On Nov 25, 2011, at 2:36 PM, Ziggy wrote:
> While in Florida on business last week, fairly close to Cape Canaveral, I
> stopped in at the only surplus house I could find: AstroToo in Melbourne.
Paul;
When next you are in the area, check out Skycraft surplus in Orlando.
http://www.skycraftsurpl
On Nov 7, 2011, at 11:30 AM, Jim Lux wrote:
> On 11/7/11 7:21 AM, paul swed wrote:
>> Wow for the rich and famous I see. $259 is about what a whole laptop costs.
>> :-)
>>
> Yes, but then you still need to write the software for that laptop.
>
>
> Think of it this way.. you're a non-software-d
Perhaps take advantage of one of the numerous AM radio stations in the midwest
that happen to be about half way between?
After some initial calibration that should be repeatable.
Tom Frank
On Oct 24, 2011, at 2:12 PM, paul swed wrote:
> Boy I have to say that I agree with Bob. Nice and simple
>> BLOCK: This may be kind of an urban legend, but I thought I had heard that
>> one of the backers behind extending Daylight Saving Time into the beginning
>> of November was the candy industry, and it all had to do with Halloween.
>>
>> Mr. DOWNING: This is no kind of legend. This is the truth
On Jul 2, 2011, at 5:35 AM, WB6BNQ wrote:
> To all,
>
> Here is just the right kind of TIMER to have. Quite an interesting
> effort that
> went into this project.
>
> http://www.evilmadscientist.com/article.php/555stool
>
> BillWB6BNQ
Memo to metrology lab: you were supposed to stop us
They ARE a lot cheaper than actually building more power plants.
What with all the government permits and lawsuits that takes time, money,
effort.
A "Smart" grid is much simpler, and can make them just as much money.
Tom Frank
On Jun 27, 2011, at 5:49 PM, J. Forster wrote:
> IMO, smart meters
On Jun 25, 2011, at 7:31 PM, Jim Lux wrote:
> although it's a lot easier if one of the links is down and they're running
> with the ocean return path.
Ocean return path? Please say more.
I picture a gigantic carbon electrode stuck in the ocean by a power station -
rather like the core of a
Fascinating.
1. Does anyone know if they have different models for 50 and 60 Hz regions (or
is the internal software smart enough to differentiate)?
2. Any else think this is a questionable approach for a watch that is heavily
advertised (at least around here) as being great for the boating set
Stan;
Here is a source for the necessary tools:
http://www.ofrei.com/page557.html
Note that they are not inexpensive; something to factor in when you consider
the overall cost of maintenance.
If it really has been 20 years, there is every possibility that the battery has
leaked, in which case
On Dec 24, 2010, at 12:00 PM, Michael Poulos wrote:
> We all enjoy good accurate time keeping. :) What is your favorite watch? My
> watch (so far) is a Casio WaveCeptor digital watch that gets the WWVB signal
> and calibrates itself that I bought for $50 at a WalMart - the price of one
> Chica
> I await the day when someone opines as to the number of angels that can
> dance on the head of a GPS antenna.
Oh dear, now I have this vision in my head of a bunch of angels impaled upon
the antennas of a GPS satellite, much like how some of the folks who get
involved in the "Running of the Bu
Sites communicate via landline telco. If there are sufficient mutually
visible networked sites to form a solution on an aircraft visible to
stations not in the timing network that would work, and is one of the
options we are studying.
May it be assumed that the sites are on the regular electric
On Sep 5, 2010, at 8:01 AM, Steve Rooke wrote:
Meant to add, my Z3805 always used to report that the antenna hight
was +7.50m (MSL) but now it is saying +6.20 (MSL), if you believe
that.
Steve
That might be something worth investigating.
After all, if it's true, that's not a good trend...
I would suggest you buy an old surveying transit.
This is what largely they were intended for.
With the industry going electronic, really nice ones can be found
fairly inexpensively (considering the quality of the optics on the
good ones).
