1. Understand band condition information Use a propagation gadget
PROPAGATION & GADGETS
Understand band condition information Use a propagation gadget
By:
Dick Morgan K6RAH

2. Radio Signal Confusion? Yes!
Like predicting the weather…only harder!
Whole branch of science – complex & evolving
Changing space weather conditions affect all hams
Solar cycles
Seasonal variations affecting frequencies differently
Radio blackouts (X-Rays)
Solar radiation storms (Proton flux)
Geomagnetic storms (A & K-Index, solar wind, Bz)
Solar flux & Sunspot number
Electron flux (Electron flux)
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

3. What’s To Know? Solar activity tends to go in 10 to 11 year “cycles”
Now well into Solar Cycle 24
Cycle 19 was an historic era for ham radio
Many factors affect electromagnetic radio waves
Sun generates most factors via ultraviolet radiation
The factors affect the ionospheric layers above Earth
Some happen simultaneously – good & bad
Solar flares, solar winds, X-rays, Coronal Mass Ejections, and sunspots
MUF = Maximum Usable Frequency changes
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

4. The Ionosphere Outer part of Earth’s atmosphere Several layers
High electron & ion content
Constantly changing
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

5. What’s To Know? The Ionosphere 30 to 300+ miles above Earth
Often described in four distinct layers
D = closest to Earth miles up (daylight hours only)
E = miles up (mostly daylight only)
F1 = miles up
F2 = 250+ miles up
Layers can absorb, reflect, or pass radio waves
Ionospheric conditions affect frequencies differently
Frequencies differ between day and night
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

6. Transmission Modes Line of sight (VHF & UHF) - Repeaters
Ground Wave – Lower frequencies
Refractions/Skip – Important for HF DX
Special Effects –Scatter; Ducting; Sporadic E, Earth-Moon-Earth, etc.
No signal in Tulsa?
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

7. Gadgets Provide a Summary
HF Conditions by band
VHF Conditions
Detailed propagation readings
Visual of the Sun – yes/no
Sunspot Number
Solar Flare Index
Maximum usable frequency (MUF)
Available on QRZ.com & K5RWK.org
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

8. SFI = Solar Flare Index Solar radiation @10.7cm (62.5 to 300 scale)
Indicates “F layer” ionization level
Higher number means more ionization = DX!
High number increases the MUF
Updated 3 times daily
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

9. SN = Sunspot Number Scale is 0 to 250. Calculated & updated once daily
Loosely correlates to the solar flare index
Higher sunspot numbers = usually better DX
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

10. A = Planetary A Index
Scale is 0 to 400. Calculated & updated once daily
Measures average geomagnetic activity
Lower number = usually better DX (below 15)
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

11. K = Planetary K Index Scale is 0 to 9. Calculated & updated 8X daily
Measures geomagnetic activity
Lower number = usually better DX (below 5)
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

12. Hard X-Rays
Scale is A0, B, C, M, & X9.9. Calculated & updated 8X daily
Measures intensity X-Rays mostly impacting D Layer
A & B levels = better propagation
C levels up = higher signal absorption, poor conditions
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

13. 304A = 304 Angstroms Scale is Zero to Unknown. Updated hourly
Measures total angstroms
Makes up about half of all F Layer ionization
Correlates loosely to the Solar Flare Index
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

14. Proton Flux Scale is Zero to Unknown. Updated hourly
Measures density of charged protons in the solar wind
Higher numbers mean greater impact on E Layer
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

15. Electron Flux Scale is Zero to Unknown. Updated hourly
Measures density of charged electrons in solar wind.
Higher numbers mean greater impact on E Layer
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

16. Aurora Scale is Zero to 10++. Updated hourly
Measures strength of F Layer ionization in polar regions.
Higher numbers mean greater lower latitude
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

17. N = Normalization Scale is Zero to 5. Updated hourly
Measures confidence in Aurora measurements.
Lower numbers mean greater confidence
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

18. Bz = Bz Component Scale is +50 to -50. Updated hourly
Measures strength and direction of the interplanetary magnetic field as impacted by solar activity.
Positive = Same direction as Earth’s magnetic field Negative = Cancels Earth’s magnetic field. Increases impact of solar particles on ionosphere.
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.

19. Meaning for Us Hams?
Elements sometime work together, other times oppose each other. One measure does not tell the story! Listening is key!
The W0NBH Solar Gadget provides the facts, then interprets likely overall result on HF band conditions.
MUF, magnetic field, and basic noise level also very helpful.
Watch MUF increase as ionosphere becomes more & more active!
Gadget is on the QRZ.com & K5RWK home page.
Website is
Copyright The Richardson Wireless Klub, Inc. and Richard Morgan K6RAH.