Do you know anything about celestial navigation?

What's important in the software?
http://opencpn.org/ocpn/node/143

Other than sighting Polaris' angle from the horizon, and noting that the sun
rises in the east and sets in the west, I have never had a need for
celestial navigation software on Android.

However, I want to test out celestial navigation, on a lark mostly, but more
to learn how it's done (in case I ever need it in an emergency) and to show
a high school math teacher how its done so she can use it to make trig more
interesting to her students.

Looking up celestial navigation software, I find plenty of paywa
https://play.google.com/store/apps/d...id=com.vikrant
https://play.google.com/store/apps/d...ics.app.celnav
https://play.google.com/store/apps/d...otz.starstruck
http://appcrawlr.com/android/observa...celestial-body
etc.

But it's standard policy to never buy the payware until you've exhausted the
freeware, if for no other reason than you *know* exactly what you need the
payware to do if/when the freeware fails. (99% of the time or more, the
freeware does what you need, at least on Android.)

Looking up the freeware celestial navigation software, I find:
https://play.google.com/store/apps/d...stroNavigation
https://play.google.com/store/apps/d...Sightreduction
https://play.google.com/store/apps/d...stialnavigator

All I ask in this thread are the basic questions anyone new to celestial
navigation would ask:
a. What freeware is the best one to try out first?
b. What are the minimum required features of that freeware

On Sun, 27 Nov 2016 16:01:33 +0000 (UTC), Raymond Spruance III wrote:
Do you know anything about celestial navigation?

--- big snip --

All I ask in this thread are the basic questions anyone new to
celestial navigation would ask:

And you _just had_ to cross-post this to sci.electronics.repair ... why?

On Sun, 27 Nov 2016 16:01:33 +0000 (UTC), Raymond Spruance III
wrote:

Do you know anything about celestial navigation?

Yep.

I want to test out celestial navigation, on a lark mostly, but more
to learn how it's done (in case I ever need it in an emergency) and to show
a high school math teacher how its done so she can use it to make trig more
interesting to her students.

You're unlikely to have a working Android device available in an
emergency. At best, a WWV/WWVB receiver, reasonable accurate clock,
and HO229 sight reduction tables or this years nautical almanac. If
you're going to impress a math teacher, then *YOU* get to do the
required math, not the computah. The only thing the computah does is
replace the tables and save you from the pain of interpolation. You
still have to do 3 other sextant sight corrections (index error, dip,
altitude correction). You can download HO229 or the nautical almanac
from:
http://thenauticalalmanac.com

There are plenty of instructional videos on YouTube under "how to use
a sextant" and such. Most deal with a noon sight, which is where you
start. Since you're likely to be doing this on land, instead of at
sea, you'll need an artificial horizon for your sextant.
http://www.davisnet.com/product/artificial-horizon/

The rest is RTFM, arithmetic, and practice. Once you've mastered the
noon sight, try using the moon or stars. If you want a lesson in
reality, find a suitable sailboat, wrap one arm around the mast, and
then try taking a series of noon sights.

All I ask in this thread are the basic questions anyone new to celestial
navigation would ask:
a. What freeware is the best one to try out first?

The free Nautical Almanac. It's in PDF form so you can display it on
a laptop, eBook reader, or whatever while you do the math by hand.

b. What are the minimum required features of that freeware

Ummm... that it's free? If you want to learn navigation, you're going
to need to learn about celestial mechanics, navigational conventions,
a fair number of new terms, and what happens when you're in a
different part of the planet. You could learn those from a computah
program that offers a tutorial, but I believe these are best learned
with paper and pen. Once you're proficient with the process, then you
can use the computer to allegedly save you some time.

Good luck and have fun.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sun, 27 Nov 2016 10:09:46 -0800, Jeff Liebermann wrote:

You're unlikely to have a working Android device available in an
emergency.

You're right Jeff, but one nice thing about knowledge is that you have
*that* always with you, even in an emergency.

So, one goal, always, is to *learn* how to do celestial navigation, where,
in a pinch, you can approximate given the experience gained using the
battery operated tools.


At best, a WWV/WWVB receiver, reasonable accurate clock,
and HO229 sight reduction tables or this years nautical almanac.

Really on the accurate clock? C'mon. I'll bet a five-dollar digital watch
has better accuracy than all the navigators had in the age of exploration.

If
you're going to impress a math teacher, then *YOU* get to do the
required math, not the computah.

Yes. Indeed. But I would like the help of the instruments and the
calculations, since, half of math is just intuition on how to do it (which
is gained by being right before, when you have more tools available).

The only thing the computah does is
replace the tables and save you from the pain of interpolation.

Fine with me.

You
still have to do 3 other sextant sight corrections (index error, dip,
altitude correction).

Can a plastic protractor substitute for a sextant for our purposes?
(i.e., it's more the process than the accuracy that I'm after.)

You can download HO229 or the nautical almanac from:
http://thenauticalalmanac.com

Egads. 250 pages. For 2016 only! Another 250 pages for 2017.
Plus 180 Megabytes of celestial stuff.

Wow. There's a *lot* of learning that needs to be accomplished.
I thought it was just a sighting of about 60 stars!

There are plenty of instructional videos on YouTube under "how to use
a sextant" and such. Most deal with a noon sight, which is where you
start.

Ah, Jeff. Thanks for letting me know where you sight. Seems to me a "noon
sighting" is easy. stick a twig in the ground, mark when the shadow switches
from west to east, and bingo. That's noon at your longitude when compared
with GMT, and, voila!

I guess a noon longitude is as simple, using a rough estimate of the angle
from the horizon to the sun. Bingo. Latitude.

Since you're likely to be doing this on land, instead of at
sea, you'll need an artificial horizon for your sextant.
http://www.davisnet.com/product/artificial-horizon/

Interesting. A $32 artificial horizon. Who knew that's needed?

Seems to me a bubble meter should work as well. Right?
Can't the phone bubble meter work for an artificial horizon?

Anyway, you are correct these are land sightings.
In mountains. Santa Cruz mountains.

The rest is RTFM, arithmetic, and practice. Once you've mastered the
noon sight, try using the moon or stars. If you want a lesson in
reality, find a suitable sailboat, wrap one arm around the mast, and
then try taking a series of noon sights.

Thanks for the suggestion of starting with a noon sight, and then a moon
sight (must be a sailor's rhyme there somewhere). And yes, I get seasick,
so, I'm intimately familiar with the reality of the motion of the ocean (I
give Captain William Bligh a lot of credit for what he done did).

a. What freeware is the best one to try out first?

The free Nautical Almanac. It's in PDF form so you can display it on
a laptop, eBook reader, or whatever while you do the math by hand.

Very interesting that this PDF is all that is needed (along with a sextant
and an artificial horizon, both of which should be phone tools if you ask
me).
2017: https://thenauticalalmanac.com/2017%...%20Almanac.pdf
2016: https://thenauticalalmanac.com/2016%...%20Almanac.pdf


b. What are the minimum required features of that freeware

Ummm... that it's free? If you want to learn navigation, you're going
to need to learn about celestial mechanics, navigational conventions,
a fair number of new terms, and what happens when you're in a
different part of the planet.

For now, Jeff, I'm gonna be at around 35 to 40 degrees North and about 120
to 122 degrees West. After I get good at that, I can work on the other
angles.

You could learn those from a computah
program that offers a tutorial, but I believe these are best learned
with paper and pen. Once you're proficient with the process, then you
can use the computer to allegedly save you some time.

