Amateur Radio Propagation Studies


Science, research, engineering, operating


Section 1

Section 2

Section 3

Section 4

Section 5

Section 6


Thunderstorm effects

Aurora & FAI

Tropospheric ducting





Multiple hop on VHF

Incoherent scatter

VHF transatlantic

Meteor scatter

Long-delayed echoes

Thoughts & discussions

This web site's highlights

Sporadic E


Radio astronomy


Multiple-tone effect

In this section you wil find all articles and papers in chronological order including the guest articles published on this web site. Reviewing my articles from ten or twenty years ago, I am very often not happy with my early work but I have to account for it, obviously. You may wonder what is the motivation of writing that many articles dealing with amateur radio propagation studies? First of all, I am fascinated about atmospheric physics, the radio sciences and many (not all) aspects of amateur radio and all this subjects may be combined in amateur radio propagation studies more or less perfectly. Second: writing a paper forces me to put my understanding in words and this process either leads to alternative ideas or it reveals an existing lack of knowledge and insight which needs to be addressed. The BeamFinder analysis software has finally pushed my personal activies in amateur radio propagation studies considerably, i.e. many articles, papers and documents actually result from analyses supported by the software (see the BFLogotiny4a-icon which indicates articles referring to the BeamFinder analysis software).


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Missing references?

Please contact the author if you find your publications and articles are not acknowledged properly in the papers.

The BeamFinder Logo

Articles displaying the BFLogotiny2a-logo indicate analyses using the BeamFinder software. In this documents, the BeamFinder user may find useful applications and information on the software's usage.


Unless otherwise stated, all material is copyright of Volker Grassmann. All rights reserved. The material, or parts thereof, may not be reproduced in any form without prior written permission of the author.

