Even better low-pass filters for transmitters, LA3ZA Blog

Even better low-pass filters for transmitters
LA3ZA Radio and Electronics Blog

http://la3za.blogspot.com/2016/11/even-better-low-pass-filters-for.html#more

Ly3LP, AO-91: Reverse double Lazy H

AO 91. Reverse double Lazy H

http://sa555.blogspot.com/2018/06/ao-91-reverse-double-lazy-h.html

ADIF Tools from NS6T

ADIF Tools from NS6T

Make a Contact Map from an ADIF File
Logbook of the World ADIF filter

https://ns6t.net/azimuth/adiftools.html

Software Defined Radio Academy, 2018 Videos

Software Defined Radio Academy

https://www.youtube.com/channel/UC1GAlgAQrkjeeLmIkCB8pgQ/videos

IOTA Challenge: Work all the XX-001 Islands

I enjoy island chasing and especially the RSGB's Islands on the Air (IOTA) program.
The QSL cards from the islands are often very nice. I use and like LOTW for electronic confirmations, but I almost always send off for a paper QSL too.

I wondered what it would take to work the first designated island in the IOTA designated geographic areas.

IOTA entities are organized into seven broad categories based on geography:
Africa: AF-xxx. AF-001, 3B6, Agalega Islands
Antarctica: AN-xxx. AN-001, Various prefixes, Graham Land West (Adelaid Island)
Asia: AS-xxx. AS-001, VU, Andaman Islands
Europe: EU-xxx. EU-001, SV5, Dodecanese
NA: NA-xxx. NA-001, C6 Great Bahamas Bank group
Oceania: OC-xxx, VK, Australia (Main Island Only)
South America: SA-xxx. SA-001, CE0, Easter Island
   xxx= specific island designation

I think most would agree, at least for continental USA staions, that NA-001, OC-001 and SA-001 would be the easiest to work. I admit I have a West Coast bias on this.

 EU-001 is harder to work but there seem to be stations to work although I do not have it confirmed for IOTA. I have worked it via remote station in CT but this can not, because of CT distance from my home QTH, can not be used in the IOTA program.

 AF-001 and AS-001 are more challenging in that their are fewer stations to contact. My impression is that AF-001 3B6 Agalega Islands and AS-001 VU Andaman Islands are mostly served by expeditions and are relatively rare. Nevertheless I have had heard these such stations over the last couple years. I do not have either confirmed for IOTA though.

 AN-001 is probably the most difficult to work because of the location and sparsity of stations. Not to mention the DX pileups such places create!

The specifics on AN-001 are:
  AN-001   Various Prefixes  ( 66º35–68º30S, 066º00–070º00W)
  ======================================
  d.GRAHAM  LAND  WEST  (ADELAIDE  ISLAND)  group  (=Adelaide  [Rothera  Base VP8],  Amiot  Isls, Detaille, Horseshoe, Kirkwood  Isls, Leonie  Isls  [include  Anchorage,  Lagoon,  Leonie], Liard, Stonington


I've concluded that the working all seven of the XX-001 IOTA island groups would be quite a challenge but would take some time given that DX expeditions or research stations would provide the best--or only--opportunity for two to three of the necessary QSOs.

Information on Working FM Amateur Radio Satellites

Some good information to Work FM Amateur Radio Satellites
Setting up your HT for popular sats and general tutorials.

http://www.work-sat.com/Home.html

Vertical Antennas, Radial Length and Number of Radials by Rudy Severns, N6LF

Here is a very good article written by Rudy Severns, N6LF.
http://www.antennasbyn6lf.com/files/radiation_resistance_variation_with_radial_system_design.pdf

It answers many questions hams have about vertical antennas and how the number of and length of radials influence the radation resistance of vertical antennas made for the 40 M band.

Ground resistance soil conditions are also taken into account and  discussed.

NEC models are used.