Thanks for the advice. What would be nice is learning how to do dead
reckoning with the phone as the artificial horizon and sextant and a few
well-known start (e.g., Polaris) as the frame of reference.

On Sun, 27 Nov 2016 18:54:08 -0000 (UTC), Raymond Spruance III wrote:

Can a plastic protractor substitute for a sextant for our purposes?

Here are PDF almanacs:
http://thenauticalalmanac.com

Tools needed should all be on Android for free:
a. sextant (tutorial https://www.youtube.com/watch?v=qsErtrttJsY)
b. artificial horizon (tutorial https://www.youtube.com/watch?v=B5Ud9iPW-yk)
c. almanac (tutorial https://www.youtube.com/watch?v=p6znyx0gjb4

For example:
A. Android Sextant App by Talltree Softwa
https://play.google.com/store/apps/d...tor.nightsky20

B. Aircraft Horizon Free by Sensorworks
https://play.google.com/store/apps/d...fthorizon_free

C. Google Sky Map:
https://play.google.com/store/apps/d...roid.stardroid

In article ,
says...

Really on the accurate clock? C'mon. I'll bet a five-dollar digital watch
has better accuracy than all the navigators had in the age of exploration.

But explorers, by definition, don't need to know exactly where they are
because they don't have accurate charts anyway! Not to mention a lot of
them came to grief...

Mike.

MJC wrote:

But explorers, by definition, don't need to know exactly where they are
because they don't have accurate charts anyway! Not to mention a lot of
them came to grief...

The early explorers used plenty of charts and tables though!

Peter Hakel has made many spreadsheets for Celnav that are useful.
http://www.navigation-spreadsheets.c...triangles.html

A perfect Sun sight reduction spreadsheet can be obtained here.
http://backbearing.com/excel.html

Erik Deman has all of the Nautical Almanac information on his site.
http://www.siranah.de/

You can get HO 249 Volumes 1, 2 and 3 here;
https://www.celestaire.com/pubs/category/3-pub-249.html

Fair winds and clear skies.

On Sun, 27 Nov 2016 18:54:08 -0000 (UTC), Raymond Spruance III
wrote:

On Sun, 27 Nov 2016 10:09:46 -0800, Jeff Liebermann wrote:

You're unlikely to have a working Android device available in an
emergency.

You're right Jeff, but one nice thing about knowledge is that you have
*that* always with you, even in an emergency.

I'm not sure what manner of emergency would require knowing your exact
location using a sextant, but I would guess(tm) that it's either
nautical or aeronautical. Somehow, I don't see you tramping around
the woods with a sextant. If you're on land, can see some landmarks,
and have a map, you don't need a sextant. Therefore, unless you're
planning to go sailing or flying, a sextant isn't going to be much
help, even with an Android phone (which has a GPS receiver).

So, one goal, always, is to *learn* how to do celestial navigation, where,
in a pinch, you can approximate given the experience gained using the
battery operated tools.

Ok, a hybrid approach. I'm more of a purist, but that's fine. As I
mumbled, all that an Android app buys you is a laundry list of boxes
to fill with numbers, a scratch pad, and if the program is really
good, a sanity check.

At best, a WWV/WWVB receiver, reasonable accurate clock,
and HO229 sight reduction tables or this years nautical almanac.

Really on the accurate clock? C'mon. I'll bet a five-dollar digital watch
has better accuracy than all the navigators had in the age of exploration.

I'll take the bet. First, you only need an accurate clock if you want
to obtain your latitude. Longitude can be done with just a noon
sight. Latitude requires a clock.

Find yourself a copy of "Longitude: The True Story of a Lone Genius
Who Solved the Greatest Scientific Problem of His Time"
https://en.wikipedia.org/wiki/Longitude_(book)
There are also some YouTube videos on the topic of Longitude:
https://www.youtube.com/watch?v=ecrf8KhVcyo (3hrs)
https://www.youtube.com/watch?v=NENPdT4LASw (54 min Nova version)
There's quite a bit there on how navigation was done in the 18th
century including the accuracy of the various John Harrison clocks.

"John Harrison's 'longitude' clock sets new record - 300 years on"
http://www.independent.co.uk/news/science/john-harrisons-longitude-clock-sets-new-record-300-years-on-10187304.html
One second in 100 days (on land). The target value for an acceptable
clock was 1 minute in 50 days.

I don't want to get into a rant on the accuracy of todays digital
watches. Everything is dependent on the stability of the tuning for
crystal, with is far from temperature stable. I just dug out the
specs for a random Casio wris****ch. About +/-12 sec per month at
room temp and who knows over a reasonable temperature range. I'm sure
someone has done some testing, but I'm late for a free lunch, so you
get to Google for the numbers.

Can a plastic protractor substitute for a sextant for our purposes?
(i.e., it's more the process than the accuracy that I'm after.)

No, unless you're only interested in knowing which state you're in.
Also, the optics one a sextant are designed to protect your eyes.
Prior to the sextant, the use of a cross staff required staring at the
sun, a really bad idea.

You can download HO229 or the nautical almanac from:
http://thenauticalalmanac.com

Egads. 250 pages. For 2016 only! Another 250 pages for 2017.
Plus 180 Megabytes of celestial stuff.

You're not expected to read it cover to cover. On the average, you'll
use 3 or 4 pages at a time. However, for every sighting, all 3 or 4
pages are different.

Wow. There's a *lot* of learning that needs to be accomplished.
I thought it was just a sighting of about 60 stars!

Stop complaining and start reading.

Since you're likely to be doing this on land, instead of at
sea, you'll need an artificial horizon for your sextant.
http://www.davisnet.com/product/artificial-horizon/

Interesting. A $32 artificial horizon. Who knew that's needed?

You can build your own:
https://thenauticalalmanac.com/Artificial%20Horizon.html

Seems to me a bubble meter should work as well. Right?
Can't the phone bubble meter work for an artificial horizon?

Neither is accurate. Bolting a bubble level onto the sextant is that
way its done on aeronautical sextants as the sloshing of the liquid in
the larger reflection type artificial horizon doesn't work well on a
vibrating airplane.

Thanks for the suggestion of starting with a noon sight, and then a moon
sight

The moon is tricky. It moves quite rapidly across the field of vision
and is therefore difficult to get an accurate measurement.

Thanks for the advice. What would be nice is learning how to do dead
reckoning with the phone as the artificial horizon and sextant and a few
well-known start (e.g., Polaris) as the frame of reference.

I can tell this is not going to be a classical lesson in navigation.
No, you can't borrow any of my sextants.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 27 Nov Allodoxaphobia scrit:

And you _just had_ to cross-post this to sci.electronics.repair

Too bad it wasn't cross posted to the windows ng.
They could use this information below.