Guest article
VHF and microwave propagation - characteristics of ducts
Martin, A. L. (VK3KAQ)
January 2007
SpecialTopics1b3a1a3 English, PDF, 1.7 MB)
Use of satellite and aerial images to analyse double hop sporadic E radio links
Dubus 4, p. 67-88, 2006
SpecialTopics1c1b (English, PDF, 1.6 MB) - note the correction which is explained here
Open letter to the chairman and to the chief executive of the Particle Physics and Astronomy Research Council (PPARC)
May 2006
SpecialTopics1b1a1c1c (English, HTML, 44 KB)
Outcry of British scientists, closure of the UK ionosondes
April 2006
SpecialTopics1b1a1c3 (English, HTML, 20 KB)
NAVSPASUR radar experiments
April 2006
SpecialTopics1b3a1 (English, HTML, 100 KB
Improving vacuum tubes using pseudorandom symmetries
Part 1 (introduction)
Bode F. (DF1DM)
Schreiber U. (DF1DM)
Grassmann V. (DF5AI)
April 2006
SpecialTopics1b1b1d1a1a2 (English, PDF, 100 KB)
Improving vacuum tubes using pseudorandom symmetries
Part 2 (discussion of results)
Grassmann V. (DF5AI)
April 2006
SpecialTopics1b1b1d1a1a1a (English, HTML, 100 KB)
Hadley Cell Propagation - Discussion of results
March 2006
SpecialTopics1b3a1a1a (BFLogotiny2a1a1a, English, HTML, 100 KB)
Hadley Cell Propagation - Analysing systematical features in tropospheric dx QSOs between 144 MHz and 5.8 GHz exceeding the distance of 3.000 kilometers
February 2006
SpecialTopics1b3a1a1 (BFLogotiny2a1a1, English, PDF, 1.3 MB)
Dubus 1, 55-73, 2006 (the above article presented in the Dubus format)
SpecialTopics1b3a1a2 (BFLogotiny2a1a2, English, PDF, 1.7 MB)
Spotting large arrays @ Google Earth
December 2005, last update January 2006
SpecialTopics1b1b1d1 (English, HTML, 676 KB)
Raising the treasure of dx cluster data
Summary of the dxers' discussion in the email reflectors
December 2005
SpecialTopics1b1c1 (English, HTML, embedded in the below DXC article)
Guest article:
Predicting propagation on 2 & 6 meters
Gyde, B., ZL3NE/1
November 2005
SpecialTopics1b1b1d1a1a (English, PDF, 2.4 MB)
144 MHz long distance radio propagation from western Europe into the Atlantic Ocean, analysis of tropospheric inversion layers and the atmospheric refraction index along radiowave propagation paths exceeding 3700 kilometers
November 2005
SpecialTopics1b3c (BFLogotiny2c, English, HTML, 352 KB)
Meteors in the sky
August 2005
SpecialTopics1d1a2a (English, HTML, editorial)
a. More hints on thunderstorm effects on sporadic E
b. Neue Hinweise auf Gewittereinflüsse auf die sporadische E-Schicht
Dubus 3, p. 45-48, 2005
SpecialTopics1d1a1a (English/German, PDF, 212 KB)
The signature of the March 31, 2001 geomagnetic storm in Aurora dx communication on very high frequencies
last update June 2005
SpecialTopics1b2 (BFLogotiny4, English, HTML, 868 KB)
Thunderstom effects on mid-latitude sporadic E?
First results of a data analysis project in amateur radio
Grassmann, V., DF5AI
Cremer, S., DL1DBC
CAL Mid-term Review and Science Meeting,
Elounda, Crete, Greece, June 20-24, 2005
SpecialTopics1d1a1 (English, PowerPoint, 1.3 MB, including an animation of the June 27, 2004 event)
Thunderstorm effects on the ionosphere,
discussion of results and the readers' feedback
June 2005 (last update)
SpecialTopics1d1a (English, HTML, 2.1 MB including additional papers)
Geographical distribution of sporadic E and sferics on June 27, 2004
Grassmann, V., DF5AI
Cremer, S., DL1DBC
May 2005
SpecialTopics1d1a2 (English, GIF animation, 304 KB)
a. Thunderstorm effects on the F region of the ionosphere
b. Gewittereinflüsse auf die ionosphärische F-Region
Dubus 2, p. 58-61, 2005
