By David, on November 18th, 2009%
I stumbled upon this page over at dxing.com and thought it to be a very cool and useful tool…rather than have a million color coded squares, just break up the low frequency, medium frequency and high frequency (HF) spectrum up into a number of bands and provide a high level explanation of what one may find there.
I’ve placed it here because, yes I think you will appreciate it, but mainly so I can refer back to it when I find myself tuning around the bands and hear myself self say “well I wonder what this is?” Bookmark this and you can do that, too!
150 kHz and below: . . .
To read the rest of this article, please click here: → Assignment of Radio Spectrum Understandably Explained
By David, on June 26th, 2009%
I just read this in the “ARLP026 Propagation de K7RA” from the ARRL and I found it quite interesting and thought it was quite worthy of sharing with you.
It was written by Red Haines, WO0W of La Crescent, Minnesota, USA.
“Though we use the sunspot number and the solar flux index to assess propagation expectations, there is only an indirect connection between these indices and propagation. Neither sunspots nor the radiation measured by the solar flux index directly increase or decrease the levels of ionization in the ionosphere. All three are determined, somewhat independently, by physical processes on or in the Sun.
“Sunspots and the solar flux are . . .
To read the rest of this article, please click here: → Sunspots Poor Predictors of Propagation
By David, on June 18th, 2009%
The decibel was originally used by the telephone companies to quantify audio signal gains and losses in telephone circuits. The original unit was named the “bel” after Alexander Graham Bell, who was the inventor of the telephone.
In most electronics work, however, the bel is too large a unit, so we use the decibel, which is one-tenth of a bel. It’s referred to as “dB.”
In radio, the decibel is the expression of the ratio between two signals. The signals might be voltages, currents or power levels.
The formula to compute the decibel using the ratio of 2 power levels is:
dB = 10 LOG (P1/P2)
Where . . .
To read the rest of this article, please click here: → Decibels in Amateur Radio
By David, on April 22nd, 2009%
Someone asked the question the other day, “what is a repeater?”
Funny, I always knew what a repeater was and so it never occurred to me that anyone might not know. I’m glad they asked; it gives me an opportunity to consider a question I had never considered before.
A repeater is basically a special type of Amateur Radio station that receives a signal on one frequency and retransmits the information carried on that signal on another signal at a different frequency.
A repeater is typically installed on some high point, such as atop a ridge on perhaps a tall building, so that it can be more easily reached . . .
To read the rest of this article, please click here: → What is a Repeater?
By David, on April 4th, 2009%
Iota stands for Islands On The Air. Amateur radio operators track nearly everything they do based on type or location or something. There are awards for working all the states in the US, working all continents on the planet, working countries, working counties, and others.
Well there are awards for working islands and the islands are given IOTA designators, for tracking purposes.
Below I have compiled a list of the IOTA designations for the islands in the Pacific Ocean, provided here for your reference (and mine since I live right in the middle of the Pacific!):
OC009 KC6 – Palau OC010 V63 – Pohnpei OC011 V63 – . . .
To read the rest of this article, please click here: → IOTA Designations for Islands in the Pacific
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