I picked up a nice K+E with the tripod for $300.
On Jul 16, 2010, at 4:08 AM, Peter Monta wrote:
Rex wrote:
I just eyeballed the minute turn-over but it was clearly within
about a second.
Well, apparently it is a phone issue and not a cell-tower issue.
Searching the support forums yields the following trick: disable
the automatic time s
FWIW, my iphone is presently 15 seconds slow wrt Emerald (which
matches my GPS based clock as closely as my eye can judge).
Tom Frank, KA2CDK
On Jul 15, 2010, at 10:40 AM, Mark Gulbrandsen wrote:
Now if only Apple would allow Emerald Time to correct the i-
phone's internal clock we'd actual
Jul 4, 2010, at 11:36 PM, Thomas A. Frank wrote:
I'd like to make the same request.
Thanks!
Tom Frank, KA2CDK
On Jul 4, 2010, at 7:55 PM, James Robbins wrote:
Is there anyone here in the US who can offer the 16f688 chips for
sale and/or provide programming for the chips? All associated
I'd like to make the same request.
Thanks!
Tom Frank, KA2CDK
On Jul 4, 2010, at 7:55 PM, James Robbins wrote:
Is there anyone here in the US who can offer the 16f688 chips for
sale and/or provide programming for the chips? All associated
costs would be paid, of course. Many thanks.
Jim
Doesn't that mean that we're 'due' for some great propagation again?
If so, how will that affect our reception of WWV and WWVB?
Perhaps we will be entering a time of great time keeping with
multiple sources for precise signals...
Tom Frank, KA2CDK
On Apr 20, 2010, at 4:47 PM, Bill S wrote:
On Apr 10, 2010, at 2:29 PM, Bill Hawkins wrote:
Tom, I don't intend to challenge your knowledge but to discuss
the subject. It's amazing what a different viewpoint can do, and
how difficult it is to share viewpoints in email.
No worries.
As a person who grew up with synchronous clocks, whe
ve to generate (at 60 Hz) 60 * 3600 * 24 cycles per
day to keep the synchronous clocks happy. Ah, +/- 60 for a leap
second.
Bill Hawkins
-----Original Message-
From: Thomas A. Frank
Sent: Friday, April 09, 2010 11:52 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [
On Apr 10, 2010, at 11:31 AM, Eric Garner wrote:
My question is why is it done that way at all? It seems impractical
in the extreme. Why not use a meter? Or the afore mentioned
vibrating reeds?
What happens when the clock rates sync up again, since the wall
clock time will still be ahead
In this case, the reference clock appears to refer to GPS satellite
time,
but
uses a standard wall clock to display it. It is the reference clock
that
slowed down when it should have failed to work at all. Perhaps the
wall
clock
(maybe it was really a HP 113) needed oil. There's the real
Folks;
In as much as most of us can only afford this hobby if we buy
surplus, I was wondering if you folks would care to share some of
your favorite surplus places?
My specific "need" involves a trip to Birmingham AL and Atlanta GA
two weeks hence. Can anyone recommend any worthwhile pla
I don't believe that there is a 1pps available to the OS.
The GPS chipset seems to provide a very limited amount of data to the
phone. For example, there does not appear to be any way to get
satellite status info from the GPS chip to the OS. At least none of
the apps I've tried thus far (
I'm curious to know a little more about what was used to measure
the LED spectra. Not familiar with a "diode spectrometer" and
Google is not being very helpful. The last time I measured optical
spectra was a long long time ago using a PE UV/Visible
spectrophotometer in the early days of s
The largest discharge we got was from an acrylic rod and the cat.
Speaking of cats...one of mine has learned that he can rub across the
blanket on the bed and build up quite a charge.
In the middle of the night, if one of the other cats is in 'his
spot', it is not uncommon to find him rubb
Even cheaper and less work than plywood - solid wood doors from Home
Depot, laid across a rectangle using 2x4 as horizontals with 4x4 as
legs.