SpecialTopics1d1b (English/German, PDF, 232 KB)
Thunderstorm effects on sporadic E propagation in 144 MHz (version 2)
April 2005
SpecialTopics1d1c (English, PDF, coloured and extended version, 1.3 MB)
a. Thunderstorm effects on sporadic E propagation in 144 MHz
b. Gewittereinflüsse auf die Sporadisch-E Ausbreitung im 144 MHz Band
Grassmann, V., DF5AI
Cremer, S., DL1DBC
Langenohl, U., DK5YA
Munters, A., PE1NWL
Sampol, G., EA6VQ
Kraft, J., DL8HCZ
Dubus 1, p. 9-44, 2005
SpecialTopics1d2 (English/German, b/w version, PDF, 1.2 MB)
Radar echoes from the sun
April 2005
SpecialTopics1b1b1a1a (English, HTML, editorial)
Discussing the future of ham radio
April 2005
SpecialTopics1b1b1d (English, HTML, editorial)
Airlifted VHF DXpeditions (AVDX)
April 2005
SpecialTopics1b1b1c (English, HTML, 212 KB)
Can radio amateurs do something similar?
April 2005
SpecialTopics1b1b1a1 (English, HTML, editorial)
Thunderstorm effects on sporadic E propagation in 144 MHz (v2)
Update of the below article, additional information, coloured images
April 2005
SpecialTopics1d1 (English, PDF, 1.3 MB)
What are you doing on August 12, 2028?
February 2005
SpecialTopics1b1b1a (English, HTML, editorial)
Aurora and FAI analysis software
February 2005
SpecialTopics1b1b1b (English, HTML, editorial)
Notes on the scatter properties of the lunar surface at radio wavelengths - the scattering area in moonbounce communication
June 2004
SpecialTopics1b3b (English, HTML, 696 KB)
Guest article:
144 MHz transatlantic propagation considerations
Obenhofer, W., NQ2O
August 2004
SpecialTopics1b1b1d1a1 (English, PDF, 60 KB)
Guest article:
Comparisons between Europe and North America
Obenhofer, W., NQ2O
July 2004
SpecialTopics1b1b1d1a (English, PDF, 64 KB)
Guest article:
Radio propagation studies using radio beacons in 2004 and going forward
Kayser, L., VA3LK
July 2004
SpecialTopics1b1b1d1a2 (English, PDF, 48 KB)
There are good reasons for ham web sites and amateur radio magazines to cooperate ... but how?
June 2004
SpecialTopics1b1b3 (English, HTML, editorial)
Spam messages disturbing the dx cluster spot lists
May 2004
SpecialTopics1b1b2 (English, HTML, 104 KB)
A remarkable short distance Aurora QSO ... interpreted by long distance field-aligned backscatter
May 2004
SpecialTopics1b3a (BFLogotiny15, English, HTML, 388 KB)
The Brendan trophies
April 2004
SpecialTopics1b1b2a (English, HTML, editorial)
FAI on the edge, Northern Italy to Crete
Dubus 1, p. 66, 2004
SpecialTopics1b1a1b2 (BFLogotiny14, English, PDF, 44 KB)
Geomagnetic storm from October/November 2003
D and E region ionization measured by the EISCAT Svalbard radar
December 2003
SpecialTopics1b1a1c1a (English, HTML, editorial)
Northern lights over Athens (November 20, 2003)
December 2003
SpecialTopics1b1a1c1 (English, HTML, editorial)
Spam Protected Email Addresses (SPEA)
December 2003
SpecialTopics1b2a1 (English, HTML, 110 KB)
FAI on the edge, Southern France to Madeira
Dubus 4, p. 70, 2003
SpecialTopics1b1a1b1c (BFLogotiny13, English, PDF, 44 KB)
a. Dx opportunities in 144 MHz double hop sporadic E - Ground reflection of radiowaves by lakes and rivers
b. Dx-Möglichkeiten bei 144 MHz "Double Hop" Sporadisch-E-Verbindungen - Reflexion von Radiowellen durch Binnenseen und Flüsse
Dubus, 4, p. 66-69, 2003
SpecialTopics1c1a (BFLogotiny2, English/German, PDF, 664 KB)
Very long distance propagation in the 144 MHz band
Part 2: Dx opportunities in the European sector
October 2003
SpecialTopics1c (BFLogotiny1, English, PDF, 732 KB)
VO1ZA - new 144 MHz transatlantic beacon
October 2003
SpecialTopics1b1a1c (English, HTML, editorial)