1. TeaCup http://www.teacupnavigation.net/CN.html
2. StarCalc http://www.relex.ru/~zalex/main.htm
3. SeaClear http://www.sping.com/seaclear/

1. Teacup Navigation has free celestial software and a free book in PDF
format for downloading. The book teaches the concepts and techniques of
celestial navigation, some interesting history, and computational methods
using a simple pocket scientific calculator. The book also has condensed
tables and work sheets for when you have no calculators available. It also
shows how to build your own navigational tools. The free comprehensive
celestial navigation software is for the Windows operating system. It will
run in Ubuntu (Linux) when "Wine" software is also installed. The same is
true for a Mac when the Mac version of Wine is used. The Teacup Navigation
site is at http://www.teacupnavigation.net/CN.html

2. StarCalc is a free program that will bring a planetarium onto your
computer monitor. The program is a creation of Alexander E. Zavalishin, a
Russian, and is provided at no charge. This program will show a picture of
the sky at any time of the day or night from any location in the world at
any time. The program provides an alternative to the "Star Finder" plastic
circular slide rule used in the JN and N courses. Using the program, you can
print a copy of the sky showing the bodies that you intend to "shoot". The
graphic provided by StarCalc gives a clear diagram of where the celestial
targets of opportunity are located and the hassle of plotting solar system
objects is eliminated. The StarCalc program can be downloaded from:
http://www.relex.ru/~zalex/main.htm

3. SeaClear is a freeware navigation program for Windows NT 4.0, 2000 or
95/98/ME which, when connected to a GPS (or other unit capable of
transmitting NMEA position data), will display the vessel on a chart, with
the current position, speed and direction. New charts are loaded as needed.
The track may be saved to a file for later reviewing, and log book entries
may be manually and automatically entered. An unlimited number of routes and
waypoints may be created and used to assist in the navigation. The screen
area for charts is maximized with most functions accessed with the right
mouse button. Zooming is provided with support for IntelliMouse wheel. The
program may be downloaded from: http://www.sping.com/seaclear/

On Sun, 27 Nov 2016 14:40:54 -0800, Jeff Liebermann
wrote:

I'll take the bet. First, you only need an accurate clock if you want
to obtain your latitude. Longitude can be done with just a noon
sight. Latitude requires a clock.

Sigh. No brain today. That should be Latitude can be done with a
noon sight while longitude requires a clock. Dyslexia induced by
schlepping a 150 lb drill press up about 40 stairs.

I don't want to get into a rant on the accuracy of todays digital
watches. Everything is dependent on the stability of the tuning for
crystal, with is far from temperature stable. I just dug out the
specs for a random Casio wris****ch. About +/-12 sec per month at
room temp and who knows over a reasonable temperature range. I'm sure
someone has done some testing, but I'm late for a free lunch, so you
get to Google for the numbers.

For a common digital clock:
https://en.wikipedia.org/wiki/Quartz_clock#Accuracy
"...a typical quartz clock or wris****ch will gain or
lose 15 seconds per 30 days (within a normal temperature
range of 5 °C/41 °F to 35 °C/95 °F) or less than a half
second clock drift per day when worn near the body."

or a marine chronometer:
https://en.wikipedia.org/wiki/Marine_chronometer#Today
"...even in wrist watches such as the Omega Marine Chronometer,
that are accurate to within 5 or 20 seconds per year."

Incidentally, be careful what you use for a clock. GPS time is
currently 17 seconds ahead of UTC (WWV/WWVB) time:
http://www.leapsecond.com/java/gpsclock.htm
For navigation, you want GMT, UTC or UT1 (all the same). Most GPS
receivers and smartphones correct for this, but not every smartphone
manufacturer got the memo:
http://802.11junk.com/jeffl/crud/GPS-vs-UTC.jpg
Best to check your smartphone:
60 nautical miles = 1 degree of latitude
1 nautical mile = 6076ft
60 NM/sec * 6076ft/NM / 3600 sec/deg= 101 ft/second
Therefore the 17 second difference between GMT and UTC will produce an
error of about 1,717 ft (about 1/4th nautical mile) in longitude at
the equator and lesser errors at higher latitudes.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sun, 27 Nov 2016 17:27:31 -0800, Jeff Liebermann wrote:

Sigh. No brain today. That should be Latitude can be done with a
noon sight while longitude requires a clock. Dyslexia induced by
schlepping a 150 lb drill press up about 40 stairs.

You had me scared, Jeff, when you flipped the coordinate system on me.

I'm currently reading this book, so hopefully I'll be slightly more
educumated when I next write back.
Celestial Navigation in a Teacup, by Rodger E. Farley
http://www.teacupnavigation.net/Cele...a_Teacup_v.pdf

The goal is to give the math teacher a lesson for her high school kids,
using freeware, where most are on iOS but some are on Android.

On Mon, 28 Nov 2016 04:05:54 -0000 (UTC), Raymond Spruance III
wrote:
You had me scared, Jeff, when you flipped the coordinate system on me.

My proof reader and copy editor both missed my mistake.

I'm currently reading this book, so hopefully I'll be slightly more
educumated when I next write back.
Celestial Navigation in a Teacup, by Rodger E. Farley
http://www.teacupnavigation.net/Cele...a_Teacup_v.pdf

Looks quite good from a quick skim.

The book assumes a working knowledge of geometry and trigonometry
which might be suitable for a high skool level class. I think her
biggest problem will be adding about 30 navigational terms to the
students vocabulary. A navigation glossary might be useful. For
example:
http://www.diy-wood-boat.com/Navigation_terms.html

The goal is to give the math teacher a lesson for her high school kids,
using freeware, where most are on iOS but some are on Android.

Like I suggested. Lose the apps and computah programs initially.
Those can come later. Learn navigation with tables, paper, pen,
calculator, slide rule, etc. I don't know if they're going to be
plotting a course, but plotting sheets might be useful. Once you make
it past the geometry and basic concepts, the rest is just math.
However, my guess(tm) is that the teacher will become bogged down in
the terminology and geometry. Due to lack of time, she will not get
very far into practical navigation. At best probably a demonstration.

One problem is getting students a sextant for practice. Even the
cheapest plastic sextant (Davis 3) is $50. Make their own sextant,
octant, or quadrant?
http://www.tecepe.com.br/nav/CDSextantProject.htm
http://www.science-teachers.com/space/north_star/HowtoMakeaSextant.doc
http://www.tecepe.com.br/nav/XTantProject.htm
Make sure it has eye protection. I first learned navigation in a
class of about 25 aspiring nautical types. Most brought their own
sextants of varying quality. We took turns practicing sun sights with
everyone using those numbers. I would not expect a high skool student
to buy a sextant.

Good luck.
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 2016-11-27, Raymond Spruance III wrote:
On Sun, 27 Nov 2016 10:09:46 -0800, Jeff Liebermann wrote:

You're unlikely to have a working Android device available in an
emergency.

You're right Jeff, but one nice thing about knowledge is that you have
*that* always with you, even in an emergency.

So, one goal, always, is to *learn* how to do celestial navigation, where,
in a pinch, you can approximate given the experience gained using the
battery operated tools.


At best, a WWV/WWVB receiver, reasonable accurate clock,
and HO229 sight reduction tables or this years nautical almanac.

Really on the accurate clock? C'mon. I'll bet a five-dollar digital watch
has better accuracy than all the navigators had in the age of exploration.

Not many quartz watches qualify as 'chronometers' for navigation
purposes. Best practice on ships is to have more than one chronometer
on board, and know the 'rate' of each (ie how much it gains or loses
each day, usually established by an observatory), and have them wound up
and cared for by a designated officer and no-one else. These are used
to maintain the accuracy of the watches actually used for observations.

But in an emergency, yes, any reliable watch is better than nothing. As
long as the battery doesn't fail.

If
you're going to impress a math teacher, then *YOU* get to do the
required math, not the computah.

Yes. Indeed. But I would like the help of the instruments and the
calculations, since, half of math is just intuition on how to do it (which
is gained by being right before, when you have more tools available).

The only thing the computah does is
replace the tables and save you from the pain of interpolation.

Fine with me.

You
still have to do 3 other sextant sight corrections (index error, dip,
altitude correction).

Can a plastic protractor substitute for a sextant for our purposes?
(i.e., it's more the process than the accuracy that I'm after.)

