It means "from" and it probably comes from the French word "de". It was adopted by Morse Code operators because it is much faster to send "de" than "from".
At the close of a transmission, it means "this is."
In amateur radio, when someone asks what your QTH is, they are asking for your position, usually in latitude and longitude.
It means radio operations that are done as a hobby, or in the use of public service. Operators cannot (by law) earn money or material reward in any way, for the use of the radio. When we say Amateur radio/ Ham Radio these all sound same. There is very few authentic info about Amateur or HAM names, but i have read from very authentic version "radiosguide". They explain all the philosophy of amateur radio origin.
Deutscher Amateur-Radio-Club's motto is 'Federal Association for Amateur Radio in Germany'.
International Amateur Radio Union's motto is 'Representing the Interests of Two-Way Amateur Radio Communication'.
They are asking if there is any interference.
'K' is the prosign for 'over.'
Radio Amateur Association of Greece was created in 1958.
Bangladesh Amateur Radio League was created in 1979.
Japan Amateur Radio League was created in 1926.
International Amateur Radio Club was created in 1961.
Northwest Amateur Radio Society was created in 1985.
Deutscher Amateur-Radio-Club was created in 1950.