Amateur Radio Propagation Studies


Science, research, engineering, operating


About DF5AI

Volker studied physics at the University of Göttingen, Germany. In 1983 he joined the Max-Planck-Institute for Aeronomie (which is now called the Max-Planck-Institute for Solar System Research) where he worked with the multinational EISCAT research group (European Incoherent Scatter Association). The focus of his research was thermospheric winds in the upper atmosphere, gravity waves, Aurora Borealis, sporadic E and the incoherent backscatter of radiowaves in the ionosphere. In mobile telecommunication he worked in operations, marketing and general management where he has designed and implemented a nationwide transmitter network and has introduced a number of innovative applications for consumers, authorities and security services. He currently works in the strategy department of one of Germany's largest companies. Although working in business, Volker still maintains his ties to science and research. He gave lectures at the Wiesbaden University of Applied Science and is very much interested in popular sciences which has finally motivated this web appearance.

Dr. Volker Grassmann, DF5AI

Amateur radio software

Volker developed a variety of amateur radio programs:

  • QTH_LOC is his first software using eye-catching screen maps
  • the Aurora program applies scientific results from the Max-Planck-Institute for Aeronomie to analyse Aurora and FAI radio propagation in real time
  • the prediction tool CHIRP ("Characteristics of ionospheric radio propagation") is based on the MINIFTZ routines courtesy of "Forschungsinstitut der Deutschen Bundespost am Fernmeldetechnischen Zentralamt"
  • AMADEUS ("Ausgewählte Methoden zur Auffassung und Darstellung elliptisch umlaufender Satelliten") is a satellite tracking program which, at its time of publication, outperformed other software products of this type because of its efficient calculation routines and its graphical capabilities
  • OLGA ("Optimierung linearer Gruppenantennen") is an antenna engineering tool which optimises the radiation pattern of stacked arrays
  • the latest update of the HamLogBook database cooperates with the BeamFinder software by sending actual QSO data to the program
  • its companion, the BeaconList database, files a large amount of beacon data and provides a variety of tools for hunting beacon signals
  • however, his biggest software project in amateur radio is BeamFinder which required thousands of hours in software development, testing, calculations and investigations. BeamFinder may be considered a living project due to the long list of functions, analyses and features which are planned for future releases

The BeamFinder software. Click image for more information on the software.

Pretty cold in Finland (-45 C = -49 F). Two EISCAT colleagues and Volker (in the middle) in front of the 32m dish.

Antenna design

Volker put his callsign on the air using many types of amateur radio antennas, including small arrays, e.g. the HB9CV, and structures such as Yagi arrays of 20, 40 and 80 elements, respectively. He has experimented with Helix-, Zigzag-, Log Periodic- and Short Backfire antennas, probably because radio amateurs are never satified with the current antenna system. In research, he worked with the big guns operated by the EISCAT organisation. Volker was on duty in Kiruna, Sweden, and in Sodanklyä, Finland, and since then he is fascinated by the Scandinavian culture, its hospitality and by the Scandinavian engineering skills. In mobile communication, Volker and his team built a nationwide transmitter network in Germany, comprising a large amount of basestations as well as satellite and terrestrial antenna systems.


EISCAT radar facility, Sodankylä, Finland

Digital photography

Since Volker got a digital single lens reflex camera, he views the world from a different perspective, i.e. with the eyes of a photographer. Friends are surprised about Volker's latest hobby but he says physics and, in particular, mathematical science has very much in common with art work: composing photographs is just another method of focusing on the beauties of this world. We all expect he will very soon enter the world of astrophotography too ...


Airplane crossing the lunar disk

Macro photography

Click on the locations to visit the lovely town of Idstein, JO40DF (DF5AI), and Carlingford, IO64WA (EI/DF5AI)


Volker is married to an Irish lady and he claims that their two daughters are real Irish characters too. Friends say this is an excuse because it is hard get the three femals to agree. He loves travelling to Ireland and you may find Volker and his family in the Irish pubs chatting away with the local residents.

If you can't find him there he's probably visiting the Newgrange monument which awakened his interest in archaeology ("we would fail if we try to place a couple of stones in our garden to predict astronomical events. However, the people from 5000 years ago made it").


The Newgrange monument, Co. Meath, Ireland, was build 5000 years ago



Legal notes (Impressum)

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.