Consider at least looking at information about the 'astrolabe'; also
later developments such as the 'quadrant' and 'back-staff' which
preceded the 'sextant', all of which are within the scope of
'handicraft' or 'model-makers' to make (albeit not as accurately as a
skilled instrument maker, but a lot cheaper!). I've even used a
cardboard astrolabe to get fairly accurate time and latitude
measurements. Once you've used an astrolabe, it's easier to grasp what
a modern sextant is doing.

As well as maths and so on, this brings in history and culture and
geography - and even literature (Chaucer wrote a little treatise on the
astrolabe to instruct his son).

You can download HO229 or the nautical almanac from:
http://thenauticalalmanac.com

Egads. 250 pages. For 2016 only! Another 250 pages for 2017.
Plus 180 Megabytes of celestial stuff.

Wow. There's a *lot* of learning that needs to be accomplished.
I thought it was just a sighting of about 60 stars!

There are plenty of instructional videos on YouTube under "how to use
a sextant" and such. Most deal with a noon sight, which is where you
start.

Ah, Jeff. Thanks for letting me know where you sight. Seems to me a "noon
sighting" is easy. stick a twig in the ground, mark when the shadow switches
from west to east, and bingo. That's noon at your longitude when compared
with GMT, and, voila!

I guess a noon longitude is as simple, using a rough estimate of the angle
from the horizon to the sun. Bingo. Latitude.

Since you're likely to be doing this on land, instead of at
sea, you'll need an artificial horizon for your sextant.
http://www.davisnet.com/product/artificial-horizon/

Interesting. A $32 artificial horizon. Who knew that's needed?

Seems to me a bubble meter should work as well. Right?
Can't the phone bubble meter work for an artificial horizon?

Anyway, you are correct these are land sightings.
In mountains. Santa Cruz mountains.

Any horizontal reflecting surface will do, eg a lake or strategically
placed bowl of water. The nifty gadget is convenient, not essential.

(Astrolabes and quadrants don't need any sort of horizon, they use
gravity to establish the vertical plane).

[...]

--
-- ^^^^^^^^^^
-- Whiskers
-- ~~~~~~~~~~

On Sunday, November 27, 2016 at 11:01:40 AM UTC-5, Raymond Spruance III wrote:

Is trolling again under a different alias.

Please let this one stay a small thread!

Peter Wieck
Melrose Park, PA

On Mon, 28 Nov 2016 18:49:20 +0000, Whiskers
wrote:

Not many quartz watches qualify as 'chronometers' for navigation
purposes.

If it's certified by the COSC, then it's a chronometer:
https://en.wikipedia.org/wiki/COSC
Only a fairly small number of watches are certified.

The specs allow a mechanical clock a daily rate of
-4/+6 sec/day = 2.5 minutes/month = 30 min/year.

However, a crystal controlled clock is only allowed
+/-0.07 sec/day = 2.1 sec/month = 25.2 sec/year.

There are now better clocks that easily meet the COSC requirements:
http://www.leapsecond.com/pages/atomic-bill/
https://www.kickstarter.com/projects/846511652/the-worlds-first-true-atomic-wris****ch-the-cesium
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 11/28/2016 08:34 PM, Jeff Liebermann wrote:
On Mon, 28 Nov 2016 18:49:20 +0000, Whiskers
wrote:

Not many quartz watches qualify as 'chronometers' for navigation
purposes.

If it's certified by the COSC, then it's a chronometer:
https://en.wikipedia.org/wiki/COSC
Only a fairly small number of watches are certified.

The specs allow a mechanical clock a daily rate of
-4/+6 sec/day = 2.5 minutes/month = 30 min/year.

However, a crystal controlled clock is only allowed
+/-0.07 sec/day = 2.1 sec/month = 25.2 sec/year.

There are now better clocks that easily meet the COSC requirements:
http://www.leapsecond.com/pages/atomic-bill/
https://www.kickstarter.com/projects/846511652/the-worlds-first-true-atomic-wris****ch-the-cesium

In [possibly] 2008 we bought some Casio 'atomic' watches with solar
batteries at Costco for ~$25 each plus tax. The same watches are
generally available for $100 now. Not only are they incredibly
accurate due to receiving nightly hits from the atomic clock in [I
believe] Boulder CO, the black plastic bands show no sign of wearing
out, unlike the bands on previous Casio digital watches I've had.

There's nothing quite like owning a truly accurate timepiece :-)


--
Cheers, Bev
"The fact that windows is one of the most popular ways to
operate a computer means that evolution has made a general
****up and our race is doomed." -- Anon.

On 2016-11-29 08:27, The Real Bev wrote:
On 11/28/2016 08:34 PM, Jeff Liebermann wrote:
On Mon, 28 Nov 2016 18:49:20 +0000, Whiskers
wrote:

However, a crystal controlled clock is only allowed
+/-0.07 sec/day = 2.1 sec/month = 25.2 sec/year.

There are now better clocks that easily meet the COSC requirements:
http://www.leapsecond.com/pages/atomic-bill/
https://www.kickstarter.com/projects/846511652/the-worlds-first-true-atomic-wris****ch-the-cesium


In [possibly] 2008 we bought some Casio 'atomic' watches with solar
batteries at Costco for ~$25 each plus tax. The same watches are
generally available for $100 now. Not only are they incredibly
accurate due to receiving nightly hits from the atomic clock in [I
believe] Boulder CO, the black plastic bands show no sign of wearing
out, unlike the bands on previous Casio digital watches I've had.

There's nothing quite like owning a truly accurate timepiece :-)

But it is not a "truly accurate timepiece", in the sense that it is not
autonomous. It needs a sync signal from outside.

And I hope it is well built... I have a wall clock that syncs every
night (about 3 AM) from a radio signal from Germany, I think. The rest
of the day it runs autonomously.

https://en.wikipedia.org/wiki/Radio_clock

However, sometimes there is some problem and it is 15 hours off sync.
Depending on the model, it can manage to sync the next day, or never. I
can not really trust it.

--
Cheers, Carlos.

On 11/29/2016 09:07 AM, Carlos E.R. wrote:
On 2016-11-29 08:27, The Real Bev wrote:
On 11/28/2016 08:34 PM, Jeff Liebermann wrote:
On Mon, 28 Nov 2016 18:49:20 +0000, Whiskers
wrote:

However, a crystal controlled clock is only allowed
+/-0.07 sec/day = 2.1 sec/month = 25.2 sec/year.

There are now better clocks that easily meet the COSC requirements:
http://www.leapsecond.com/pages/atomic-bill/
https://www.kickstarter.com/projects/846511652/the-worlds-first-true-atomic-wris****ch-the-cesium

In [possibly] 2008 we bought some Casio 'atomic' watches with solar
batteries at Costco for ~$25 each plus tax. The same watches are
generally available for $100 now. Not only are they incredibly
accurate due to receiving nightly hits from the atomic clock in [I
believe] Boulder CO, the black plastic bands show no sign of wearing
out, unlike the bands on previous Casio digital watches I've had.

There's nothing quite like owning a truly accurate timepiece :-)

But it is not a "truly accurate timepiece", in the sense that it is not
autonomous. It needs a sync signal from outside.

I suspect that if Boulder stops sending sync signals the microsecond
accuracy of my watch will NOT be on my top-ten problem list :-)

And I hope it is well built... I have a wall clock that syncs every
night (about 3 AM) from a radio signal from Germany, I think. The rest
of the day it runs autonomously.

https://en.wikipedia.org/wiki/Radio_clock

However, sometimes there is some problem and it is 15 hours off sync.
Depending on the model, it can manage to sync the next day, or never. I
can not really trust it.

