Symbol 5076-1973 from IEC 60417 - Title/Meaning: Earphone Function/description: To identify the socket, terminals or switch for an earphone.
Additional information: 
Published in: First edition, 1973
Own work using: iso.org/obp/graphics/grs/70de7c8f-72cc-40ae-a1d6-445bcf7a4c79 200.png
Vectorization:  Mrmw