The Space Weather Multimedia CD ROM
Discover the nature of solar-terrestrial phenomena
August 2003
SpecialTopics1b2a (English, HTML, 204 KB)
Very long distance propagation in the 144 MHz band
Discussion of the May 20, 2003 dx opening
Readers' comments, feedback, contributions
Grassmann, V., DF5AI
Langenohl, U., DK5YA
August-October, 2003
SpecialTopics1a (English, HTML, 36 KB)
Very long distance propagation in the 144 MHz band
Discussion of the May 20, 2003 dx opening
Grassmann, V., DF5AI
Langenohl, U., DK5YA
July 2003
SpecialTopics1 (BFLogotiny, English, PDF, 2.5 MB)
The scientific method in ham radio
July, 2003
SpecialTopics1b1a1d (English, HTML, 48 KB)
FAI on the edge, Austria to Balearic Islands
Dubus 2, p. 74, 2003
SpecialTopics1b1a1b1 (BFLogotiny12, English, PDF, 44 KB)
Transatlantic transmission on 144 MHz
VHF Communications, 2, 2003, p. 84-89
Translation and PDF courtesy of the VHF Communications Magazine.
SpecialTopics1b2b (BFLogotiny1b, English, PDF, 180 KB)
Doppler effect in Auroral backscatter - discussion of results
April, 2003
SpecialTopics1b1a1a (English, HTML, 116 KB)
Doppler effect in Auroral backscatter
February 2003
SpecialTopics1b1a1 (BFLogotiny10, English, PDF, 408 KB)
Auroral backscatter with unequal propagation path lengths
February 2003
SpecialTopics1b1c (English, PDF, 104 KB)
Aurora dx communication high in the north
February, 2003
SpecialTopics1b1a1b1a1a1 (BFLogotiny5, English, HTML, 104 KB)
Unusual Aurora QSO between DK3UZ and UA1ZCL
Dubus, 1, p 72, 2003
SpecialTopics1b1a1b1a (BFLogotiny8, English, HTML, 128 KB)
FAI on the edge, Southern England to Spain and Portugal
Dubus 1, p. 71, 2003
SpecialTopics1b1a2 (BFLogotiny11, English, PDF, 44 KB)
Evidence for 144 MHz transatlantic radio propagation?
January 2003, updated September 2003
SpecialTopics1b1d (English, HTML, 236 KB)
Transatlantische Funkverbindungen auf 144 MHz
UKW-Berichte, 4, 2002, p. 209-214
SpecialTopics1b3 (BFLogotiny9, German, PDF, 120 KB)
Ungewöhnliche Aurora-Funkverbindungen im 144 MHz Band
Dubus, 4, p. 39-41, 2002
SpecialTopics1b1a1b3 (BFLogotiny7, German, PDF, 260 KB)
Unusual Aurora observations in the 144 MHz band
"Off-normal Auroral scattering" in amateur radio
Dubus, 4, p. 35-39, 2002
SpecialTopics1b1a2a (BFLogotiny6, English, HTML, 340 KB)
Raising the treasure
Using dx cluster data in radio propagation studies
August, 2002
SpecialTopics1b1g (English, HTML, 56 KB)
DX Reichweite bei Aurora und FAI Funkverbindungen
Geographische Signatur von Rückstreuungen an erdmagnetfeldparalleln Irregularitäten
Dubus, 3, p. 31-32, 2002
SpecialTopics1b1a1b2a (BFLogotiny4b, German, PDF, 204 KB)
Dx radius in Aurora and FAI radio propagation
Geographical signature of backscattering aligned to the Earth's magnetic field
Summary paper
Dubus, 3, p. 23-30, 2002
SpecialTopics1b1a1b1b (BFLogotiny3a, English, PDF, 200 KB)
Dx radius in Aurora and FAI radio propagation
Geographical signature of backscattering aligned to the Earth's magnetic field
Part 2: North America
August, 2002
SpecialTopics1b1a1b4 (BFLogotiny2b, English, HTML, 564 KB)
Dx radius in Aurora and FAI radio propagation
Geographical signature of backscattering aligned to the Earth's magnetic field
Part 1: Europe
August, 2002
SpecialTopics1b1a2b (BFLogotiny1a, English, HTML, 1.1 MB)
50 MHz opening between Europe and North America
Multiple-hop propagation in the 6m band
Febuary 2002, July 2002 (revision)
SpecialTopics1b (BFLogotiny3, English, HTML, 128 KB)
Radio amateurs don't do it everywhere
November, 2001
SpecialTopics1b1a4 (English, HTML, 32 KB)
Hidden Mode of Sporadic-E?
