JI1FGX/DU9 Mindanao, Philippines Amateur Radio Diary IOTA OC-130
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Introduction. [Lily Diary]
Diary of Life in Mindanao

25/06/07  Introducing the Shack
25/06/06  A portrait illustrated 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 antennas
Stepping motor this and that
25/05/15 3.5MHz stepping motor plan
25/05/14 3.5MHz tuning coil installed
25/05/11 3.5MHz antenna installation completed
25/05/03 JTDX automatic operation 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 FTDX3000 LCD repair preparation
25/04/22 Installation plan for 3.5 MHz Twep antenna
25/04/21 AutoCWType_Ver1.1
25/04/20 10,14MHz antenna installation completed
25/04/19 JTDX automatic operation program Ver0.4.1
25/04/19 Antenna pole installation at 14 MHz
25/04/18 ThinkPad X390 repair completed
25/04/17 Search is now available.
25/04/15 Preparation of 10 MHz dipole
25/04/12 Hexbeam Part8
25/04/06 ThinkPad X390 is broken.
25/04/05 Time Setting Program
25/03/31 JTDX Automatic Operation Program
25/03/30 Automatic log sending from CWType to Hamlog
25/03/21 Hexbeam Part7
25/03/20 FreeDV Part3 First QSO
25/03/18 FreeDV Part2 QSO in shack
25/03/16 Hexbeam Part6
25/03/15 FreeDV Part1 installation
25/03/09 Hexbeam Part5
25/03/07 Hexbeam Part4
25/03/05 28MHz antenna modification
25/03/01 FTDX3000 is broken!
25/02/28 Pile up at 50MHz FT8
25/02/28 DXV500ZS linear amplifier repair
25/02/27 Pipe and rebuild plan for tower
25/02/26 Direction of Japan from Ozamiz
25/02/26 28MHz does not fly.
25/02/23 DXV500ZS linear amplifier repair
25/02/22 Hexbeam Part3
25/02/21 Hexbeam Part2
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 Antenna repair at 7,21 MHz
25/02/08 CW operation 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