History of DL7AFB

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My life as Radio Amateur started in 1979 when I was 15 years of age. I joined the Radio Amateurs education centre at Radio Club Station DL0JR in Berlin Reinickendorf.  There I studied the fundamentals of Radio Frequency Design as well as Amateur Radio Law. In early 1980 I got my class C licence with callsign DD6DN. After that I did some CW Morse training at the Students Club Station of  Technical University Berlin, DK0TU,  and received my first class licence with callsign DL7AFB in winter 1980.

From the beginning my interest was the design of very high frequency and microwave equipment as well as the study of radio propagations like tropospheric scatter (tropo), aurora, sporadic-e (Es), meteor scatter (MS), moun bounce (EME) and amateur satellite communications (AMSAT OSCAR).

A very special interrelationship I'm having to my father, DL7AKL, who was not minor enthusiastics in homebrewing of Amateur Radio equipment. Together we realised scores of projects as linear high power amplifiers (HPA), low noise amplifiers (LNA) and antennas, respectively.

Some outstanding projects were the rebuilt of DK1OF's 2-m band Power Amplifier using one of EIMACS 4XC250B tetrodes, or the more exciting rebuilt of K2RIW's 70-cm Kilowatt Amplifier incorporating two 4CX250B in parallel. On the side some PAs were built with Telefunken's 2C39BA triodes for 432-MHz and 1,3-GHz, respectively.

On the weak signal side various types of preamplifiers were designed, tested and compared, matching the frequency range of 100 MHz  up to 10 GHz. Different purposes like lowest noise or high intermodulation free dynamic range had to be fulfilled. Types like BFT66, BF981, BFP193, MGF1402, 3SK97, CF300 or S3030 were investigated.

The best amplifier is always the antenna. This phrase keeps still valid. During the rebuilt of countless DL6WU Yagi Antennas we designed different types of element mounting techniques, e.g. insulating boom, conducting boom, insulated through metallic boom, etc. Antenna Measurement Parties were held in "Berliner Volkspark Rehberge".

At the end a quite powerful station grow up, being able to do some Earth-Moon-Earth (EME) contacts around the world.
Due to our poor radio location in the centre of Berlin City, more and more fielddays were carried out in the proximity of Berlin.

Since more than 25 Years the Amateur Radio Stations DL7AKL and DL7AFB carry on doing VHF-, UHF-, and SHF Contests.

Vy  73 es hpe cuagn

Bodo Woyde, DL7AFB

     last change 13.12.2006 23:18    Haftungsausschluß

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