ua
On Wed, Feb 10, 2010 at 4:09 PM, Marco IK1ODO wrote:
> Hi all,
Hi
In general the synthesized parts are not real low noise. You can do better
with $5 worth of parts and some tinkering time.
Bob
--
From: "Nick Foster"
Sent: Wednesday, February 10, 2010 4:08 PM
To:
Subject: Re: [time-nuts] Low phase noise V
> -Original Message-
> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
> Behalf Of Marco IK1ODO
> Sent: Wednesday, February 10, 2010 1:09 PM
> To: Discussion of precise time and frequency measurement
> Subject: [time-nuts] CTS TCXO
>
> Hi all,
>
> I have a CTS K
cool. I found Xilinx CPLD's mounted up on through-hole boards for $18.00
at Digilent. I have other Digilent products and they're good...
Don
Nick Foster
>
> That's a great suggestion, Ulrich. Thanks. It took all of five minutes to
> implement in VHDL, and looks great.
>
> I also found Fox's "Xpres
A while back there was a discussion on just how Trimble's AMU (amplitude
measurement units) signal levels related to the dBc values. Here is a
conversion table.
It was generated by doing a 24 hour antenna signal level survey in dBc and
another one in AMUs and then comparing the resulting val
My experience is that CTS are very helpful in providing info on old products.
73,
ian
> Date: Wed, 10 Feb 2010 22:09:05 +0100
> From: Marco IK1ODO
> Subject: [time-nuts] CTS TCXO
> To: Discussion of precise time and frequency measurement
>
> Message-ID:
> Content-Type: text/plain; char
It is essential to understand exactly how this system works in theory.
No amount of hand waving or protestations will make its problems go away
if you use inappropriate signal processing methods.
The tight PLL (or any other PLL) forces the VCO (VCOXO int this case) to
servo the fluctuations in
Hello Geo,
Do you know where I can get a replacement 10 MHz VCXO to replace the one
in my FS700 ?
I would prefer a drop in replacement like the CTS Knights.
Stan, W1LE Cape Cod
George Dubovsky wrote:
Marco,
My Stanford Research FS700 Loran receiver from about that time period has a
Hello The Net:
About a year ago I asked CTS Knights that very question.
They said it was a custom unit and they would NOT divulge the specs.
They referred me to SRS, their customer.
So I talked with SRS and they would only sell me a complete FS700
rebuild service
for more money than I wanted t
Bruce Griffiths wrote:
Not if one uses a balun.
or a 4 diode bridge rectifier :-)
(but more loss)
Gerhard
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the i
Hi,
As others have already noted, there's a paucity of circuits or down to
earth advice on this topic - unless your poison is "millimetre wave"
technology.
I set out to GPS-lock my Icom 706 transceiver some while ago. This uses
a (single) hi-stability master 30MHz xtal oscillator. With support
> -Original Message-
> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
> Behalf Of Kit Scally
> Sent: Wednesday, February 10, 2010 3:55 PM
> To: time-nuts@febo.com
> Cc: Kit Scally
> Subject: [time-nuts] Injection locking
>
> Hi,
>
>
> As others have already not
You might want to look for
R. Adler, "A study of Locking Behavior in Oscillators"< Proc of IEEE, v 61,
pp1380-1385, Oct 1973
Or
K. Kurokawa "Injection Locking of Microwave Solid State Oscillators", same
issue, pp1386-1410.
Those seem to be papers that get cited a lot.
The coupled oscillator pha
My GPS reading is about 850 +- 1
The "official" height ASL = 920
This calculator gives me ~936
So what should I use ?
Thanks
Raj
At 10-02-10, you wrote:
>Try to find your correct height here:
>http://sps.unavco.org/geoid/
>
>If you put in your correct coordinates without any input for the eleva
Raj,
Use the GPS reading, at least it has to be consistent with itself...
Ignacio
Raj wrote:
My GPS reading is about 850 +- 1
The "official" height ASL = 920
This calculator gives me ~936
So what should I use ?