It you use lag bolts (and you should, as nails work loose over time),
you can take the things apart when you move.
My buddy has a few that all his
I picked up a very nice 0-4kV 0-200 ma adjustable lab supply on eBay
for $100 (delivered...and it weighs 50 pounds) last month.
It has voltage, current, or (uniquely) power limiting available.
The search term to add is electrophoresis. Apparently the medical
community does some interesting
Rather like the Shortt clock, only magnetically coupled.
Nifty idea.
Tom Frank, KA2CDK
On Jan 9, 2010, at 3:36 PM, Bob Camp wrote:
Hi
How about a rotary pendulum on a quartz fiber spring with some kind
of trick magnets to drive it / read it out? Put the pendulum and
spring inside an ev
On Dec 26, 2009, at 10:36 AM, Robert Lutwak wrote:
I pay pretty close attention to what people in this field are
saying, and I've never heard anyone say "we'll get to 1e-11 short
term stability at 1 second real soon now."
1e-11 at 1 second is the XPRO spec (and 2X better than LPRO or
PRS
I have read that there have been studies with a spectrum
analyzer system on planes that have shown that compliance with the no
radiating device rules and electronics off during takeoff and
landing is
far less than 100% though I certainly would not personally
deliberately
violate the l
saying angrily "using a GPS on a
plane is illegal".
Nonsense...unless their own rules prohibit such use, in which case
you are legally obliged to comply. There is no blanket (ie:
government) rule against them.
It is up to the airline; in the past year I've flown a number of
different
Folks;
Writing as someone in the US, I keep seeing interesting available
electronic components coming out of Russia, the Ukraine, etc. on
eBay. I rather suspect there are a lot more types available than what
I see there.
Can anyone recommend any web sites where there might be spec sheets,
On Jul 24, 2009, at 3:18 PM, Tom Van Baak wrote:
Typical TAPR Thunderbolt phase noise is about -100 dBc/Hz
at 1 Hz, falling to about -150 at 100 Hz, with a floor just above
-160 beyond 10 kHz. Variations on this, and spurs, seem to be
a function mostly of power supply. For example, see:
http://
I just don't know what to say to that! Even a child can put a
case of bottled water in a box, and not have it evaporate or leak.
I would venture that said case of bottled water will still be full
up when the child graduates from college, and has kids of his own.
But goodness knows what sort of
Time to shrink the atomic clock
14 March 2009 by Anil Ananthaswamy
Magazine issue 2699. Subscribe and get 4 free issues.
ATOMIC clocks, currently the size of fridges, could shrink to the
microscale thanks to a new way of measuring the second. The technique
could also see aluminium displace cae
http://www.engadget.com/2009/02/13/this-afternoon-party-like-
its-1234567890-unix-time/
This afternoon, party like it's 1234567890 Unix time
by Ross Miller, posted Feb 13th 2009 at 5:41AM
Number aficionados, you probably already know what happens today. As
of 6:31:30PM ET this afternoon it wi
>> For me, PST, UTC midnight is 4 PM, a convenient time to watch.
>
> For those of us in the zulu time zone (near the Greenwich
> meridian), happening
> just as the new year is about to start is not *nearly* so
> convenient - especially
> if you are trying to transmit new year celebration progr
On Dec 20, 2008, at 6:03 PM, Burt I. Weiner wrote:
> I suppose a good comparison would be: How accurate does the
> speedometer in the car really need to be and why.
Accurate enough so that if its reading matches the posted sign, you
don't receive a ticket?
Tom Frank, KA2CDK
Since we're telling horror stories...
Circa 1990, I had a really nice strip chart recorder in a half height
roll-around rack. Shipped it to the field for some work, everything
was fine. Shipped it back; it made it all the way to our facilities
heavy freight guys in perfect condition. It w
>> I would say it's very unlikely to happen. People tend to prefer the
>> time in their area to match up with the day. So, having the sun
>> come up
>> at 7pm wouldn't suit a lot of people.
