CadSoft EAGLE
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Remeber back on March 14th when I promised to review CadSoft's EAGLE program? Well,
I haven't forgotten. I downloaded it and started thru the documentation....then a bunch of
unrelated interruptions took place. So, please bear with me. I haven't forgotten!
On the other hand, if you've used the program and want to send me your review, I'll publish it
here on The Ham Weblog.
Well, lo and behold...there's another similar program worthy of mention:
IVEX Design International.
Like CadSoft, IVEX Design also has a demo version which you can download from their site.
However, I'm not quite certain whether you can get the same level of free functionality
here. The site does ask for considerable info, but there is a Hobbyist category
included.
Oh, here are the downloadable components (so maybe you actually can get more here):
· WinDraft (ver. 3.10) Schematic Design
· WinBoard (ver. 2.25) PCB Layout
· Ivex Spice (ver. 3.02) Simulation
Each component has its own downloadable manual as well.
For a well-written summary of this program, see "Math's Notes," CQ
Magazine, February 2001, p.46.
Same goes for this suite of software. If you've used the program and want
to send me your review, I'll publish it here.
ToC
An Introduction to Differential GPS
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Well, we've all heard a lot about GPS, those geosynchronous positioning satellites.
But what's this about Differential GPS? As we'd heard, our DOD introduced a deliberate
error [selective availability they called it] into the public GPS system for
secruity purposes. So, for our use, the best we could hope for in accuracy, or
resolution, was about 80 meters.
According to Chris Halsall of O'Reilly Network, we can do better than that; but, we'll
have to do our homework and expend some energy and $$ to accomplish our goal. Basically,
we have to combine our portable GPS receiver input info with known locations. These
receivers then generate a differential, or error value, which they transmit to allow us
to determine our QTH with accuracy approaching that of the military or aviation receivers.
Check out Halsall's article. It's complete with figures depicting plots from typical
GPS receivers we might use, along with demonstrated plots which show how range errors
can be minimized. If you're into locating, this is a must-read! Just a brief addendum:
I talked to an engineer the other evening and he tells me that using Differential
GPS and just one fixed GPS receiver, you can accomplish millimeter accuracy. Now,
that's accurate!!
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ToC
What time is it? Well, you can check your watch, or you can tune in your favorite radio or
TV station and you might get the correct time. Or you can check
WWV.
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Well, I've checked this site three times, and the last two, I've experienced a machine lock-up
each time, so be warned!! I don't know why; just that it's happened. And, a few weeks ago, I
experienced an identical problem with another ".gov" page--that time it was an FCC page. Don't
know what our government's up to, but......... I guess I should note that my lock-up this time
was not on the actual "time" page, but rather on the page that explains about the National
Bureau of Standards site. Any ideas as to what might cause this???
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ToC
Here's a ham radio site in the news: ARISS.
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This site is available in French and English.
ARISS is up and running. to be manned by USA, Russia, Japan, Europe and Canada. This page
has lots of information; however, as we seem to be in a current mission, the data on "latest
news" with regard to the ISS Shuttle Launch schedule seems just outdated: According to
this page, Space Shuttle Endeavour was to launch from Kennedy Space Center on April 19. A
small glitch, to be sure, as I'm certain that NASA folks are pretty busy with mission tasks
at present, not updating this particular page.
Other pages on the ARISS site include:
There is so much information at the ARISS site that you could probably spend
days to read it all! We've just skimmed the surface here, so jump on over there
and look for yourself.
ToC
"Tis the season! Spring means storms, so here's
The
National Weather Service.
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K3DZ sent this our way....Tnx, Frank! Locate your point of interest and
click the mouse. This is a really neat page! And, as close to real-time
as is probably possible. As I'm writing this, it's 19:33 hrs [EDT]. And,
I just set my watch at WWV a couple of hours ago (above)! The page lists
19:27 hrs. So, you can probably count on current data here.
You can check adjacent radars as well. Just click on the arrows to the
left of the map display. Just to check whether the system makes adjustments
for geography with this feature, I punched up the upper-most dot in northern
California: Eureka, CA. And, the adjacent radar box changes, showing
no adjacent radars west of Eureka. Well, I guess not; Eureka is on the coast!
Click the "Loop" button to see any WX tracking across the area of interest.
This is neat stuff...Tnx agn, Frank!!! I could sit here and play all day, Hi!!
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ToC
Well, that wraps it up for today. Please, drop me an email and let me know what
you think about The Ham Weblog, ok? Also, I'm always open to ideas and suggestions
for other content to publish on this site. What do you want to read about? It's easy; just
Email K3LBP!
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