Occasionally it doesn't get an update, probably because I was moving
around during the syncing process -- I'm not a good sleeper.
Unfortunately, I have no way of judging the resulting inaccuracy.

--
Cheers, Bev
"I read about this syndrome called hypochondria in a
magazine. I think I've got it." -- DA

On Mon, 28 Nov 2016 23:27:33 -0800, The Real Bev
wrote:

In [possibly] 2008 we bought some Casio 'atomic' watches with solar
batteries at Costco for ~$25 each plus tax. The same watches are
generally available for $100 now. Not only are they incredibly
accurate due to receiving nightly hits from the atomic clock in [I
believe] Boulder CO, the black plastic bands show no sign of wearing
out, unlike the bands on previous Casio digital watches I've had.
There's nothing quite like owning a truly accurate timepiece :-)

The nightly updates can be a problem. Propagation from WWVB is rather
lousy during the daylight hours, and only improves on the left coast
around midnight.
http://tf.nist.gov/stations/wwvbcoverage.htm
http://tf.nist.gov/tf-cgi/wwvbmonitor_e.cgi
It's not lack of signal that causes problems. It's interference. It's
not uncommon for updates to fail if the watch is left in an RF noisy
location, such as next to an operating switching power supply.

Orientation is also a problem. Put the watch down with the tiny
loopstick pointed at WWVB and you get no signal even if propagation is
good. This is a lousy noisy signal with the end pointed at WWVB:
http://802.11junk.com/jeffl/WWVB%20test/end-pointed-at-WWVB.jpg
This is what a good signal looks like with the loopstick broadside to
WWVB:
http://802.11junk.com/jeffl/WWVB%20test/loopstick-perpendicular-to-WWVB.jpg
Even cross polarization will produce a lousy signal. This is a noisy
signal with the loopstick oriented vertically:
http://802.11junk.com/jeffl/WWVB%20test/loopstick-vertical.jpg

What the watch does without WWVB updates is a matter of conjecture. I
haven't done any testing nor could I find any online. Without the
updates from WWVB, it's probably no better than a common digital
watch. Even so, that's good enough for navigation, but for accuracy
it requires WWVB updates. (4 sec error = 1 nautical mile)

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Tue, 29 Nov 2016 18:07:29 +0100, "Carlos E.R."
wrote:

And I hope it is well built... I have a wall clock that syncs every
night (about 3 AM) from a radio signal from Germany, I think. The rest
of the day it runs autonomously.

I'm surprised that it works. I think you're in Spain and DFC77
transmitter is in Germany. Spain is at the outer edge of the coverage
area:
https://en.wikipedia.org/wiki/DCF77#Reception_area
https://en.wikipedia.org/wiki/DCF77#/media/Filecf_weite.jpg

You can improve reception by moving the clock to a location where
there is less electrical interference (away from switching power
supplies, TV's, computahs, etc). Also, orienting the loopstick so
that it is horizontal and "broadside" to the direction of Germany.

However, sometimes there is some problem and it is 15 hours off sync.

That's what happens when the clock receives garbage instead of an
update. The usual algorithm is for the clock to receive two or three
valid updates in close succession before it will accept the data. If
it hears two identical noisy updates, it will display erroneous data.
It's very unlikely that this will happen, but it's not impossible. If
your clock does NOT require two or three consecutive valid updates,
it's highly likely that you will see far more garbage updates.

Depending on the model, it can manage to sync the next day, or never. I
can not really trust it.

I don't think a DFC77 clock will work reliably at your location in
Spain. Think about using NTP updates from over the internet instead.
It can easily be done with a Raspberry Pi.
http://www.satsignal.eu/raspberry-pi/DigitalClock.html
An old handheld GPS receiver, mounted on the wall will also work but
watch out for the 17 sec the GPS - UTC difference.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 2016-11-29, Jeff Liebermann wrote:
On Mon, 28 Nov 2016 23:27:33 -0800, The Real Bev
wrote:

In [possibly] 2008 we bought some Casio 'atomic' watches with solar
batteries at Costco for ~$25 each plus tax. The same watches are
generally available for $100 now. Not only are they incredibly
accurate due to receiving nightly hits from the atomic clock in [I
believe] Boulder CO, the black plastic bands show no sign of wearing
out, unlike the bands on previous Casio digital watches I've had.
There's nothing quite like owning a truly accurate timepiece :-)

The nightly updates can be a problem. Propagation from WWVB is rather
lousy during the daylight hours, and only improves on the left coast
around midnight.
http://tf.nist.gov/stations/wwvbcoverage.htm
http://tf.nist.gov/tf-cgi/wwvbmonitor_e.cgi
It's not lack of signal that causes problems. It's interference. It's
not uncommon for updates to fail if the watch is left in an RF noisy
location, such as next to an operating switching power supply.

Orientation is also a problem. Put the watch down with the tiny
loopstick pointed at WWVB and you get no signal even if propagation is
good. This is a lousy noisy signal with the end pointed at WWVB:
http://802.11junk.com/jeffl/WWVB%20test/end-pointed-at-WWVB.jpg
This is what a good signal looks like with the loopstick broadside to
WWVB:
http://802.11junk.com/jeffl/WWVB%20test/loopstick-perpendicular-to-WWVB.jpg
Even cross polarization will produce a lousy signal. This is a noisy
signal with the loopstick oriented vertically:
http://802.11junk.com/jeffl/WWVB%20test/loopstick-vertical.jpg

What the watch does without WWVB updates is a matter of conjecture. I
haven't done any testing nor could I find any online. Without the
updates from WWVB, it's probably no better than a common digital
watch. Even so, that's good enough for navigation, but for accuracy
it requires WWVB updates. (4 sec error = 1 nautical mile)

I had "atomic" wall clocks on battery as well as a bedroom clock
on ac. Worked very nice until the utility companies went with the
rf meters. Then the "atomic" clocks became drastically out of sync
& sometimes got reset to what look like an unknown timezone. Had even
tried replacement atomic wall clocks which had the same problems.

The Casio watch was nice until I had eye surgery after which I wasn't
able to see the time well without reading glasses. Have switched
to an analog faced timepiece with large numbers now.

On 2016-11-29 19:30, Jeff Liebermann wrote:
On Tue, 29 Nov 2016 18:07:29 +0100, "Carlos E.R."
wrote:

And I hope it is well built... I have a wall clock that syncs every
night (about 3 AM) from a radio signal from Germany, I think. The rest
of the day it runs autonomously.

I'm surprised that it works. I think you're in Spain and DFC77
transmitter is in Germany. Spain is at the outer edge of the coverage
area:
https://en.wikipedia.org/wiki/DCF77#Reception_area
https://en.wikipedia.org/wiki/DCF77#/media/Filecf_weite.jpg

Yes, I am at the middle of the 1500 km circle. Ie, at something like
1700 km. Those clocks are widely sold here, but they don't work on every
room. Your graph explains it, but I already suspected it.

Pity there are no nearer transmitters. A network of transmitters, probably.

You can improve reception by moving the clock to a location where
there is less electrical interference (away from switching power
supplies, TV's, computahs, etc). Also, orienting the loopstick so
that it is horizontal and "broadside" to the direction of Germany.


My clocks (I have 4) do not have a ferrite rod, like those in the
wikipedia. Unless minimal and well hidden.

