Don wrote:
the fet breakdown voltage has of course got to be high enough.
If the nuvistor is used as a common-cathode or common-grid amplifier,
you can cascode the fet with a bipolar to extend its drain voltage
range. You will need to come up with an appropriate bias source for
the
Thanks Charles:
I will consider your ideas as they seem to be excellent!
I wonder if I could just make the whole unit run off of +24VDC or +12
VDC.
I need to look at the schematics and see what would be the best way to
proceed.
I currently do not have an antenna for WWVB and need to get up and
Don,
what do you mean by not getting them sequentially? The stop signal should
determine the rate of the samples and if the stop signal is the test signal
then any non-uniformity in time is due to that signal. Maybe a good idea to
feed the stop trigger with the reference to assure the best time
You get an idea of the required changes when you look at the 10509A
antenna/preamplifier schematics in the 117A manual changes section.
There are both versions, nuvistor and FET covered. It's perhaps not as
trivial as one might wish.
Adrian
Ron Ward schrieb:
Thanks Charles:
I will consider
Schematics for all versions of the 10509A antenna:
http://www.leapsecond.com/museum/10509a/
/tvb (iPhone4)
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Hi Ron,
On 07/05/2012 07:12 AM, Ron Ward wrote:
Hi:
I am also new and would like information about ADEV, MDEV, HDEV, TDEV,
Phase and Frequency Difference.
You can start of with the Allan Deviation article on Wikipedia. It has
the focus on ADEV, from that the modified Allan Deviation is
On 07/05/2012 07:14 AM, Don Latham wrote:
So if the 5370 determines the data rate, then in calculating adev or
other such products, we're assuming the time differences are ergodic
because we're not getting them sequentially, but rather selecting the
delay intervals at long inetrvals between
On 07/05/2012 10:21 AM, Azelio Boriani wrote:
Don,
what do you mean by not getting them sequentially? The stop signal should
determine the rate of the samples and if the stop signal is the test signal
then any non-uniformity in time is due to that signal. Maybe a good idea to
feed the stop
Some time ago I made a 60 kHz antenna by winding a zillion turns of wire
on a ferrite loopstick tuned with a padder condenser. This connected to
the gate of a 2n4416 or mpf102. This was quite selective and sensitive.
On 07/05/2012 02:45 AM, Tom Van Baak (lab) wrote:
Schematics for all
Well, so I have to have stable values... but if I'm measuring my clock I
wouldn't expect stable values (of course at most, say, 1nS apart one to the
other for every second). That is, assuming that my counter samples at the
stop, have I to sample exactly at 1 second using the reference as the stop
Ron,
I would certainly be interested in any conversion scheme that you come up
with. I have 2 117's and hope to get them operational sooner rather than
later. -:)
Gordon WA4FJC
Date: Thu, 5 Jul 2012 00:14:32 -0700
From: Ron Ward
You do know that neither a 117A or a 207 will work when WWVB changes to
BPSK fairy soon?
-John
===
Thanks Charles:
I will consider your ideas as they seem to be excellent!
I wonder if I could just make the whole unit run off of +24VDC or +12
VDC.
I need to look at the
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I noticed the jamming begin at 0542 today 7-4-12.
It's precisely at 5 minute intervals and lasting 75 seconds each time
My loss of signal is 1 second after each 5 minute interval (using atomic PDT).
Signal returns 75 seconds later at 17 seconds after the next minute.
Date 7-5-12 los = loss of
I didn't see a message there. The closest jamming I could find follows:
ZLA LOS ANGELES (ARTCC)PALMDALE, CA. !GPS 07/006 (KZLA A1678/12) ZLA NAV GPS
IS UNRELIABLE AND MAY BE UNAVAILABLE WITHIN A RADIUS OF 400 NM AND CENTERED AT
393316N/1174400W OR THE LOCATION ALSO KNOWN AS THE MINA /MVA/ VOR
Yes. I would definitely be interested in information on your conversion.
Like you I would prefer attempting a successful conversion as I don't
have the knowledge to develop one myself.
Thanks,
Merchison
On 2012-07-05 3:14 AM, Ron Ward wrote:
Thanks Charles:
I will consider your ideas as they
NO! WOW! If this is true then you just saved me hours of work and lots
of for something that would end up being useless.
Will WWVB still be useable for frequency phase comparisons, perhaps by
long integrating periods?
I spent a lot of time and effort with LORAN and they just killed it.
As John has mentioned all of the old receivers are dead! They will not
lock to the new BPSK signal.
Though John and I have been working to see what can be done I have to
say to date lots of methods have been tried and none really all that
successful. These methods include phase lock,
Hi again:
Well I guess I will just use the Fluke 207 and HP117 for local standard
comparisons.
Ron
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of J. Forster
Sent: Thursday, July 05, 2012 6:31 AM
To: Discussion of precise time and
Yes they will still work well for that and the 207 does much better then
the 117 by about 10 X
Regards
Paul
On 7/5/2012 10:52 AM, Ron Ward wrote:
Hi again:
Well I guess I will just use the Fluke 207 and HP117 for local standard
comparisons.
