By David, on August 12th, 2010%
The Global Ionospheric World Map indicates the frequency in MHz at which a signal transmitted more or less straight up (about 70 – 90 degrees) will no longer bounce back to Earth, but rather escape out into space.
In short, this picture shows the Maximum Usable Frequency (MUF) for Near-Vertical Incident Skywave (NVIS) propagation.
NVIS is the mechanism for reliable HF communications within a region (500 mile radius). Without NVIS, there is a skip zone or dead zone where neither groundwave propagation nor skywave propagation are effective. This skip zone is often a band around the transmission site extending from between 20 miles (where groundwave leaves off) and . . .
To read the rest of this article, please click here: → Global Ionospheric World Map
By David, on August 9th, 2010%
Another off-topic post to the Elecraft reflector … sage advice on how to really learn CW. Too good to pass up, I wanted to capture it for my reference, and thought you’d like to see it too.
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As a long time high speed CW op, let me pass on an few of what I feel are the keys to learning to receive effortlessly at QRQ levels. The goal is to get to the point where listening to CW is exactly like listening to a conversation; that is, there is no conscious translation from dits and dahs into letters, words, and ultimately, phrases.
The first thing do to do . . .
To read the rest of this article, please click here: → Learning CW Tips
By David, on August 8th, 2010%
I follow the Elecraft email reflector — I find it to be a very good source of information. Yes, it’s mostly Elecraft equipment related, but every once in a while these guys go a little off-topic and manage to share some really good information of general interest.
Recently, such an off topic thread occurred. From it, a number of very good tips regarding CW operation came forth. One of the other reflector followers created this brief compilation. I’m including it here because I will no doubt refer to it many times in the future. Perhaps you’ll find it of value as well.
Enjoy!
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Hi All,
Below is a . . .
To read the rest of this article, please click here: → CW Tips Compilation
By David, on July 26th, 2010%
While AH6TD is fundamentally an Apple Macintosh station, I have been interested in an absolutely incredible piece of software, free software, called Ham Radio Deluxe. For the longest time, however, I have been unable to use the latest version, version 5, because it was astoundingly unstable. No more. Ham Radio Deluxe 5 is alive and well at AH6TD. . . .
To read the rest of this article, please click here: → Ham Radio Deluxe 5 Alive and Well at AH6TD
By David, on July 13th, 2010%
(Courtesy Wayne Burdick of Elecraft, Inc.)
The K3 provides a way to adjust speech controls and ALC level off-air.
(Technical note: The reason this is possible is that the K3's fast ALC
is established in the DSP. This means the K3's first-I.F. crystal
filters can be used in TX mode to ensure that dynamic ALC responses
are band-limited. This prevents the kind of splatter often heard from
rigs that apply fast ALC in hardware, after the crystal filter. This
technique also allows the DSP to provide very effective, very clean
speech . . .
To read the rest of this article, please click here: → Elecraft K3 Operating Tip: Using TX TEST to Adjust Speech Controls and ALC Level
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