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Copyright 2000-2021 R. C. Mazur, VA3ROM.
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30 June 2022
Added supporting material for my next TCA column "Radio Science: VLF Part 2 (RM055) plus supplementary articles to the Radio Magic page.
24 June 2022
Am in the middle of major home repairs & renovations so all my antennas & radios are off air for a few weeks. Not much fun living in a construction zone but I've put off things for far to long.
On the plus side, I'm clearing & throwing out a lot of "stuff" that I have no idea why I've stockpiled inside the house & never used. Plus I get to redesign my radio shack layout because 30 years after everything was first installed, I just can't remember why some things were done the way they were done during the reverse breakdown of my station!  
30 April 2022
Added supporting material for my next TCA column "Radio Science: VLF Part 1 (RM054) plus supplementary articles to the Radio Magic page.
07 February 2022
Added supporting material for my nextTCA column "FM Voice & Data & the ISS: Part 2" (RM053) to the Radio Magic page.
Windows 11 proved to be such a pain when I upgraded my only one desktop that met all the qualifactions that I quickly downgraded back because older programs crashed, common menu commands and functions were moved around just for the sake of "newness" and "improvement", which just slowed me down to a virtual crawl. Because I have perfectly working W10, W7 and even XP machines that can't be upgraded, I saw no point to keep W11 for the sake of the one. Unfortunately, all new Windows computers will be crippled by W11, and trying to switch back and forth between it and W10 will really drive you crazy! Can't imagine the hard choices that companies with tens or hundreds of W10 machines that can't be upgrade to W11 will face by 2025 when W10 support is ended. Spend thousands, tens of thousands or more dollars for no good reason other than to enrich Microsoft. And therein lies the rub when we let any one company have an 80% global operating system monopoly.
23 November 2021
Finally got around to reedditing and adding my past TCA articles "ISM Band HiFER Beacons: Part 3" (RM048), "Tinker Tailor Circuit CAD" (RM049) and "In the Year 2012..." (RM050) to the Radio Magic page.
31 October 2021
Well it appears that the "curse" of the odd numbered Windows OS is alive & well. New computers come with Windows 11 & new headaches. Why on earth the Microsoft programmers put the most commonly used mouse right-click commands (like cut, copy, paste, et al) in a second sub-menu is bizarre! Many older Windows 10 computers will not be able to upgrade (thankfully or fortunately) because of obtuse system requirements. Not as bad as Vista but not as good as the hype makes it out to be.
30 October 2021
Added supporting material for my next TCA column "FM Voice & Data & the ISS: Part 1" (RM052) to theRadio Magic page.
Put my new ZackTek WSPR Desktop transmitter & 7-28 MHz end-fed dipole (40, 20, 15 and 10 m) into operation, but the antenna also works well on the 17 & 12 m bands, too! The transmitter is easily programmed with the supplied software & can frequency hop across all the WSPR band segments, depending on the ZackTek version you buy. I added an attenuator pad to reduce RF power from 23 dBm to 10 dBm. Also did some tests with my TinySA & the WSPR Desktop's built-in LPFs do an excellent job of harmonic suppression.
The end-fed dipole has elongated high frequency side-lobes (meaning gain) that give my signal a boost from 20 m to 10 m. Its internal 64:1 impedance transformer probably explains its flatter VSWR high frequency response & higher efficiency over the lower turns ratio transformers typically used. Only on 30 m is the VSWR a tad too high (4:1).
30 September 2021
Just watched History Channel's "The Machines that Built America, S:1, Ep:7 Tesla vs. Marconi". Last year, I wrote a three-part article about their epic wireless "battle". I knew Marconi stole from others without giving credit or paying royalties, but what I learned from the TV show was that Sir William Preece, head of the British Postal Service, which controlled all forms of communications in Britain, had met with Nikola Tesla who foolishly revealed the secrets of his "Tesla coil"!
Shortly afterwards, Preece met with the young & ambitious Guglielmo Marconi who convinced Preece that a lot of money could be made from wireless telegraphy messaging between shore and ships at sea. But his limited transmitting range was a stumbling block & he needed money to build a much more powerful transmitter than he had. So Preece gave Marconi the information on the Tesla coil plus the financal support because he (Preece) thought that he could take advantage of the young Guglielmo. But Marconi was no business fool (like Tesla was) & quickly discarded Preece once he no longer needed his help. And the rest is history.
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