Yeah, oldest electronic, or oldest thing? I have a set of fireproof bankers drawers with a functioning rotary lock from like 1917. Oldest electronic... Do speakers count? I have a set of Acoustalinear speakers hooked up to a sound system... Or my grandpa's old neon sign from the 1950s (although it has some newer parts... Ballasts and what not do not last for ever). I also have some old electric tube transistors in an old radio I restored that have "made in West Germany" stamped on them... But those might be from the 90s... I am not sure.