What's Your Callsign?
As already mentioned, the radio operators and co-workers at Norddeich Radio had much humor, certainly more than outwardly appeared.  Sometimes our own colleagues were the victims of  of this humor.  This episode I saw in the mid 1970's as I sat in close proximity to the action.   
Two operators of Norddeich Radio had bought some superseded VHF equipment, had set it up at noon in a car in the parking lot at Norddeich Radio, and were eager to test it.  My colleague, Egon H. was working coastal radio telephony on 2182 kHz and UKW Channel 16 on 156.8 MHz, when suddenly a loud call on Channel 16 in English with a strange accent sounded.  " Norddeich Radio, Norddeich Radio I have a link call to Hamburg.  The number is 348987, I repeat the number is 348987.  My position is near Borkum Island .  I repeat, Borkum Island.  Do you read me?  Over."
The ship had now given all details, but not it's name or callsign, so Egon called back; " This is Nordeich Radio, what's your callsign?"  The answer was, "Yes, my callsign is ECHO GOLF OSCAR NOVEMBER." (Egon)  Egon H. reacted immediately and said, "OK my friend, in this case go to Hell."  We were shaking with laughter, and the "ship" never called again.