 On 6 June 1941, Schumacher was drafted in to the German army and Shulze-Boysen found a replacement radio operator in Hans Coppi.Schulze-Boysen persuaded Coppi to take on the task of establishing a radio link to the Soviet Union for the resistance organization.Both Harnack and Coppi were trained by a contact of Korotkov, in how encipher text and how to transmit it, but Coppi failed to send any messages, due to inexperience and technical problems with the radio.