JI1FGX/DU9 Amateur Radio Diary, Mindanao, Philippines, IOTA OC-130.
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Yesterday's access.
Introduction. [Lily Diary.】
A diary of life in Mindanao.

   
25/07/13  IARU HF Contest
25/07/10 Software updates
25/07/08 DXV500ZS linear amplifier repair
25/07/07 CQ Machine Program
25/06/21 LoTW system upgrade
25/06/18 RG8 for 3.5MHz arrived
25/06/15  Time setting Ver0.5
25/06/14 Drone Habsan ZINO arrives
25/06/12 Philippine Independence Day
25/06/11 Algeria 7X2RF QSL card.
25/06/10 Translation API Program
25/06/09 DXCC150 award certificate arrived
25/06/08 AutoCWType_Ver1.4.1
25/06/07 Introducing the Shack
25/06/06 A portrait drawn by ChatGPT.
25/05/26 Windows full-width/half-width switching.
25/05/17 OK2ZAW BCD to 16 converter.
25/05/16 For 3.5MHz Zepp antenna.
Stepping motors
25/05/15 3.5MHz stepping motor design.
25/05/14 3.5MHz tuning coil installed.
25/05/11 3.5MHz antenna installation completed.
25/05/03 JTDX Autonomous Driving Program Ver0.4.3.
25/04/26 Drone Habsan ZINO.
25/04/25 Time setting Ver0.3.
25/04/24 AutoCWType_Ver1.3.
25/04/23 Preparing for FTDX3000 LCD repair.
25/04/22 Installation plan for 3.5MHz Zepp antenna.
25/04/21 AutoCWType_Ver1.1.
25/04/20 10,14MHz antenna installation completed.
25/04/19 JTDX Autonomous Driving Program Ver0.4.1.
25/04/19 14MHz antenna pole installed.
25/04/18 ThinkPad X390 repair completed.
25/04/17 Search is now possible.
25/04/15 Preparing the 10MHz dipole.
25/04/12 Hexbeam Part8.
25/04/06 My ThinkPad X390 is broken.
25/04/05. Time setting program.
25/03/31 JTDX Autonomous Driving Program.
25/03/30 Automatic log sending from CWType to Hamlog.
25/03/21 Hexbeam Part 7.
25/03/20 FreeDV Part 3 First QSO.
25/03/18 FreeDV Part 2 QSO in the shack.
25/03/16 Hexbeam Part 6.
25/03/15 Install FreeDV Part1.
25/03/09 Hexbeam Part5.
25/03/07 Hexbeam Part 4.
25/03/05 28MHz antenna modification
25/03/01 FTDX3000 is broken!
25/02/28 Pileup at 50MHz FT8.
25/02/28 DXV500ZS linear amplifier repair.
25/02/27 Tower pipe rebuilding plan.
25/02/26 Direction to Japan from Ozamiz.
25/02/26 28MHz is not available.
25/02/23 DXV500ZS linear amplifier repair.
25/02/22 Hexbeam Part 3
25/02/21 Hexbeam Part 2
25/02/18 28MHz antenna construction.
25/02/17 18,24MHz antenna height construction.
25/02/16 Z26NS Cosovo.
25/02/14 21MHz FT8
25/02/12 7,21MHz antenna repair.
25/02/08 Operating CW at 21MHz.
25/02/05 DXV500ZS linear amplifier failure.
25/01/19 Input Director.
25/01/14 Temporary license renewal.
28MHz does not fly (2025/02/26) 
Diary for February 18, 2025As I mentioned in the following article, I have raised a 28MHz dipole, but it does not fly very well.
I can see a number of European stations at -15 to -20 on FT8, but when I call them, they don't take it at all.
According to ChatGPT, the following is

�1. Propagation characteristics for Europe
Conditions are severe for 28 MHz and European propagation.
28 MHz requires F-layer propagation (for long distances), especially in Europe, where distances range from 8,000 to 10,000 km,
It is not reachable by E-spot and relies on the F2 layer.
Conditions in the ionosphere are more severe in the European region than in Asia and Oceania, so it is more difficult to reach these areas if conditions are not good.

in generalGray Line Propagationis famous for its low bands (1.8 MHz, 3.5 MHz, and 7 MHz),Also effective at 28MHz (10m band) This can be especially advantageous for long-distance communications to Europe.

28 MHz and gray line propagation

  • **Gray Line** is the boundary between day and night on Earth, and is the time of sunset and sunrise.
  • At this time of the day.Ionosphere (especially the F2 layer) is enhancedBecause of,long distance DX communicationIt is advantageous to

Why is Gray Line effective at 28 MHz?

  1. Ionosphere Enhancement:
    At sunset and sunrise, the F2 layer is more stable and the 28 MHz band is more reflective. Especially when solar activity is high, the gray line can be used toEurope, Africa, South AmericaIt is easier to reach to the

  2. Decreased absorption:
    Absorption in the D layer (low altitude ionosphere) is reduced, allowing the signal to travel farther. This phenomenon is especially useful for long distance propagation.


🟢 Measures:
**Aim for the time around sunset (gray line).
For Europe, the evening hours of 16:00-19:00 (PHT)** are particularly favorable.

Favorable gray line in Philippine time

  • Evening 16:00-19:00(around sunrise in Europe)
  • Early morning 05:00 - 07:00(Around sunset in Europe)

**Check the Solar Flux (Solar Activity Index)** and aim for days above 150, 28 MHz will be strong, especially toward Europe.
→ Check the latest data at Solar Data on QRZ.com.
Is this the limit of the inverted V of about 15 mH?
I am not sure if I should wait for Hexbame to be raised or build a 4EL yagi and see what happens.
I designed an antenna at MMANA with a handheld that does not fly.

I'm off to the glass/aluminum store to get a quote on materials.
 
 
 
　
Will this fly better than a dipole?
February 23, 2024   February 26, 2025