Ron
-Original Message-
From:
Hi:
What is the new bandwidth for BPSK WWVB going to be?
Why are they going to BPSK, cheaper clocks?
How am I going to compare GPS to something to see if GPS is accurate?
What about 400.1 MHz GEOS?
Thanks,
Ron
-Original Message-
From: time-nuts-boun...@febo.com
Not sure why the email did not send
As John has mentioned all of the old receivers are dead! They will not
lock to the new BPSK signal.
Though John and I have been working to see what can be done I have to
say to date lots of methods have been tried and none really all that
successful. These
Many years ago I had one of these antennas that I used with a Gertsch
RLF-1 WWVB receiver. When the Nuvistors became old and feeble I
decided to change the 6CW4 Nuvistors to FETs. Being young and
foolish and thinking this is basically audio, I went to Radio Shack
and got some N-Channel FETs
It turns out my lacross projection, atomic, external temperature transmitter,
clock is the source of the jamming..
Apparently its trying to communicate with its external temp sensor which has
had a dead battery for months..
The projection clock is powered from ac mains and transmitts for long
Quite interesting the indoor unit that transmits hunting for the outdoor
sensor... usually the indoor unit receives only and the external sensor
transmits only. Your words imply that the LaCrosse clock/sensor is a
transceiver pair...
On Thu, Jul 5, 2012 at 5:21 PM, tom jones epoch_t...@yahoo.com
NO! WOW! If this is true then you just saved me hours of work and lots
of for something that would end up being useless.
It is true. It was discussed a few months ago. I have posted on the
testing repeatedly.
Will WWVB still be useable for frequency phase comparisons, perhaps by
long
Thanks for posting this and I'm glad you solved your problem. It's nice to see
actual examples of this type of interference.
--- On Thu, 7/5/12, tom jones epoch_t...@yahoo.com wrote:
From: tom jones epoch_t...@yahoo.com
Subject: [time-nuts] gps jamming source found
To: time-nuts@febo.com
I thought about doing that but I did not want to spend a lot of time
experimenting fruitlessly.
Thanks for the encouragement.
Merchison
On 2012-07-05 11:19 AM, Burt I. Weiner wrote:
Many years ago I had one of these antennas that I used with a Gertsch
RLF-1 WWVB receiver. When the
On 7/4/2012 11:09 PM, Charles P. Steinmetz wrote:
Don wrote:
the fet breakdown voltage has of course got to be high enough.
If the nuvistor is used as a common-cathode or common-grid amplifier,
you can cascode the fet with a bipolar to extend its drain voltage
range. You will need to come
Dear Group,
This thread just saved me from a prospective purchase of an HP 117.
Now the big question. Which instruments in general will be affected by
the BPSK transition? I have been reading about Kinemetrics 60DC WWVB
receiver and clock. It appeals to me if I find one. Will other WWVB
The only ones that will work are very recent designs.
The HP 117 and Fluke 207 will not work.
Many Spectracoms will not work. A few will. See their web site
The Stanford 620 will not, I believe. Some models may.
I posted a partial list some time ago.
Apparently, NIST is working on a receiver
Hi
Simple answer - they are still playing around with the signal format. It is
totally unclear what the final format will really look like. Until they make up
their minds there is only one safe bet - the clock on grandma's wall will still
handle the wwvb format they use. Anything more complex
The wireless data links in those R/C sensor type things don't operate
near GPS carriers, but their harmonics can land there. The
transmitted power allowed should be too small to interfere with
anyone's receiver farther away - yours is probably pretty close. I
believe that the remote senders do
Hi:
This is so frustrating!
Who makes cheap clocks? CHINA.
Who uses phase comparison? DOD, American Colleges and Universities,
Laboratories, Astronomers, American Private Industry, Time Nuts, ETC.
What is our government doing? They appear to be the best friend Chinese
manufacturers ever had!
Hi:
This is so frustrating!
Agreed.
Who makes cheap clocks? CHINA.
Who uses phase comparison? DOD, American Colleges and Universities,
Laboratories, Astronomers, American Private Industry, Time Nuts, ETC.
Not really. They have all drunk the GPS Kool-Aid.
To allow a second source for a
Hi
The real question is weather the BPSK will help us get significantly better
accuracy out of WWVB or not. If it does, time marches on. If not - total waste
of effort.
DSP based low frequency receivers are pretty easy to make. You still will need
those antennas and preamps to make them work
From what I've read, the mods are to improve the Time of Day, not the Time
Interval accuracy.
In my location (MA) WWVB was never as good as LORAN-C because of
propagation issues.
-John
===
Hi
The real question is weather the BPSK will help us get significantly
better accuracy
Hi
Propagation isn't going to change with modulation format, so that part will
still be with us. I'm wondering if some fancy processing on the new code might
have some advantages. It's not worth digging into until they have a final
format though.
