DL1AO
Stefan Keller
Ham radio operator from Lower Bavaria
Hi, I'm Stefan
Stefan
DL1AO
From CB radio to Class A
It all started in the 90s with CB radio - callsign 13CT2162. The fascination with radio technology never left me, even though the path to an amateur radio license took a few decades.
My professional profile with background and contact info is at skeller.eu. Personal: Married, father, originally from the Baltic Sea coast. Since 2024 in Lower Bavaria - and feeling quite at home by now.
What is a callsign?
A callsign is the globally unique identifier of a radio amateur. It is assigned by the national telecommunications authority - in Germany by the Bundesnetzagentur (BNetzA). Each callsign is like a fingerprint: it reveals the country, region, and uniquely identifies the radio amateur.
Country Prefix
The first one or two letters indicate the country. Germany uses DA-DR: DN9 (Class N), DO, DA6 (Class E) and e.g. DL, DB, DK, DM (Class A). The US uses W, K, N and A - Japan uses JA among others.
Numeral
The digit after the prefix is part of the callsign. In some countries it has regional significance, in Germany it is part of the allocation and no longer a geographic district code.
Suffix
For personal German amateur radio callsigns, two- or three-letter suffixes are typically assigned.
Not just anyone on the air
Amateur radio is one of the few hobbies that requires a government exam. For good reason: radio amateurs transmit with up to 750 watts on their own frequency bands. A poorly tuned transmitter generates harmonics - multiples of the transmit frequency that can fall into other bands and interfere with broadcasting, wind profiling radars, or other radio services. On some bands, amateur radio only has secondary status and must not interfere with other services.
Technology
Electrical engineering, circuit design, wave propagation, antenna technology, measurement techniques and EMC. The exam is tiered: Class N covers basics, Class E goes deeper, Class A requires comprehensive understanding.
Regulations
Amateur radio law, regulations, international rules (ITU), operating procedures and frequency allocations. You need to know what you can do - and what you can't.
Operating Practice
The Q-code system, NATO phonetic alphabet, logbook keeping, contest operating, and proper on-air conduct. Radio discipline is not optional.
Three license classes in Germany
- Class N (Entry-Class) - new since June 2024. 3 bands (10m, 2m, 70cm), max. 10 W ERP on 10 m, 6.1 W ERP on 2 m and 70 cm. Callsigns with prefix DN9. Valid in Germany only - a quick start for trying out.
- Class E (Novice-Class) - additional HF bands (e.g. 160m, 80m, 15m) and VHF from 2m, max. 100 Watt PEP. Callsigns with prefix DO1-DO9 or DA6. Internationally recognized under ECC/REC/(05)06 (CEPT Novice License) - e.g. in Austria, Switzerland, Netherlands, UK and more.
- Class A (Expert-Class) - all amateur radio bands, max. 750 Watt PEP. Callsigns with prefix DA1-2, DB, DC, DD, DF, DG, DH, DJ, DK, DL or DM. HAREC recognition under CEPT Recommendation T/R 61-01 - valid in numerous countries including all of Europe, USA, Canada, Australia and Japan.
- The exam is administered by the Bundesnetzagentur. All classes can be taken on the same exam day - if you don't pass Class A, you automatically receive the E license, provided those parts were passed.
- Preparation: Self-study, online courses like 12db.de or courses at local DARC chapters.
History of Amateur Radio
The Beginnings
Around the turn of the century, hobbyists and tinkerers in the US and Europe were already experimenting with homemade radio transmitters. The term "amateur" doesn't mean "beginner" - it means someone who operates out of passion, not commercially. The first radio amateurs were pioneers of wireless communication.
ARRL Founded
Hiram Percy Maxim founds the American Radio Relay League (ARRL), the oldest and still largest amateur radio organization in the world. The idea: relay messages by radio from station to station over long distances.
Transatlantic on Shortwave
In 1921, amateur radio signals are received across the Atlantic for the first time (one-way). In 1923, the first two-way transatlantic shortwave contact follows. Experts had claimed it was impossible. The amateurs proved them wrong - laying the foundation for worldwide shortwave communication.
IARU Founded
The International Amateur Radio Union (IARU) is founded in Paris. It represents the interests of radio amateurs worldwide at the ITU and coordinates international cooperation.
Organized Amateur Radio in Germany
The Deutsche Amateur-Sende- und Empfangsdienst (DASD) is founded in Kassel - the predecessor of today's DARC. After the war, the Deutscher Amateur-Radio-Club (DARC) is established in 1950 in Bad Homburg, today with about 33,000 members the largest amateur radio association in Europe.
The Brick Protest and the Amateur Radio Law
When the legislative process stalls, German radio amateurs launch a legendary protest: on January 15, 1949, they send masses of bricks to the Economic Council - "to underpin the amateur radio law." The postal service has to deploy extra trucks. It works: the Amateur Radio Law is passed on March 14, 1949 - before the German constitution.
OSCAR 1 - Amateurs in Space
OSCAR 1 (Orbiting Satellites Carrying Amateur Radio) is launched - the first amateur radio satellite in history. Radio amateurs become one of the first non-governmental groups to operate their own satellites in orbit.
Packet Radio - Data Before the Internet
Canadian radio amateurs led by Robert Rouleau (VE2PY) begin digital data transmission by radio. In the following years, bulletin boards and networks emerge - long before the internet becomes widely accessible, radio amateurs connect digitally.
Modern Amateur Radio
FT8, moonbounce (EME), Software Defined Radio, digital modes, and satellite communication. Amateur radio is more alive than ever - a blend of tradition and high-tech that connects approximately 3 million license holders worldwide.
Notable Callsigns
Amateur radio connects people from all walks of life - including some you might not expect.
One of the most famous radio amateurs in the world. Regularly active on the bands and known for his friendliness during QSOs.
The former King of Spain is a licensed radio amateur and was regularly heard on the HF bands. The special prefix EA0 was reserved for the royal family.
The German Chancellor is a licensed radio amateur. He follows a tradition of prominent politicians with amateur radio licenses - including US Senator Barry Goldwater (K7UGA).
Legendary author of countless amateur radio technical books. His "Radio Handbook" was the standard reference for radio amateurs worldwide for decades and inspired generations of homebrewers.
The legendary Hollywood actor ("The Godfather") was a licensed radio amateur (also under KE6PZH in the US). His callsign FO5GJ stands for French Polynesia.
The German callsign in Antarctica. When licensed radio amateurs are present at the research station, radio contacts from the end of the world are possible - a highlight for anyone who receives a QSL card from there.