The GE TD714 (P/N 152-0402-00) is a 2.2 mA, 25 pF tunnel diode in a DO-17 package, used in the delay pickoff section of 547 SN 11490-UP.
NSN Cross ref part no is GE TD714. Also used in 546, 556 and 491.
152-0402-00 Tunnel Diode