In the summer of 1924 Ernst Krenkel went to Leningrad with what little money he had saved, hoping to find employment as the radio operator on any ship undertaking a long voyage. At that time, only specially designated Soviet vessels went on long voyages, and in Leningrad there were already qualified naval radio operators without work. Just when Krenkel had given up all hope of finding work he was told that the hydrographic management bureau was in urgent need of a radio operator prepared to go on any expedition, to any island in the Arctic ocean. There was little interest because the pay was poor and it was necessary to be away for the whole year, living in ‘hellish’ conditions.
Ernst rushed around for an interview, and was offered a post. With a small advance on his salary, and 
wearing his new naval uniform he set off by train to Arkhangelsk (Archangel). On arrival he was assigned to the “ Yugorski Shar “ which was preparing to take the relief crew to the first Soviet polar observatory “Matochkin Shar”, constructed the year before on the northern coast of the Matochkin Shar strait of the Novaya Zemlya archipelago.
After returning to Moscow the following year he was enlisted in the Red Army and served in the radiotelegraphic battalion in Vladimir. At around this time the USSR government decided to allow ‘private radio stations’ on the short-waves. 
Ham radio was born in the USSR and Ernst Krenkel was delighted. Soon he was on-air using homebrew equipment, with the callsign EU2EQ (later U3AA).
This is just a brief anticipation of what is well reported in the detailed article available with lots of historic pictures which tell of the heroic deeds of Ernst Krenkel RAEM.
Read the whole history at: https://qst.su/archives/29525
But Ernst Krenkel traveled also to Antarctica and operated under the call RAEM/MM in 1968/1969. Thanks to Oleg UA6GG for providing WAP few historical QSLs shown above, which confirm Krenkel’s radio operations activity in Antarctica
TNX Oleg UA6GG
www.dxtrophy.com