Yes this is correct. The resulting ciphertext from Enigma was sent by manual Morse transmission. Morse operators can identify others by thier “hand” which is the Morse equivalent of the sound of your voice in speech.

Earlier in the war the Germans typically sent their call signs in plaintext. Many of the intercept operators in the “Y stations” in the UK became familiar with the “hands” of various German operators. Later in the war the Germans started encrypting their call signs, but Bletchley was generally able to distinguish them by the intercept operator’s familiarity with the “hands” of the German Morse operators.