More magic with the magic band
Part 2: Sea-/Land distribution in Europe
Febuary, 2000
SpecialTopics1b1a (English, HTML, 708 KB)
Hidden Mode of Sporadic-E?
More magic with the magic band
Webpage of the UK Six Meter Group, 1999
SpecialTopics1b1 (English, HTML, 520 KB)
Der Mond als passiver Reflektor,
Physikalische Grundlagen von EME-Funkverbindungen
October 1994, July 2002 (revision)
SpecialTopics1b4 (German, PDF, 140 KB)
Long-Delayed Radio Echoes: Observations and interpretations
VHF Communications, 2, p. 109-116, 1993
SpecialTopics1b1f (English, PDF, 972 KB)
Langverzögerte Radioechos, Beobachtungen und Deutungen
UKW-Berichte, 3, p. 163-169, 1992
SpecialTopics1b5 (German, PDF, 756 KB)
Incoherent Scatter: Principles and applications
VHF Communications, 1, p. 55-60, 1992
SpecialTopics1b1a2c1a (English, PDF, 572 KB)
Die Beobachtung des Mehrton-Effekts
UKW-Berichte, 3, p. 175-178, 1991
SpecialTopics1b2d (German, PDF, 320 KB)
Incoherent-Scatter: Grundlagen und Anwendungen
UKW-Berichte, 3, p. 170-174, 1991
SpecialTopics1b1a1b5a1 (German, PDF, 484 KB)
QTH-LOC: Funkstrecken am Computer
Dubus, 1, p. 37-39, 1990
SpecialTopics1a1 (German, PDF, 260 KB)
TV Amateur, 76, p. 1-2, 1990
SpecialTopics1b1a1a1 (German, PDF, 200 KB)
Beobachtungen über Rückstreuungen ultrakurzer Wellen an erdmagnetfeld-parallelen Irregularitäten innerhalb der E-Region in mittleren Breiten
Oktober 1989
SpecialTopics1b1a2c1 (German, PDF, 1.3 MB)
Zum Dopplereffekt bei Aurora-Verbindungen
Dubus, 3, p. 59-61, 1989
SpecialTopics1b1a1b (German, PDF, 196 KB)
Amadeus - Satelliten-Bahnverfolgung de Luxe
Beam, 5, p. 32-34, 1988
SpecialTopics1a1a (German, PDF, 604 KB
OLGA - Optimierung linearer Gruppenantennen
Dubus, 3, p. 212-217, 1988
SpecialTopics1a1a1 (German, PDF, 536 KB)
Ein einfaches Modell zur Identifizierung von Sporadisch-E
Dubus, 2, p. 128-132, 1988
SpecialTopics1b1b (German, PDF, 360 KB)
Is there an FAI-scatterer above Budapest?
Dubus, 2, p. 127-128, 1988
SpecialTopics1b1a2c (English, PDF, 176 KB, no figures
Aurora - A computer program to analyse Auroral- and FAI-scattering
Dubus, 2, p. 125-126, 1988
SpecialTopics1a1a1a (English, PDF, 196 KB)
Gibt es einen FAI-Scatterer über Budapest?
Dubus, 1, p. 21-23, 1988
SpecialTopics1b1a1b5 (English, PDF, 292 KB)
Aurora - Ein Computerprogramm zur Analyse von Aurora- und FAI Rückstreuungen
Dubus, 1, p. 18-21, 1988
SpecialTopics1a1a1a1 (German, PDF, 456 KB)
Long delayed echoes on EME-circuits
Dubus, 3, p. 244-245, 1987
SpecialTopics1b1a3 (English, PDF, 108 KB)
Entfernungsberechnung mit Grafik
Dubus, 3, p. 221-222, 1987
SpecialTopics1a1a1a1a (German, PDF, 176 KB)
Rückstreuungen ultrakurzer Wellen an Feldlinien-orientierten Irregularitäten
Dubus, 3, p. 182-189, 1987
SpecialTopics1b1a1b5a (German, PDF, 880 KB)
Gedanken zur Nutzung des 2m-Bandes
SpecialTopics1b1a1a1a (German, PDF, 504 KB)
Vorhersage der Schaueraktivität bei Meteor-Scatter-Verbindungen
Dubus, 2, p. 169-170, 1986
SpecialTopics1b2c (German, PDF, 140 KB)
a. Verschlechterung des Signal/Rauschverhältnisses durch Drehung der Polarisationsebene
b. Deterioration of signal/noise ratio by rotation of the polarisation plane
Dubus, 2, p. 155-156, 1986
SpecialTopics1b1e (German/English, PDF, 200 KB)
Der Mehrton-Effekt
Dubus, 1, p. 89-90, 1986
SpecialTopics1b1b1 (German, PDF, 220 KB)

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Unless otherwise stated, all material is copyright of Volker Grassmann. All rights reserved. The material, or parts thereof, may not be reproduced in any form without prior written permission of the author.

Legal notes (Impressum)