We are a small ham radio club from central Switzerland. We meet weekly for our regulars' table in a restaurant in the Lucerne area. Every year we participate in the Helvetia Contest and the CW and SSB Fieldday Contest.
By a lucky coincidence I discovered the QSL card of HB9JA in the catalogue of a big Swiss auction house.
It is the QSL card of HB9JA - Karl Hoppeler from Rüschlikon. He made a QSO with EA4HK from Madrid on 10 April 1949 at 21:00.
Unfortunately we do not know when and how long Karl Hoppeler used the callsign HB9JA.

QRP
QRP in amateur radio refers to operating at low power, usually less than 5 watts on short wave or 10 watts on ultra short wave. The aim is to cover long distances with as little power as possible, while maximising transmission efficiency.
QRP is particularly popular with radio amateurs who are interested in portable operation, building their own equipment and optimising their antenna systems.
The challenge and pleasure of making contact with other hams around the world using minimal power is what makes QRP so attractive.

Operating Modes
Low power modes in amateur radio, also known as QRP, include various communication modes that operate efficiently at reduced transmit power.
These include telegraphy (CW), SSB (single sideband) and digital modes such as PSK31 and FT8.
These modes allow effective connections to be made over long distances with minimal power, which is a particular challenge and promotes the technical skills of radio amateurs.

Self-assembly
In amateur radio, DIY refers to the independent design, construction and modification of radio equipment and antennas. Radio amateurs design and build their own equipment to improve their technical skills and test innovative solutions.
It promotes an understanding of electronics and radio technology, and allows for individual customisation and optimisation for personal needs.
Homebuilding is a creative and educational aspect of the hobby that also promotes the exchange of knowledge and experience within the amateur radio community.

CONTEST
An amateur radio contest is an organised competition in which radio amateurs try to make as many contacts as possible with other stations in a given period of time.
The aim is to collect points, which are awarded according to certain rules, for example based on the number of contacts, the distance to the stations, or the number of frequency bands used.
Contests promote technical expertise, understanding of radio conditions and the ability of participants to communicate effectively under difficult conditions.
We meet every week on Thursday evening at 20:00 in the Restaurant Chärnsmatt in Rothenburg.
We can be reached on the Lehn relay 438.400 MHz C4FM and/or FM (subaudio 71.9 Hz) or on the Pilatus relay 438.800 MHz (subaudio 71.9 Hz).