Bob
On Jul 5, 2012, at 6:19 PM, J. Forster
On 7/5/2012 9:49 AM, Randy D. Hunt wrote:
On 7/4/2012 11:09 PM, Charles P. Steinmetz wrote:
Don wrote:
the fet breakdown voltage has of course got to be high enough.
If the nuvistor is used as a common-cathode or common-grid amplifier,
you can cascode the fet with a bipolar to extend its
Hi:
Yes, please make a .PDF File available!
Thanks,
Ron
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of bill
Sent: Thursday, July 05, 2012 3:57 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] HP
If propagation goes south, you loose track of the carrier phase, the basis
of the system. If your local standard is stable and close to right, that's
not a big deal. If not, you can easily go down the garden path.
-John
===
Hi
Propagation isn't going to change with modulation
A badly tuned/designed super-regenerative receiver can put out a lot of
garbage. For commercial products, the receiver needs FCC approval to
ensure this doesn't happen.
Mike
On 7/5/2012 4:03 PM, ed breya wrote:
The wireless data links in those R/C sensor type things don't operate
near GPS
WWVB is weak in the Oregon Rain Forest. Oregon Scientific
weather station consoles rarely get a good signal at my place.
Ditto for a Radio Shack alarm clock.
I did get workable reception back in the 70s using a PLL
circuit from a book. That was before CFLs and switching
power supplies.
Hi
And possibly if the bpsk does something useful, you can identify a carrier
phase slip and correct for it….
Bob
On Jul 5, 2012, at 7:19 PM, J. Forster wrote:
If propagation goes south, you loose track of the carrier phase, the basis
of the system. If your local standard is stable and
On 7/5/2012 3:57 PM, bill wrote:
On 7/5/2012 9:49 AM, Randy D. Hunt wrote:
On 7/4/2012 11:09 PM, Charles P. Steinmetz wrote:
Don wrote:
the fet breakdown voltage has of course got to be high enough.
If the nuvistor is used as a common-cathode or common-grid
amplifier, you can cascode the
I believe all electronics needs FCC approval for emissions. [Not my job,
but I know engineers that complain about compliance testing.]
433MHz is a freeband (ISM). Still, you are supposed to be clean.
On 7/5/2012 4:41 PM, Michael Blazer wrote:
A badly tuned/designed super-regenerative
I bought some low power 315 Mhz, 2400 bps transmitter and receiver modules to
use as a GPS data link. It turns out that the transmitter module can jam gps
within a half mile radius. Later, the maker of the modules disavowed all
knowledge of their existence
Does anyone know if there are any mods for these receivers for when WWVB
changes their modulation format?
Is the WWVB change a done deal? It makes no sense to me to change this
format as most people that carry a cell phone don't need a watch (nor wear
one) anymore, much less a WWVB enabled watch.
On Thu, Jul 05, 2012 at 04:19:25PM -0700, J. Forster wrote:
If propagation goes south, you loose track of the carrier phase, the basis
of the system. If your local standard is stable and close to right, that's
not a big deal. If not, you can easily go down the garden path.
If I read
Glad to know that it is not finalised as yet. When I read about this
wrinkle, I was about to put my units up for sale.
Merchison
On 2012-07-05 1:54 PM, Bob Camp wrote:
Hi
Simple answer - they are still playing around with the signal format. It is totally
unclear what the final format will
On 7/5/12 6:33 PM, gary wrote:
I believe all electronics needs FCC approval for emissions. [Not my job,
but I know engineers that complain about compliance testing.]
433MHz is a freeband (ISM). Still, you are supposed to be clean.
433 is NOT an ISM band in the US (or in region 2, for that
Paul Swed and I have been working on this for a few months, mostly using a
standard method of extracting the carrier from a BPSK signal by analog
squaring it to make 120 kHz, then dividing that by two.
The problem is, with the poor signal on the east coast, the divider,
whether a flip-flop or a
On Thu, Jul 05, 2012 at 04:19:25PM -0700, J. Forster wrote:
If propagation goes south, you loose track of the carrier phase, the
basis
of the system. If your local standard is stable and close to right,
that's
not a big deal. If not, you can easily go down the garden path.
If I read
On Thu, Jul 05, 2012 at 11:13:32PM -0400, Merchison Burke wrote:
Glad to know that it is not finalised as yet. When I read about this
wrinkle, I was about to put my units up for sale.
Put them up for sale. If you can find a buyer.
I asked Mr. Lowe this week and was told
No residual carrier is required.
-John
On Thu, Jul 05, 2012 at 11:13:32PM -0400, Merchison Burke wrote:
Glad to know that it is not finalised as yet. When I read about this
wrinkle, I was about to put my units up for sale.
Put them up for sale. If you can find a
Hi Ed,
It's not just just cheap and nasy regens that cause this problem. Some
aircraft navigation and communication receivers where found to have enough
local oscillator harmonic leakage at 1575 MHz through the antenna port to jam
GPS then tuned to specific frequences. The cure was a tuned
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