Albert Einstein |
October 31, 2014
Difficulties in mathematics...
Do not worry about your difficulties in Mathematics. I can assure you mine are still greater. — Albert Einstein
October 25, 2014
Massive solar flare disrupts worldwide HF radio communication
Hams worldwide were having a great time today in the CQ WW SSB Contest (2014.10.25) on HF until about 17:00 UTC when a massive X-class solar flare caused radio blackout worldwide. The sound of all the HF bands closing down was remarkable. The only HF communication remaining active was via ground wave propagation. The HF radio blackout started to lift about 18:30 UTC with the re-opening of the 10m and 12m bands and then the other bands over time.
So what does X3.1 solar flare mean? Solar flares are classified as A, B, C, M or X according to the peak flux in watts per square meter (W/m2) X-rays near Earth, as measured on the GOES spacecraft.
Within each class there is a linear scale from 1 to 9.n (apart from X), so an X2 flare is twice as powerful as an X1 flare, and is four times more powerful than an M5 flare. X class flares up to X28 have been recorded.
Good DX and 73, NJ2X
X-class solar flare erupting 2014.10.25 Photo by NASA/SDO |
Massive X3.1 Class Solar Flare 2014.10.24 Photo by NASA/SDO |
So what does X3.1 solar flare mean? Solar flares are classified as A, B, C, M or X according to the peak flux in watts per square meter (W/m2) X-rays near Earth, as measured on the GOES spacecraft.
Classification | Peak Flux Range picometre (W/m2) |
---|---|
A | < 10−7 |
B | 10−7 - 10−6 |
C | 10−6 - 10−5 |
M | 10−5 - 10−4 |
X | 10−4 - 10−3 |
Z | > 10−3 |
Good DX and 73, NJ2X
October 24, 2014
Inventions have been the product of experiment and work based on physical reasoning...
Anyone who has had actual contact with the making of the inventions that built the radio art knows that these inventions have been the product of experiment and work based on physical reasoning, rather than on the mathematicians' calculations and formulae. Precisely the opposite impression is obtained from many of our present day text books and publications. — Edwin Armstrong
Edwin H. Armstrong |
Edwin H. Armstrong invented the regenerative circuit, superheterodyne circuit, superregenerative circuit, and FM radio.
October 17, 2014
Simplicibus...
October 12, 2014
Phonetic Alphabet Viewer iPhone app for learning the international phonetic alphabet
There seems to be an app for nearly everything. Are you working on learning the international phonetic alphabet? Well it turns out there is an app for that too - the Phonetic Alphabet Viewer available on the iPhone. This is a very simple app that provides the student with an interactive visual method of learning. Simply touch a key to see the phonetic equivalent spelled on the screen instantly. The price is right too - FREE. The app also has solid customer ratings which is often a good indicator of product quality.
Go through the alphabet in sequence saying the phonetic equivalent in your head. Then press the letter to check if you have it correct. When you find a letter that you struggle with pause for a moment to repeat the phonetic three times while focusing on the word.
You will be speaking the international phonetic alphabet in no time. Practice, practice, practice, ...
Good DX and 73,
NJ2X (November Juliet Two X-Ray)
Go through the alphabet in sequence saying the phonetic equivalent in your head. Then press the letter to check if you have it correct. When you find a letter that you struggle with pause for a moment to repeat the phonetic three times while focusing on the word.
You will be speaking the international phonetic alphabet in no time. Practice, practice, practice, ...
Good DX and 73,
NJ2X (November Juliet Two X-Ray)
October 10, 2014
Light consists in the transverse undulations...
We can scarcely avoid the inference that light consists in the transverse undulations of the same medium which is the cause of electric and magnetic phenomena. — James Clerk Maxwell
October 3, 2014
2014 California QSO Party
The California QSO Party
1600 UTC October 4, 2014 to 2200 UTC October 5, 2014
Please see http://cqp.org/ for all the rules and details. Hope to work you during the event.
From California, Good DX and 73, NJ2X
The first baby monitor
October 7-8, 2014, the Draconids
Be sure to take a look at the night sky. The Draconids meteor show will return to visit October 7-9, 2014.
Good DX and 73, NJ2X
Good DX and 73, NJ2X
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