However, sometimes there is some problem and it is 15 hours off sync.

That's what happens when the clock receives garbage instead of an
update. The usual algorithm is for the clock to receive two or three
valid updates in close succession before it will accept the data. If
it hears two identical noisy updates, it will display erroneous data.
It's very unlikely that this will happen, but it's not impossible. If
your clock does NOT require two or three consecutive valid updates,
it's highly likely that you will see far more garbage updates.

I guess all use the same chip, and it is faulty. Once the clock syncs
well, it should reject an update that is more than some minutes off.
Humm... but then there is the summer saving time change. But some clocks
use 3 volts instead of 1.5 and work better.


Depending on the model, it can manage to sync the next day, or never. I
can not really trust it.

I don't think a DFC77 clock will work reliably at your location in
Spain. Think about using NTP updates from over the internet instead.

I thought about that, yes, but not how to do it cheaply. A tablet would
do, but more expensive.

It can easily be done with a Raspberry Pi.
http://www.satsignal.eu/raspberry-pi/DigitalClock.html

Interesting, but complicated.

An old handheld GPS receiver, mounted on the wall will also work but
watch out for the 17 sec the GPS - UTC difference.

:-)

--
Cheers, Carlos.

On 11/29/2016 12:51 PM, lew wrote:

The Casio watch was nice until I had eye surgery after which I wasn't
able to see the time well without reading glasses. Have switched
to an analog faced timepiece with large numbers now.

Welcome to the world of the grownups!


--
Cheers, Bev
Nobody needs to speak on behalf of idiots, they manage
to speak entirely too much for themselves already.

On Tue, 29 Nov 2016 22:48:31 +0100, "Carlos E.R."
wrote:

My clocks (I have 4) do not have a ferrite rod, like those in the
wikipedia. Unless minimal and well hidden.

They have ferrite rods buried inside somewhere. Even the "atomic
wris****ch" has a tiny loopstick coil inside. Look for something like
these, which are a bit large for a wrist watch:
http://www.c-max.com.hk/en/technology/rct/rct_perp
http://www.c-max-time.com/products/showProduct.php?id=20
The key performance factor of a VLF receiver is the Q of the pickup
coil. Higher Q doesn't produce more signal, but does dramatically
reduce the inband noise levels. The higher the Q, the less noise is
picked up, and therefore the better the SNR (signal to noise radio).
Tiny rods are marginal, but do work. Big rods are much better for
reception. Big loops are even better, but without the ferrite core,
they tend to be huge.

Photos of both loops and loopsticks:
https://www.google.com/search?q=wwvb+loop+antenna&tbm=isch

It can easily be done with a Raspberry Pi.
http://www.satsignal.eu/raspberry-pi/DigitalClock.html

Interesting, but complicated.

If it were easy, it would probably not be any fun.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Tue, 29 Nov 2016 20:51:31 -0000 (UTC), lew
wrote:

I had "atomic" wall clocks on battery as well as a bedroom clock
on ac. Worked very nice until the utility companies went with the
rf meters. Then the "atomic" clocks became drastically out of sync
& sometimes got reset to what look like an unknown timezone. Had even
tried replacement atomic wall clocks which had the same problems.

Very strange and improbable. The "atomic" clock works on VLF (very
low frequency) around 60KHz. Most electrical smartmeters run spread
spectrum around 900MHz. The gas meters tend to use VHF/UHF
frequencies in the 160 and 460Mhz bands. Chances of interference
between such widely spaced frequencies is unlikely.

However, there are plenty of noise sources that will trash VLF
reception. Plasma TV's are a common problem. Switching power
supplied found in everything from battery chargers to desk lamps are
noisy. Some PV solar panels, converters, and inverters are horribly
noisy. Same with some CCFL and LED lamps. HF (high frequency) ham
radio was almost impossible at my house until I tracked down the
culprit (cheap battery charger for my cell phone).

You can actually use a 128Kbit/sec sound card to hear (and see) the
60KHz signals. By implication, you can also see the nearby noise
sources. Buy a 128Kbit/sec sound card or dongle. Download a copy of
SDR Sharp. Go noise hunting. I'm sure you'll find something you
didn't expect.

The Casio watch was nice until I had eye surgery after which I wasn't
able to see the time well without reading glasses. Have switched
to an analog faced timepiece with large numbers now.

At least you're not at the talking clock stage. My eyesight is slowly
deteriorating, but has a long way to go before I can't see a digital
clock. Oddly, I have more problems with some colors. I can't focus
on red LED's and orange Nixie tubes. It's just a big blurr without
glasses. However, the blue fluorescent displays are easily visible.
Try different colors and see if it helps.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Tue, 29 Nov 2016 09:16:51 -0800, The Real Bev
wrote:

I suspect that if Boulder stops sending sync signals the microsecond
accuracy of my watch will NOT be on my top-ten problem list :-)

Nope. Between nightly updates, the watch free runs just like an
ordinary digital watch. If it updates nightly, it doesn't have enough
time to drift too far in 24 hrs. Besides, if it updated continuously,
the updates would drain the battery. So, the WWVB receiver is powered
on only after midnight, tries a few times according to some algorith,
and then turns off for the night as soon as it gets a valid update.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Tue, 29 Nov 2016, Jeff Liebermann wrote:

On Tue, 29 Nov 2016 22:48:31 +0100, "Carlos E.R."
wrote:

My clocks (I have 4) do not have a ferrite rod, like those in the
wikipedia. Unless minimal and well hidden.

They have ferrite rods buried inside somewhere. Even the "atomic
wris****ch" has a tiny loopstick coil inside. Look for something like
these, which are a bit large for a wrist watch:
http://www.c-max.com.hk/en/technology/rct/rct_perp
http://www.c-max-time.com/products/showProduct.php?id=20
The key performance factor of a VLF receiver is the Q of the pickup
coil. Higher Q doesn't produce more signal, but does dramatically
reduce the inband noise levels. The higher the Q, the less noise is
picked up, and therefore the better the SNR (signal to noise radio).
Tiny rods are marginal, but do work. Big rods are much better for
reception. Big loops are even better, but without the ferrite core,
they tend to be huge.

That's the weird part, my Casio watch seems to be the one most likely to
sync up, so long as I orient it right when I go to bed, yet it's a
miniscule antenna.

But having opened some of the "atomic" clocks I have it's also a surprise
that the loopsticks aren't particularly long. Even the wall clock doesn't
ahve a longer loopstick than the portable.

Michael


Photos of both loops and loopsticks:
https://www.google.com/search?q=wwvb+loop+antenna&tbm=isch

It can easily be done with a Raspberry Pi.
http://www.satsignal.eu/raspberry-pi/DigitalClock.html

Interesting, but complicated.

If it were easy, it would probably not be any fun.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Ah, you did not spent the extra money ($4,400) for multiple lens in each eye
like I did.

I went from two sets of glasses to none. Watch on wrist to TV and driving.

http://www.changcataract.com/

Sorry, you have only one chance at cataract sugery.

SHF

"The Real Bev" wrote in message
news
On 11/29/2016 12:51 PM, lew wrote:

The Casio watch was nice until I had eye surgery after which I wasn't
able to see the time well without reading glasses. Have switched
to an analog faced timepiece with large numbers now.

Welcome to the world of the grownups!


--
Cheers, Bev
Nobody needs to speak on behalf of idiots, they manage
to speak entirely too much for themselves already.

