View 2n6027 datasheet:

MOTOROLA Order this document SEMICONDUCTOR TECHNICAL DATA by 2N6027/D 2N6027 Programmable 2N6028 Unijunction Transistors Silicon Programmable Unijunction Transistors . . . designed to enable the engineer to “program” unijunction characteristics such as PUTs RBB, ?, IV, and IP by merely selecting two resistor values. Application includes 40 VOLTS thyristor-trigger, oscillator, pulse and timing circuits. These devices may also be used 300 mW in special thyristor applications due to the availability of an anode gate. Supplied in an inexpensive TO-92 plastic package for high-volume requirements, this package is readily adaptable for use in automatic insertion equipment. • Programmable — RBB, ?, IV and IP. • Low On-State Voltage — 1.5 Volts Maximum @ IF = 50 mA G • Low Gate