>
> But people would get used to it after a while, maybe a generation, and
> whose to say that the sun sh
>Welcome Greg;
>Everybody has to jump in someplace. Some of us just jump in a
little deeper.
A few drown...
(nice podcast, by the way)
Tom Frank, KA2CDK
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com
Hi Carl;
I am.
Tom Frank, KA2CDK
On Oct 24, 2008, at 9:57 AM, Carl Dreher wrote:
> Hi,
>
> Just wondered how many people on this list are also members of the
> Horological Sciences chapter of the NAWCC?
>
> Carl Dreher
>
___
time-nuts mailing list --
> A ceramic alignment tool doesn't cause the same behaviour, but a
> probe sure
> does.
Something is whispering "grounding".
I'm not sure why, but that is where I would start looking...
Tom Frank, KA2CDK
___
time-nuts mailing list -- time-nuts@fe
> Trivia: The engineer who designed that chip for HP 35 years ago
> has the cubicle next to me at Agilent Labs! It was considered
> very advanced at the time.
> --
> The cubicle?
> -
> Think of it as many nested boxes, within the building there is a
> room, within the room
Jim;
Congratulations, that is a really nice looking clock!
You may have a real gem there. While the movement doesn't look like
anything special, the pendulum looks like a Riefler.
Which is something quite special...sort of like having a Thunderbolt
inside your bedside alarm clock...
Tom Fr
> tvb indicated that the unit builds were from ~2005, and indeed, the
> photo of the TAPR package on Leapsecond.com shows a TBolt from 2005
> revision 'E'. The unit I received is build 2002 revision 'B'.
> Anyone know of differences in the revisions, and whether the OCXO
> (which Tom found
>>> It turns out every one of these units stopped working sometime
>>> Sunday and
>>> they don't fully understand the cause or the fix as of yet. Good
>>> news, I
>>> don't have a malfunctioning unit.
>>
>> Funny, but to me, having the thing stop working qualifies as
>> "malfunctioning".
>>
>> Jus
> It turns out every one of these units stopped working sometime
> Sunday and
> they don't fully understand the cause or the fix as of yet. Good
> news, I
> don't have a malfunctioning unit.
Funny, but to me, having the thing stop working qualifies as
"malfunctioning".
Just a thought.
Tom
> The thought was that there as interference arcing or corona noise
> from the
> line insulators, and a receiver (AM) was deployed to listen for
> what was
> expected to be a substantial wide band noise signalwe didnt
> hear one! We
> are now confused about what the effect is. The signal
> Only the clockwork and the coils. All the clocks will be wired
> in parallel.
Traditionally, such systems had all the slave coils in series.
I suspect you will find that the better way; less room for weirdness.
Otherwise, I like it!
Tom Frank
__
> The way to make a HP10811 immune to humidity is to seal it in a metal
> container with glass leadthrough seals
> after it has been flushed with dry nitrogen for a few days.
Or perhaps pump it down to a vacuum, hold for a couple of hours, then
fill with dry nitrogen?
Just don't power it during
On Jul 16, 2008, at 10:46 PM, Didier Juges wrote:
> One issue with the Noritake display (common to all VFD devices) is
> that it
> draws over 100mA of current at 5V. A 3 terminal linear regulator
> running
> from 12V will need a reasonable heat sink to operate. A better
> choice would
> be a
On Jul 3, 2008, at 7:16 PM, Carl Walker wrote:
> On Fri, 2008-07-04 at 01:02 +0200, Magnus Danielson wrote:
>>> The analog side would need to allow for those signals also then.
>>
>> Naturally. The antenna-amplifier design will need to be more wideband
>> oriented. Should not be too hard thought.
Thank you for the information, which I find rather disappointing.