Thanks
Raj
___
Hello everyone,
I am new to this list, happened across it while searching on distribution
amplifiers.
I need to design a 10 MHz isolation/distribution amplifier with two outputs for
a high-vibration wide temperature range environment. I was considering using a
design based on the NIST article
Raj wrote:
My GPS reading is about 850 +- 1
The "official" height ASL = 920
This calculator gives me ~936
So what should I use ?
Use the self-survey result. The GPS isn't wrong, it's just reporting
your altitude in a different system than you are used to. The
calculator allows you to check
life speed wrote:
Hello everyone,
I am new to this list, happened across it while searching on distribution
amplifiers.
I need to design a 10 MHz isolation/distribution amplifier with two outputs for
a high-vibration wide temperature range environment. I was considering using a
design based
Here is a new and improved AMU to dBc conversion file. It smoothes out a bump
in the data around 3-6 AMU. This file is also formatted comma delimited for
easier import into spreadsheets. You may need to delete the first (header)
line.
Ignatio and Charles,
Thanks. Makes sense to me now. I am interested only in the 10MHz frequency
generated and I suppose that it may not be affected by slight mismatch.
Raj
>Raj,
>Use the GPS reading, at least it has to be consistent with itself...
>
>Ignacio
At 11-02-10, you wrote:
>Raj wrot
Hi
How quiet does in need to be (phase noise)?
How clean does it need to be (harmonics)?
How much isolation / how much gain do you need?
How well do the outputs need to be matched / do you need a broad band match?
Does the issue with transformers also extend to other inductors?
Is cost / mil
Avoiding transformers and inductors will make it virtually impossible to
achieve very low phase noise as the dc gain from say the base of any
transistor in the chain to the output will degrade the flicker phase
noise. Using transformers or using an inductor to shunt any collector
resistors redu
Hi
Is your OCXO vibration isolated?
If not and it's got "typical" g sensitivity, your phase noise in an aircraft
may be much worse than the static numbers.
If you are sending the signal a distance to your systems, a balanced feed
may be the only way you will deliver a clean signal at the far
Clay
You could try something like the attached circuit schematic.
Austron used buffer amplifiers like this albeit without the
complementary symmetry output stage.
There are no transformers and the dc gain is low.
Simulated reverse isolation at 10MHz is around 120dB.
Simulated crosstalk between
Clay
Circuit schematic for one of the JPL isolation amplifiers is attached.
Unfortunately (apart from the few I and others may have) these
transistors are difficult to obtain.
However modern equivalents could be substituted.
Bruce
life speed wrote:
Avoiding transformers and inductors will ma
Attn: John Ackermann
Not sure what happened to produce 2 identical posts but as far as I can
tell I only posted this once.
Bruce
Bruce Griffiths wrote:
Clay
Circuit schematic for a more recent JPL isolation amplifier design is
attached.
Bruce
John
As far as I can tell only one copy of one of my recent messages was
added to the time nuts archives.
However 2 copies appear to have been sent to those on the list.
My machine indicates that only one copy was posted to the list.
Bruce
___
tim
fyi. -ch.
Symmetricom Announces Commercial Time-Scale System
February 10, 2010
http://www.gpsworld.com/wireless/timing/news/symmetricom-announces-commercial-time-scale-system-9518
Symmetricom, Inc., a supplier of preci
Charles, Raj,
> Raj wrote:
>
>>My GPS reading is about 850 +- 1
>>The "official" height ASL = 920
>>This calculator gives me ~936
>>So what should I use ?
>
> Use the self-survey result. The GPS isn't wrong, it's just reporting
> your altitude in a different system than you are used to. The
> ca
If there are any Nuts out there interested in helping to make available to
other Freq-Nuts a SIMPLE tester that I have found to be a VERY useful low
cost tool,
Warren,
Yes, I think it's a good idea for a couple of people to try to
duplicate your results; either to validate the resolution and
f
53 matches
Mail list logo