"Jeff Liebermann" wrote in message
...
On Tue, 29 Nov 2016 20:51:31 -0000 (UTC), lew
wrote:

....
At least you're not at the talking clock stage. My eyesight is slowly
deteriorating, but has a long way to go before I can't see a digital
clock. Oddly, I have more problems with some colors. I can't focus
on red LED's and orange Nixie tubes. It's just a big blurr without
glasses. However, the blue fluorescent displays are easily visible.
Try different colors and see if it helps.

--
Jeff Liebermann

In between the two eyes I had several weeks with one new and one old.

The colors were oh so much better with the new eye and remain so for both
eyes.

One thing about cataract sugary, do not delay it. Your eyesight may get
worse at an increasing faster rate, I was almost blind even with one good
eye as the old eye was so bad.

SHF

On 11/29/2016 10:22 PM, Stephen H. Fischer wrote:
Ah, you did not spent the extra money ($4,400) for multiple lens in each eye
like I did.

A friend just had those (+$3K over Medicare) done, and I envy her. My
ophthodoc said that my astigmatism would make multifocal lenses worse
than simple toric lenses (+$1K over Medicare), and I believed her. I've
always had between 2 and 3 D of astigmatism on top of 2 or 3D of
farsigntedness, and nobody in nearly 60 years of wearing glasses has
ever been able to fully correct the goddam astigmatism. It's almost all
gone now, and I thought about multi-focal contacts. Optometrist who
seemed to know what he was doing said I wouldn't be happy with those
either, and suggested monovision. That works, but not as well as I'd wish.

TMI, right?

I went from two sets of glasses to none. Watch on wrist to TV and driving.

http://www.changcataract.com/

Sorry, you have only one chance at cataract sugery.

Hubby's aunt's was botched badly -- wouldn't unfold or something. Not
only couldn't she see, but it was really painful. The operation was
redone and she's OK now. Rather different from "I'd like something
better, please."

--
Cheers, Bev
"If you put the government in charge of the desert, there would
be a sand shortage within ten years." -- M. Friedman (?)

On Wed, 30 Nov 2016 00:04:30 -0500, Michael Black
wrote:

On Tue, 29 Nov 2016, Jeff Liebermann wrote:

On Tue, 29 Nov 2016 22:48:31 +0100, "Carlos E.R."
wrote:

My clocks (I have 4) do not have a ferrite rod, like those in the
wikipedia. Unless minimal and well hidden.

They have ferrite rods buried inside somewhere. Even the "atomic
wris****ch" has a tiny loopstick coil inside. Look for something like
these, which are a bit large for a wrist watch:
http://www.c-max.com.hk/en/technology/rct/rct_perp
http://www.c-max-time.com/products/showProduct.php?id=20
The key performance factor of a VLF receiver is the Q of the pickup
coil. Higher Q doesn't produce more signal, but does dramatically
reduce the inband noise levels. The higher the Q, the less noise is
picked up, and therefore the better the SNR (signal to noise radio).
Tiny rods are marginal, but do work. Big rods are much better for
reception. Big loops are even better, but without the ferrite core,
they tend to be huge.

That's the weird part, my Casio watch seems to be the one most likely to
sync up, so long as I orient it right when I go to bed, yet it's a
miniscule antenna.

But having opened some of the "atomic" clocks I have it's also a surprise
that the loopsticks aren't particularly long. Even the wall clock doesn't
ahve a longer loopstick than the portable.

No clue who said it first, but the consensus is that RF is magic.

The object of the antenna is to produce the best possible SNR, not the
strongest signal. If you replace the tiny antenna with a bigger
antenna, the WWVB signal will increase, but so will the received
atmospheric noise level, resulting in no net improvement in SNR. What
will change is the Q (essentially the bandwidth) of the receiver front
end. A low Q wide band loopstick will pickup far more atmospheric
noise than a high Q narrow band loopstick.

Notice how the atmospheric noise (mostly from lightning) increases
dramatically as the frequency goes down:
https://en.wikipedia.org/wiki/Atmospheric_noise
https://en.wikipedia.org/wiki/Atmospheric_noise#/media/File:Atmosphericnoise.PNG

Of course, there's a limit to how small a practical loopstick can be
built. Mostly, the size of the wire to wind the loopstick, its
resistance, and the characteristics of the ferrite material, set the
lower limit. The loopsticks can be made smaller, if you can afford
the fine wire needed to get enough turns.

There's also an upper limit to the size of the loopstick. It's
possible to have such a high Q, that the bandwidth of the WWVB signal
(about 5Hz) will not fit within the loopstick bandwidth. Temperature
and mechanical stability will also be a problem with very high Q
loopsticks. Orientation sensitivity also becomes somewhat of a
problem.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Tue, 29 Nov 2016 22:30:26 -0800, "Stephen H. Fischer"
wrote:

In between the two eyes I had several weeks with one new and one old.
The colors were oh so much better with the new eye and remain so for both
eyes.
One thing about cataract sugary, do not delay it. Your eyesight may get
worse at an increasing faster rate, I was almost blind even with one good
eye as the old eye was so bad.

Thanks. I'm 68 solar revolutions old, so that's a real possibility.
No sign of cataracts, but I'm borderline with glaucoma. Some of my
friends have had cataract surgery and opted for strange combinations,
such as one eye optimized for close work, and the other for distant
and driving. They all say that it can be quite functional. Nobody
mentioned color, but I'll ask.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Tue, 29 Nov 2016 20:34:42 -0800, Jeff Liebermann
wrote:

You can actually use a 128Kbit/sec sound card to hear (and see) the
60KHz signals. By implication, you can also see the nearby noise
sources. Buy a 128Kbit/sec sound card or dongle. Download a copy of
SDR Sharp. Go noise hunting. I'm sure you'll find something you
didn't expect.

Oops. That should be a 192KHz 24 bit sound card.
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 11/30/2016 07:45 AM, Jeff Liebermann wrote:
On Tue, 29 Nov 2016 22:30:26 -0800, "Stephen H. Fischer"
wrote:

In between the two eyes I had several weeks with one new and one old.
The colors were oh so much better with the new eye and remain so for both
eyes.
One thing about cataract sugary, do not delay it. Your eyesight may get
worse at an increasing faster rate, I was almost blind even with one good
eye as the old eye was so bad.

Thanks. I'm 68 solar revolutions old, so that's a real possibility.
No sign of cataracts, but I'm borderline with glaucoma.

High pressure, drops, no damage yet? Likewise. The main reason I had
my cataracts done was to get rid of the astigmatism (which glasses were
never able to fully correct and which made contacts very nearly
useless), and it worked really well!

Some of my
friends have had cataract surgery and opted for strange combinations,
such as one eye optimized for close work, and the other for distant
and driving. They all say that it can be quite functional.

I wouldn't dream of having permanent monovision (one eye for distance,
one for near), but I have contacts like that. The brain deals with it
-- mostly -- but there's a certain amount of ghosting unless the light
is really bright. My daughter doesn't even notice that with hers.

Nobody
mentioned color, but I'll ask.

Cataracts turn the lens yellow. I was really surprised to see the
difference in color between the two eyes. (I waited months to have the
second eye done -- I wanted to be SURE!) The brain makes everything
work together (my ski goggles are yellow, but within a minute or so the
snow is all white again; when I take the goggles off the snow is
slightly blue for a while), so it's not a real problem -- just interesting.

--
Cheers, Bev
"The object in life is not to be on the side of the
majority, but to be insane in such a useful way that
they can't commit you." -- Mark Edwards

One problem with multiple lens in each eyes is sun glint during the sunny
days and LED lights in dark rooms. After five years my mind is only
partially reducing that effect. Any bright spot on DTV with a black
background will have a halo.

