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May 11 2010

RFC Show Notes Episode 021

00:00 Opening Theme  
00:53 Introduction Not a regular podcast this time due to day job responsibilities. Instead, we have a “best of” episode featuring a couple of interviews from past episodes.

What do you think of the new opening music?

02:23 Interview (Repeated from Episode 7)
Carl, K9LA, propagation guru, president of the Fort Wayne, Indiana DX Association, DXCC Honor Roll, 5 band DXCC, and author of many articles. Carl will discuss radio wave propagation. For hams, ionospheric propagation is the most significant. Electro-magnetic waves can travel in a straight line, or be refracted (bent) by the ionosphere. The lower the frequency, the more the radio waves are refracted.
07:45   Space weather refers to the impact the sun has on our planet. In the extreme, solar flares can cause disruptions to satellites, the power grids, and pose health hazards to astronauts.
10:07   K-Index: a measure of the activity of the earth's magnetic field. A solar hiccup can distort the earth's magnetic field. The K-index is a logrithmic three-hour index, from 0 (quiet) to 9 (most disturbed). As amateurs, we would like the K-index to be small.
12:33   A-Index: derived from the K-index, an average of the eight, three-hour K-index values, reported on a linear scale from 0 (quiet) to 400 (most disturbed).
13:58   Geomagnetic storms: the major disturbance to propagation caused by a Coronal Mass Ejection (CME). Can produce aurorae. Can induce currents in power grids that can cause blackouts. Can last for several days.
16:37   Solar flares. Emits lots of x-ray radiation, which increases d-region absorption on the sunlit side of the earth, lasting an hour or two. A solar flare can also emit relativistic protons, again causing increased d-region absorption over the poles. More information can be found at the Space Environment Center web site.
19:17   Sunspots: areas on the sun associated will extreme ultraviolet radiation which causes the formation of our ionosphere. More sunspots increases the density of the ionosphere, which increases it's ability to refract the higher frequencies, like 10, 15 and 20 meters.
21:08   Where can we find realtime information? Listen to the 10MHz WWV at 18 minutes past the hour, which will give the current K-index, yesterday's A-index, and the solar flux (sunspot number). Also on the web: SEC web site, spaceweather.com, www.dxlc.com/solar, dx.qsl.net/propagation.
24:44   There are also computer propagation pgms: ioncap, voacap (free download), w6elprop, hfprop (replaced by voaprop -Ed.). Search for “hf propagation program” for many more. They all basically use the same ionospheric model.
28:12   Propagation modes: sporadic E or E-skip: there are three regions, D, E, and F. During a summer day, “clouds” of E region density can form allowing great skip distances.
32:44   Auroral propagation: When the geomagnetic field becomes disturbed, the electron density becomes high enough to reflect radio waves, particularly at 6 meters and higher frequencies. Happens when the K-index is high.
38:23   Blind zone, or skip zone.
40:35   NVIS (Near-vertical incident skywave)
41:15   Closing comments.

References:

  • “The New Shortwave Propagation Handbook” by CQ Propagation Editor George Jacobs, W3ASK, Ted Cohen, N4XX, and Robert Rose, K6GKU. available from the CQ Magazine store and from Amazon.
  • “The Little Pistol's Guide to HF Propagation” by Bob Brown, NM7M. Unfortunately, it is out of print, but is available on the Worldradio 2000 Archive CD. (Ed. note: the URL given in the podcast, www dot wr6wr dot com, no longer works.)
  • You may reach Carl at K9LA@arrl.net.
45:49 Song “Sunrise Blues” by Samuel James from the album “Songs Famed for Sorrow and Joy”
46:30 Interview (Repeated from Episode 5)
Roy Rabey, AD5KZ, former ARRL section manager for the north Texas section and repeater guru discusses the ins and outs of repeaters.
47:28   What is a repeater?
50:30   What does the repeater controller do?
56:16   Repeater linking, Echolink and IRLP.
59:28   Can anyone set up a repeater?
1:03:55   What is a repeater trustee?
1:08:14   Is the trustee the same thing as the control operator?
1:11:00   What repeater equipment does Roy have running?
1:17:24   Closing comments.
1:19:45 Conclusion Email Richard at kb5jbv@gmail.com

Twitter: twitter.com/kb5jbv

KB5JBV on D-Star via port C on the NE5R repeater.

Opening theme music is “Give It All Away”, by midliFeCrisis, from the album “Live from the Loft” available at http://www.podsafeaudio.com

Closing theme music is “We Gotta Go” by David Henderson at Podsafe Audio.

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