For some reason, I had an expectation that a GPS would find its own
position and save it, perhaps with a manual click, rather than having
the operator write down the values and have to type them into some
data entry boxes on a
> I've another antenna, but is a cheap one with
> magnetic base, only used for a nixie clock :)
I have one of those as well, a Trimble 28367-40 from eBay, it is
feeding my Thunderbolt (thank you TVB!), and it works fine just
sitting on the window sill - inside!
I am curious, however...how do
<>
Switzerland's obsession with time
Switzerland is famous for its watches and its trains that run on
time. But, asks Imogen Foulkes, can punctuality become too much of a
good thing?
In the centre of Bern there is an electronic clock which is ticking
off the days, hours, minutes and secon
Hi;
I bought a number of these for work and we've been very pleased with
them:
The GP1305TP version. One fixed +5, and two variable (but they can
be locked for eg: +/- 15) outputs.
> http://www.testequipmentdepot.com/ezdigital/gp1305.htm
Tom Frank, KA2CDK
___
That brings back memories...
When I was in high school (1970's), I was a member of an Explorer
Post (related to Boy Scouts) that specialized in electrical engineering.
The host was the AT+T facility that manufactured the repeaters for
their undersea cables (now owned by Tyco I think).
One of
I suggest you follow the link at the bottom, because the original
page has a nifty video embedded in it.
Enjoy!
Tom Frank
--<>
Atomic rhythms give precise fix
By Jonathan Fildes
Science and technology reporter, BBC News
Please turn on JavaScript. Media re
>> I checked my Tom-Tom One XL today, and #32 showed up on the satellite
>> screen, although it's signal strength bar was "grayed out", even
>> though the signal strength was higher than most of the other
>> satellites.
>>
>> I'm guessing that this means the GPS was seeing #32 as unhealthy, or
>>
Hello All;
I checked my Tom-Tom One XL today, and #32 showed up on the satellite
screen, although it's signal strength bar was "grayed out", even
though the signal strength was higher than most of the other satellites.
I'm guessing that this means the GPS was seeing #32 as unhealthy, or
was
A more in depth book on Harrison and the longitude problem is:
"The Quest for Longitude", Proceedings of the Longitude Symposium
Harvard University, Cambridge Massachusetts
November 4-6 1993
edited by William J. H. Andrewes
Harvard University, 1996
Sobel attended the above symposium, which is whe
> The best experiment I can think of to prove this is to run the
> oscillator in a paper bag until it is stable,
> then trickle a flow of dry nitrogen into the bag for a day or two
> and watch for oscillator drift as the humidity
> in the oven drops to extremely low values.
> It is a pity that I d
> The results are better than new. I even enlarge the text and numbers
> slightly for my aging eyes!
>
That sounds like a potentially lucrative new business!
As for color matching, by far the easiest thing to do is to take the
panel over to your local paint store and let them use their
com
> Real tuning form Accutrons are collectibles now, and it is not
> unheard of for
> an unscrupulous watchmaker to steal the movement out of one, and
> replace it with
> a cheap quartz movement, all in the name of doing the watch's owner
> a favor.
Not just unscrupulous watchmakers, that's wh
On Nov 25, 2007, at 7:17 PM, Mike Feher wrote:
> Well, this may seem like a dumb question to some of you, but, it
> does have
> me baffled a little. I have noticed some time ago that the time
> indicated on
> my cell phone is usually two to four seconds ahead of GPS time.
Ahead? Now that is
); SAEximRunCond expanded to false
Errors-To: [EMAIL PROTECTED] RETRY
> If the sample rate is 44.1 kHz then the adev below 1 s, even
> down to 10 us, or jitter, or the phase noise above 1 kHz are
> they key parameters; not long-term drift. In this case I'd take
> a nice 10811A over a typical Rb an
While on the topic of Sputnik, y'all might want to give this a listen:
http://www.prometheus-music.com/audio/surprise.mp3
I heartily recommend the whole album:
http://www.totouchthestars.com/
OK, not really a time related post...except for the clock in the CD
player...which begs the question,
); SAEximRunCond expanded to false
Errors-To: [EMAIL PROTECTED] RETRY
> I was amazed a couple of months ago to find about 20 - 30% of all all
> offerings for HDTV cameras to be bogus.