I do NOT drive at night and do not recommend any one with multiple lens in
each eye to do so.

The 4th of July Fireworks is interesting, each spot of light is a little
Saturn with rings. All of them at once.

SHF

"The Real Bev" wrote in message
news
On 11/30/2016 07:45 AM, Jeff Liebermann wrote:
On Tue, 29 Nov 2016 22:30:26 -0800, "Stephen H. Fischer"
wrote:

In between the two eyes I had several weeks with one new and one old.
The colors were oh so much better with the new eye and remain so for both
eyes.
One thing about cataract sugary, do not delay it. Your eyesight may get
worse at an increasing faster rate, I was almost blind even with one good
eye as the old eye was so bad.

Thanks. I'm 68 solar revolutions old, so that's a real possibility.
No sign of cataracts, but I'm borderline with glaucoma.

High pressure, drops, no damage yet? Likewise. The main reason I had my
cataracts done was to get rid of the astigmatism (which glasses were never
able to fully correct and which made contacts very nearly useless), and it
worked really well!

Some of my
friends have had cataract surgery and opted for strange combinations,
such as one eye optimized for close work, and the other for distant
and driving. They all say that it can be quite functional.

I wouldn't dream of having permanent monovision (one eye for distance, one
for near), but I have contacts like that. The brain deals with it --
mostly -- but there's a certain amount of ghosting unless the light is
really bright. My daughter doesn't even notice that with hers.

Nobody
mentioned color, but I'll ask.

Cataracts turn the lens yellow. I was really surprised to see the
difference in color between the two eyes. (I waited months to have the
second eye done -- I wanted to be SURE!) The brain makes everything work
together (my ski goggles are yellow, but within a minute or so the snow is
all white again; when I take the goggles off the snow is slightly blue
for a while), so it's not a real problem -- just interesting.

--
Cheers, Bev
"The object in life is not to be on the side of the
majority, but to be insane in such a useful way that
they can't commit you." -- Mark Edwards

On 11/30/2016 10:10 AM, The Real Bev wrote:

I wouldn't dream of having permanent monovision (one eye for distance,
one for near), but I have contacts like that. The brain deals with it
-- mostly -- but there's a certain amount of ghosting unless the light
is really bright. My daughter doesn't even notice that with hers.

Don't you lose your binocular (3D) vision with that setup? I was offered
that for my implants but declined. I never really minded wearing glasses
all that much anyway. I have my implants set for indoor distances so
only really need glasses for reading and driving.

Cataracts turn the lens yellow. I was really surprised to see the
difference in color between the two eyes.

My color improvement was amazing. I had no idea I was that bad. When
they deteriorate slowly over the years you don't notice.

(I waited months to have the second eye done --

3 months for me. Between eyes I went to a Savers store and found some
used glasses that had a lenses that worked for the new eye and knocked
out the other lens for the old eye. Worked surprisingly well for that
time I had unbalanced eyes. Looked a little weird though.

I've had the implants in ten years now with no problems. My eyeglass
prescription never changes anymore which is nice. For some reason my
pupils now give a green reflection which gives my grandkids a charge.

For those contemplating the procedure my only advice is don't wait.

On 11/30/2016 09:20 PM, AL wrote:
On 11/30/2016 10:10 AM, The Real Bev wrote:

I wouldn't dream of having permanent monovision (one eye for distance,
one for near), but I have contacts like that. The brain deals with it
-- mostly -- but there's a certain amount of ghosting unless the light
is really bright. My daughter doesn't even notice that with hers.

Don't you lose your binocular (3D) vision with that setup? I was offered
that for my implants but declined. I never really minded wearing glasses
all that much anyway. I have my implants set for indoor distances so
only really need glasses for reading and driving.

Not that I've noticed. The out-of-focusness isn't that bad, especially
when my pupils are stopped down. I would never have selected monovision
IOLs, but I was surprised at how good the contacts are.

I had my IOLs set for distance. I spend most of my time doing close
stuff, but I want to be able to see without glasses outside, which seems
much more urgent. Besides, the 99-Cents-Only Store reading glasses work
just fine, but you have to pay to get prescription distance glasses!

When my mom had her cataracts done her ophthoquack decided she should
have near vision, which meant that she wore trifocals and hated them.
She was really angry when I found out and told her that she could have
chosen distance if that's what she wanted. The quack was a quack in
other ways too, and another ophthalmologist spent half an hour on the
phone trying to convince me not to report the ******* to the medical
board. He won -- I knew I wouldn't be able to get a doctor to testify
against the quack, but I was seriously thinking of picketing his office.
Mom didn't want me to, so I didn't. "Ask me how Dr. Schiff blinded my
mom..."

Cataracts turn the lens yellow. I was really surprised to see the
difference in color between the two eyes.

My color improvement was amazing. I had no idea I was that bad. When
they deteriorate slowly over the years you don't notice.

(I waited months to have the second eye done --

3 months for me. Between eyes I went to a Savers store and found some
used glasses that had a lenses that worked for the new eye and knocked
out the other lens for the old eye. Worked surprisingly well for that
time I had unbalanced eyes. Looked a little weird though.

I just had one lens in my regular glasses replaced. Did the other one
after the other eye was done. Glasses still improve my vision, but it's
just SOOO much better than it was that I'm not about to complain. Well,
maybe a little...

I've had the implants in ten years now with no problems. My eyeglass
prescription never changes anymore which is nice. For some reason my
pupils now give a green reflection which gives my grandkids a charge.

Slick.

For those contemplating the procedure my only advice is don't wait.

Or at least wait until insurance covers it.


--
Cheers, Bev
"The object in life is not to be on the side of the
majority, but to be insane in such a useful way that
they can't commit you." -- Mark Edwards

On 11/30/2016 10:51 PM, The Real Bev wrote:
On 11/30/2016 09:20 PM, AL wrote:

For those contemplating the procedure my only advice is don't wait.

Or at least wait until insurance covers it.

For sure. Mine cost me 50 bucks an eye.

On 11/30/2016 11:15 PM, AL wrote:
On 11/30/2016 10:51 PM, The Real Bev wrote:
On 11/30/2016 09:20 PM, AL wrote:

For those contemplating the procedure my only advice is don't wait.

Or at least wait until insurance covers it.

For sure. Mine cost me 50 bucks an eye.

Was that for 'normal' lenses or toric/multifocals? Medicare pays for
ordinary lenses, but the user has to pay the difference for the fancy
lenses. $1K each for torics and $3K each for toric multifocals.

--
Cheers, Bev
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^
"The language of victimization is infinitely extensible." -- Me

On 12/2/2016 1:01 PM, The Real Bev wrote:
On 11/30/2016 11:15 PM, AL wrote:
On 11/30/2016 10:51 PM, The Real Bev wrote:
On 11/30/2016 09:20 PM, AL wrote:

For those contemplating the procedure my only advice is don't
wait.

Or at least wait until insurance covers it.

For sure. Mine cost me 50 bucks an eye.

Was that for 'normal' lenses or toric/multifocals?

Normal lenses with UV and blue light filter.

Medicare pays for ordinary lenses, but the user has to pay the
difference for the fancy lenses. $1K each for torics and $3K each
for toric multifocals.

I'm on a Medicare Advantage (independent insurance company's) HMO plan
and the $50 was an outpatient co-pay per procedure. I was offered other
types of lenses at the time but it's been ten years and I don't remember
what they were or any added costs.