The percentage is even higher for thermal imagers.
Had one guy list his location as being in the next town over
Ah, but what if one used the tunnel itself as a waveguide, and
propagated an RF signal down it? Would it then reliably arrive at all
the points, with a known delay?
Since the tunnels are probably at least ten meters wide and tall,
that's a pretty low frequency, which is easy to generate, and n
Neat! What's that doing there?
Heard very weakly in Rhode Island this evening. Only the minute tones
were clear, the ticks were much harder to hear, there being a normal
broadcaster on the frequency also audible.
Tom Frank, KA2CDK
On May 1, 2007, at 7:52 PM, Rich and Marcia Putz wrote:
> Hi
On Apr 20, 2007, at 5:28 PM, Hal Murray wrote:
>> John (who still wears a mechanical watch)
>
> Speaking of mechanical watches...
>
> Does anybody make good ones anymore?
Define "good".
For wrist watches, if you mean fairly accurate (blasphemy here to
suggest only fairly, I know), yes, there a
> PS. I *still* have perfectly good hearing! I was never hit by even a
> temporary
> run of rings in the ears when doing PA. I've only had a tone popping up
> breifly at other times. Just enought to make me notice them but then
> gone not
> too much later. This can be due to stress.
Or high blo
> Take a look at this "Aromatherapy and Audiophools" which appeared in
> Electronics World and Wireless World, October 1999. I thought it was so
> funny I scanned it and stuck it on my web site.
Wonderful! Many thanks for that.
My favorite story in this department involved a visit to a friend w
That would be the 21-1850 (typo).
Sorry.
Tom Frank
On Apr 17, 2007, at 8:47 PM, Thomas A. Frank wrote:
>> BTW, one digital power meter that I gave up on is:
>> http://www.brandelectronics.com/meters.html
>> Would appreciate any comments you have on this.
>
> I'd be
> BTW, one digital power meter that I gave up on is:
> http://www.brandelectronics.com/meters.html
> Would appreciate any comments you have on this.
I'd be curious to know what problem you had.
I've been using the 1851, and found it reliable and accurate. And it
works just as well on 400 Hz pow
> I'll give you a recent example. I have a bunch of AC power
> meters in my lab (model: Watts Up PRO) that have RS232
> output and I wrote software that logs and plots the data. A
> while back I picked up cheap serial-ethernet converters and
> now I get all the same data over my house LAN. If these
Jim;
I would suggest that the most accurate self contained wrist watch you
can get is the Synchronar 2100 Mk IV, after you've adjusted it.
It uses a fairly high frequency crystal (~700 kHz or so as I recall),
and a digital divider you can set externally, in increments of 8
seconds per year.
I
Hello All;
I apologize for this slightly off topic question, but can anyone
recommend any interesting surplus places (where one might find say a
5062...) in the following places:
Hunstville (or Birmingham), AL
Seattle, WA (other than the Boeing surplus store...I already visit
there each trip
> Are there actually US people on this list who actually continue to
> advocate the use of non-metric units in their country? Speak up!
Of course.
> Well the USA ever go metric?
No.
> I find it hard to understand why a country as advanced as the US sticks
> with such an antiquated system. I don
>> The test is called the "hammer blow" test.
>
> Why do I picture a large steel hammer on a swing setup with a DUT as
> targeted
> endpoint?
Because that's pretty much how it's done :-)
OK, the DUT is sitting on a big steel table and the hammer hits the
table not the piece, but still...you wo
> This is the basic problem with our hobby... I proudly tell people that
> I
> can measure time to trillionths of a second, but am hard pressed for a
> good answer when they ask "why do you need to?"
"For the money, for the glory, and for the fun. But mostly for the
fun..."
(with apologies to
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